Poster Abstracts

Posters will be presented on Monday, July 9 between 1730-1930 during the Wine & Cheese Reception.

 

P901 Higher level of neuroendocrine differentiation and aggressive clinical behavior in basaloid predominant squamous cell carcinomas of the lung

Kianoosh Keyhaniana, Chi Laia, Marcio Gomesa, Brian Loa, Harman S. Sekhona, .

aDepartment of Pathology and Laboratory Medicine, University of Ottawa/The Ottawa Hospital, Ottawa, ON.

Background/Objective: Basaloid Squamous Cell Carcinoma (B-SqCC) is an uncommon entity that exhibits histological overlaps with small cell carcinoma (SCLC) including neuroendocrine differentiation (NE-d). Our objective was to assess the NE-d in B-SqCC and its prognostic impact comparing with poorly-differentiated SqCCs (PD-SqCC).

Methods: Patients: 40 B-SqCC, 9 peripheral SCLC, 21 PD-SqCCs; institutional resections 2005-2016. After review of 40 B-SqCCs by two thoracic pathologists, 20 cases were identified as basaloid predominant (BP)-SqCC (10 pure basaloid and 10 with >50% basaloid differentiation). Two blocks per case were used for immunohistochemical stains.

Results: NE-d was identified in 65% (13/20) of BP-SqCCs, demonstrated by >10% cell positivity with one NE marker while 40% (8/20) demonstrated >one NE marker positivity. In comparison, only 19% of PD-SqCCs (4/21) showed >10% cell positivity with one NE marker (p<0.01) and none showed >one NE marker positivity. Interestingly, 30% of pure B-SqCC tumors showed >10% TTF1 positivity.

Clinically, 50% (5/10) of pure B-SqCC cases presented with stage T3 or higher compared to 14% (3/21) of PD-SqCC (p=0.02). Moreover, 50% (10/20) of BP-SqCCs experienced <2 years disease-free survival (DFS) compared to 23% (4/17) of PD-SqCC (p=0.031). A lower 2-year DFS trend was seen in BP-SqCCs with NE-d compared to BP-SqCCs without NE-d (54% (7/13) vs. 43% (3/7), respectively).

Conclusions: Our study demonstrates that NE-d in B-SqCC tumors can pose a diagnostic challenge especially in biopsy specimens. Although currently managed similar to SqCC, B-SqCCs exhibit higher NE-d, present at higher T-stage and have shorter DFS. Therefore, further molecular and management studies are required.

Keywords: : basaloid squamous cell carcinoma, neuroendocrine differentiation, small cell carcinoma

Back To Top

 

P902 Fatal ketoacidosis as the first presentation of multiple sclerosis

Marta Kisiela, Linda Kocovskia,b.

aDepartment of Pathology and Molecular Medicine, McMaster University, Hamilton, ON.
bHamilton Regional Forensic Pathology Unit, Hamilton, ON.

Ketoacidosis may lead to mortality through electrolyte disturbances and volume contraction causing cerebral edema and sudden cardiac arrest. Starvation rarely causes significant metabolic acidosis in healthy individuals as sufficient insulin is produced to mobilize glycogen stores. However, starvation may lead to significant metabolic derangements in cases of physiologic stress or high glucose requirements.

In this case report, we describe the unexpected death of a 60-year-old woman who reported symptoms of weakness, headache and increasing thirst in the weeks preceding her death. Vitreous fluid analysis showed the presence of ketones without an associated elevation of glucose. In addition, characteristic Armanni-Ebstein lesions were present in the kidneys. There was no microscopic evidence of diabetic nephropathy and hemoglobin A1c (HbA1c) level was within a non-diabetic range. The findings were in keeping with non-diabetic ketoacidosis as the cause of death.

Interestingly, the clinical context for the non-diabetic ketoacidosis was likely inadvertent fasting secondary to multiple sclerosis, first diagnosed at autopsy. Multiple sclerosis (MS) is a demyelinating disease of the central nervous system with a heterogenous course that can cause significant disability and mortality. Clinical symptoms of MS are variable and previous symptoms may have been attributed to other causes by the patient.

The individual’s undiagnosed MS would have generated the physiologic stress to produce fatal results after fasting was initiated. This highlights the importance of considering autopsy findings that may initially appear unrelated in the context of the clinical information available to determine if they provide unified evidence for the cause of death.

Keywords: Non-diabetic ketoacidosis, Armanni-Ebstein lesion, multiple sclerosis, forensic pathology

Back To Top

 

P903 Ovarian microsystic stromal tumour – a potential pitfall on intraoperative consultation

Yaogong Lia, Omar Al-Nourhjib, Mary Kinlochb.

aGeneral Pathology Resident, PGY1, Department of Pathology and Laboratory Medicine, University of Saskatchewan, Saskatoon, SK.
bDivision of Anatomic Pathology, Department of Pathology and Laboratory Medicine, University of Saskatchewan, Saskatoon, SK.
Correspondence: Mary Kinloch MD FRCPC, Mary.kinloch@saskhealthauthority.ca.

Introduction: Ovarian microcystic stromal tumour (MST) is a rare stromal tumour and recently introduced into the “WHO Classification of Tumours of Female Reproductive Organs” (2014). Given its’ rarity, recognition remains challenging. Here we present a case of MST, diagnosed as benign tissue on intraoperative consultation (IOC).

Clinical Presentation: The patient, 44-year-old female, presented with abdominal pain. Computed tomography imaging showed a large left adnexal cystic structure with complex wall thickening.

Results: At IOC, portion of the MST was interpreted as residual, unremarkable ovary separate from the adjacent benign cyst indicated for surgery. On permanent sections, the histology shows fibrous bands sub-dividing the tumor into cellular islands with characteristic microcystic pattern. The tumor cells have bland histomorphology with round nuclei, absent nucleoli and low mitotic score. Vimentin, CD10, WT-1 and beta catenin (nuclear staining) are all positive, characteristic for MST, given its’ mutations in the WNT pathway.

– click here for figure

Conclusion: Since MST’s introduction, around 20 cases have been reported. We present first case in practice to highlight the challenge to identify the tumour at IOC, which the disagreement from a benign ovarian cyst to a benign MST may seem minor, but the clinical implications could be significant.

Keywords: Microcystic stromal tumour(MST); Intraoperative consultation(IOC); Ovarian cyst; WNT pathway

Back To Top

 

P904 The Use of Tandem Mass Spectrometry in Screening and Confirmation Testing of Drugs of Abuse

Bassam A. Nassar, Lisandra Cubero Herrera, Amy H. Lou, Marc P. Goguen.

Department of Pathology and Laboratory Medicine, Nova Scotia Health Authority Central Zone and Dalhousie University, Halifax, Nova Scotia.

Objective: Forensic urine testing for drugs of abuse (DoA) requires definitive confirmation. Earlier SAMHSA Guidelines advocated screening by immunoassay (presumptive) and confirmation by gas chromatography-mass spectrometry (GC-MS) (definitive), or thin layer chromatography (TLC) for benzodiazepines. Newer alternative technologies are now desirable due to cost, labour and turn-around time benefits. We hence opted for liquid chromatography-tandem mass spectrometry (LC-MS/MS) for targeted screening and confirmation of 31 DoA and metabolites.

Methods: Testing for benzodiazepines, benzoylecgonine, methadone, opioids/opiates, amphetamines, methylphenidate/ritalinic acid, and phencyclidine was performed on two separate dedicated (screening or confirmation) 3200 QTRAP LC-MS/MSs. Samples were tested following forensic toxicology guidelines. During screening, samples were mixed with internal standards and incubated with β-Glucuronidase. After protein precipitation, supernatants were injected on the LC-MS/MS. Drugs were identified by retention times (RT) and one multiple reaction monitoring (MRM) transition. Samples at or above cutoffs were re-extracted and analyzed by LC-MS/MS using RT and one MRM ratio for confirmation.

Results: Screening and confirmation by LC-MS/MS allowed accurate quantitation of 31 drugs and metabolites. For opioids and opiates, 10 analytes were identified in each run. This also applied to 11 benzodiazepines and metabolites, an advantage not previously available by TLC; while methadone/EDDP testing provided regular monitoring for the Methadone Treatment Program.

Conclusions: Forensic DoA testing in two separate definitive steps by LC-MS/MS provides quantitative information that eliminates the presumptive testing provided by immunoassay and avoids false positive results. Additionally, it improves turn-around times compared to GC-MS, and apart from upfront equipment cost, is a cost effective approach.

Keywords: Forensic Urine Drug Screen, Screening, Confirmation, Liquid Chromatography-Mass Spectrometry/ Mass Spectrometry

Back To Top

 

P905 Infectious Etiologies Potentially Under-Recognized in Granulomatous Testicular Disease

Taylor Bronson, Jenny Ross, Anjana Yeldandi, Ximing Yang.

Objective: Granulomatous orchitis (GO) is an uncommon disease process that has severe consequences for male fertility in young patients if not recognized and treated properly. Several etiologies for granulomatous orchitis exist and diagnosis is often difficult requiring extensive workup by the pathologist. Many cases are signed-out as “nonspecific/idiopathic GO” may lead to lacking specific treatment and possibly significant morbidity for the patient. We reviewed cases of GO at our institution to further characterize this difficult entity.

Methods: We searched our surgical pathology database of the prior 8 years for (granulomatous lesions in the testis. We identified 9 unilateral orchiectomy specimens fitting criteria for our study. Histology, previous immunohistochemistry (IHC) and special stains (SS) performed were reviewed for all cases. Additionally for each case, IHC for Toxoplasma gondii, Treponema pallidum, and AFB and GMS SS were performed on two blocks not previously subjected to prior ancillary testing.

Data and Results: Median age of patients was 54 years (ranging 21-68). 3/9 cases presented as an enlarged testis/mass, and 1/9 with testicular pain. 2/9 had positive toxoplasmosis serology. 1/9 had a positive urine culture for AFB. Follow-up data was available for 6/9 patients. There was no documented loss of a contralateral testicle.

Additional ancillary testing performed showed previously unseen acid-fast organisms in 1/9 cases. For full IHC and SS results, please see Table 1.

Table 1. Results of additional histochemistry and immunohistochemistry performed on previously untested blocks.

Patient Age

Age

T. gondii IHC

T. pallidum IHC

AFB SS

GMS SS

1

+

+

2

+

3

4

5

6

7

8

9

Conclusions: Granulomatous orchitis remains an entity which is difficult to identify etiology. In 3 of 9 cases we were able to identify defined causative organisms including toxoplasma and AFB. We propose the use of a combination of detailed clinical history, serological and microbiology tests as well as thorough pathologic evaluation for each case of granulomatous orchitis, which may reveal a treatable etiology for this disease.

Back To Top

 

P906 Pitfalls in the diagnosis of gastrointestinal stromal tumors

Moodley, Jinesa1, Tayyari, Farnoosh2, Koutsogiannis, Dimitri3, Cutz, Jean-Claude2, Schell, Miranda1.

1Department of Pathology and Molecular Medicine, McMaster University Medical Centre.
2Department of Pathology and Molecular Medicine, St-Joseph’s Healthcare Hamilton.
3Niagara Health System.

Objective: This case series highlights important mimics of Gastrointestinal Stromal Tumors (GIST), in order to avoid incorrect diagnosis and inappropriate treatment of gastrointestinal mesenchymal lesions.

Methods: Three cases were selected for which GIST was a major diagnostic consideration, whereby an alternate diagnosis was given after review.

Results: A 65 year-old female with a biopsy-proven gastric GIST, treated with neo-adjuvant imatinib and wedge resection of stomach, presented three years later with a new perigastric lesion. Microscopic examination showed a nodular, moderately cellular spindle cell lesion initially favoured to be recurrent/metastatic GIST; detailed comparison of the initial and subsequent specimens, including immunohistochemistry, supported the diagnosis of a reactive nodular fibrous pseudotumor.

A 55 year-old male underwent a resection of a paraesophageal mass. Microscopic examination showed a fascicular arrangement of bland spindle cells with a second population of dendritic-like cells. Immunohistochemical staining with CKIT, DOG1, Caldesmon and Desmin raised the possibility of GIST; the final diagnosis was an esophageal leiomyoma with hyperplasia of interstitial cells of Cajal.

A 65 year-old male presented with intra-abdominal hemorrhage from a sigmoid mesentery lesion. Microscopic examination showed malignant spindled and epithelioid cells arranged in solid sheets with foci of anastomosing, poorly-formed vascular channels. Immunohistochemistry showed positive staining for CD34 and CKIT, raising the possibility of GIST; additional staining with vascular marker ERG confirmed the diagnosis of angiosarcoma.

Conclusions: While GIST remains the most common gastrointestinal mesenchymal lesion, awareness of morphologic and immunohistochemical mimics is essential in correctly diagnosing these lesions in order to avoid over or under-treatment.

Keywords: Gastrointestinal Stromal Tumor, GIST, Mimics, Pitfalls

Back To Top

 

P907 Endometrial stromal tumour with sex cord like elements, pitfall for carcinosarcoma: a case report with a new insight into pathogenesis

Elizabeth O. Ferreiraa, Emma Markstromb, Marc Duprea,c,d, Francis Shiha,c,d, Sarah Keanb, Cyrille Bicamumpakaa,d,e.

aDepartment of Anatomical Pathology, University of Manitoba, Winnipeg, Manitoba.
bDepartment of Obstetrics and Gynecology, University of Manitoba, Winnipeg, Manitoba.
cDepartment of Pathology, St. Boniface Hospital, Winnipeg, Manitoba.
dDiagnostic Services Manitoba, Winnipeg, Manitoba.
eDepartment of Pathology, Health Sciences Centre, Winnipeg, Manitoba.

Introduction: Compared to the UTROSCT (uterine tumour resembling ovarian sex cord tumour), which normally exhibits >50% sex cord elements and a relatively benign course, ESTSCLEs (endometrial stromal tumour with sex cord like elements) are traditionally defined as <50% sex cord elements and are associated with worse outcomes. As a result, separate mechanisms of pathogenesis have been posited for these two tumour types. We present a case of an ESTSCLE exhibiting a PHF1 unbalanced rearrangement that phenotypically more closely resembles a poorly behaving UTROSCT.

Clinical Presentation: 60y old female who presented with postmenopausal bleeding and a rapidly enlarging pelvic mass. Endometrial biopsy pathology reported uterine carcinosarcoma. She underwent a laparoscopic hysterectomy, bilateral salpingo-oophorectomy, omentectomy, washings, bilateral pelvic and para-aortic lymph node dissection.

Results: The patient was found to ultimately have an ESTSCLE exhibiting 3’PHF1 probe loss on surgical excision. The tumour exhibited polyphenotypic IHC staining, with positivity for smooth muscle (desmin), epithelial (AE1/AE3), and sex cord markers (CD56, calretinin) similar to carcinosarcoma. Morphologic characteristics include deep myometrial invasion, lymphovascular invasion and necrosis. Interestingly, our case exhibits >50% sex cord elements, which has not been previously reported in ESTSCLEs.

Conclusion: This case challenges the definitions of ESTSCLE and UTROSCT as it exhibits phenotypic features of both (i.e. sex cord distribution and IHC profile of UTROSCT, morphologic and molecular features of ESTSCLE). As a result, we argue that the UTROSCT and ESTSCLE spectrum of pathogenesis may be more similar than previously thought. Furthermore, these polyphenotypic features on biopsy may be confused with carcinosarcoma.

Keywords: endometrial stromal tumour with sex cord like elements, uterine tumour resembling ovarian sex cord tumour, pathogenesis, carcinosarcoma

Back To Top

 

P908 Abdominal Pregnancy Resulting in a Fully Developed Fetus – The Importance of Thorough Microscopic Examination

Loganathan Ka, Baker Pa, Stefanovici Ca.

aDepartment of Pathology, University of Manitoba, Winnipeg, MB.

Introduction: Abdominal pregnancy is a rare variant of ectopic pregnancy accounting for 1.4% of all ectopic pregnancies (1 in 10,000 pregnancies). Due to its rarity and intricate anatomic changes, misdiagnosis on clinical and imaging studies may occur. Very few cases in the literature present the pathological findings of such an event.

Clinical Presentation: We report the case of a 29 years-old primigravida who presented initially with low-blood pressure and abdominal pain. She was diagnosed by imaging studies with a bicornuate uterus and followed closely. At 33 weeks, due to olygohydramnios, she was given steroids to minimize fetal prematurity-problems, and a C-section was performed. Intraoperatively a fully-developed extrauterine fetus and abdominally implanted placenta were identified and extracted. A hysterectomy was required due to catastrophic hemorrhage. All tissue was submitted for pathological assessment.

Results: Gross and microscopic examination of the sent tissue showed a circumferential thick layer of organized hemorrhage, interpreted on imaging as “bicornuate uterine wall”. There was hemorrhagic infarction with migration and adherence, but not true implantation, of the placental villi to omentum, cul-de-sac, sigmoid colon, etc, demonstrated by the lack of intermediate trophoblast and vascular recruitment in those areas. The main implantation site however was the left adnexa, establishing the diagnosis of a ruptured tubal pregnancy with expulsion of a viable fetus and secondary development in the abdominal cavity.

Conclusions: Pathological examination of the placental tissue clearly demonstrates that in an abdominal pregnancy, placenta can adhere superficially to other organs, but without true implantation resulting in a viable fetus.

Keywords: Ectopic, intraabdominal pregnancy, placenta

Back To Top

 

P909 Late recurrence of cervical cancer, retrospective study from a single cancer institute

Elmaghraby, Nermine1, Nirmalanantham, P.1, Sur, M.4, Schnarr, K.2, Elit, L.3, Aziz, T.4, Kazerouni, H.4, Wright, J.2, Lytwyn, A4.

1Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON.
2Department of Radiation Oncology, Juravinski Cancer Centre, Hamilton, ON.
3Department of Obstetrics and Gynecology, Juravinski Cancer Centre, Hamilton, ON.
4Department of Pathology and Molecular Medicine, Juravinski Hospital, Hamilton, ON.

Background: Women with cervical cancer have 8-25% recurrence risk, and 89%-99% recurrences present within 5 years of the primary cancer. Literature is limited on late recurrences 5 years after the primary cancer.

Objectives: Describe clinical, radiologic, pathologic characteristics of late recurrent cervical cancer.

Methodology: This is a retrospective study at a single cancer institute. The computerized pathology database was searched from years 1995 to 2011, cases then hand-searched for late recurrences. Clinical, radiology and pathology reports were reviewed.

Results: We identified 32 patients with recurrent cervical canc er; of these 7 presented 7-36 years after treatment. Four were squamous (SCC) and 3 adenocarcinomas. Six were stage IB or higher; one was IA with lymphovascular invasion. Recurrences occurred in vaginal vault, vesicovaginal fistula, bladder neck, cervix, femur, ovary, iliac and para-aortic lymph nodes. Ancillary testing to exclude a second primary and confirm cervical origin was used in 3 patients whose primary cervical cancers had occurred 8,13, and 19 years earlier: oncogenic human papillomavirus tissue testing was positive in 2 cases, and in the third case p16 was positive together with negative immunohistochemistry specific for other sites.

Conclusion: Late cervical cancer recurrence is uncommon and a second primary may need to be considered. Pathology work up will depend on the clinical, imaging and morphological context. Testing for p16 and HPV may be useful.

Back To Top

 

P911 Frozen section education in an anatomical pathology residency program

Robyn Ndikumana, Simon Kirby.

Department of Anatomical Pathology, Memorial University, St. John’s, NL.

Frozen section consultations are important for pathologists, allowing collaboration with surgeons to examine tissue, formulate a diagnosis, and help direct a surgical procedure. Frozen sections remain challenging for many reasons, including the high stakes nature of the experience, irreversible implications of an error, risk of sampling error, artifacts, limited slide quality, and lack of available special studies, among others. Despite these challenges, not all residency programs incorporate formal teaching of frozen sections in their curriculum, and scant literature exists regarding residency training in frozen sections.

Objectives: To determine if a frozen section education pilot project is beneficial to an Anatomical Pathology Residency training program, and to explore gaps in medical education surrounding the topic of frozen section education in an Anatomical Pathology training program.

Methods: A pilot study of ten teaching sessions among eight anatomical pathology residents at Memorial University was conducted, where two archived frozen section cases were presented at each session. Participants were given a clinical history and were asked to describe the microscopic findings of the touch preparation, frozen section, and ultimately the permanent section, with emphasis on how they would communicate their findings to the surgeon. Following the final teaching session, participants completed a survey to evaluate the value of the teaching sessions.

Results: Our study demonstrated that participants felt that they benefited from these sessions and would like to see an emphasis on frozen sections in residency programs, on a regular basis, and beginning exposure to frozen sections early in residency training.

Keywords: Frozen section, resident, education, anatomical pathology

Back To Top

 

P912 Female Genital Schistosomiasis in a Canadian Traveller

Jake A. Yorke, Saul L. Offman.

Department of Pathology, Dalhousie University, Halifax, Nova Scotia.

Introduction: Female Genital Schistosomiasis (FGS) is the disease associated with Schistosoma eggs in the upper or lower female genital tract, primarily affecting women in endemic areas. Typical symptoms include infertility or abnormal uterine bleeding. Rarely, the disease is primarily vaginal. Herein we present a case of vaginal FGS developing in a Canadian traveller.

Clinical Presentation: A woman in her 20s developed multiple firm papules and localized pruritus on the vaginal wall, weeks following return from travel. This included swimming in a river in a region endemic for Schistosomiasis. Examination revealed an otherwise well woman with vaginal mucosal erythema.

Results: The biopsy specimen revealed necrotizing granulomatous inflammation with Schistosoma eggs. Serology was positive for Schistosomiasis EIA.

Conclusion: This case of primary vaginal FGS serves to highlight the importance of considering this rare entity in patients with a travel history, including those with an atypical presentation.

Back To Top

 

P913 Combination of cyclin-D1 and MCM2 immunohistochemistry can reliably distinguish uterine leiomyosarcomas

Kianoosh Keyhaniana, Janice Lagea, Elizaveta Chernetsovaa, Zohreh Eslamia, Shahid Islama.

aDepartment of Pathology and Laboratory Medicine, University of Ottawa/The Ottawa Hospital, Ottawa, ON.

Objective: Our objective was to evaluate the diagnostic utility of two new proliferation markers, cyclin-D1 and minichromosome maintenance complex component-2 (MCM2), in differentiating the spectrum of smooth muscle tumors (SMTs).

Methods: Total number of cases: 45. An institutional database search (2009-2017) identified 10 cases of uterine leiomyoma with bizarre nuclei (LBN), 12 SMTs of uncertain malignant potential (STUMP), 13 leiomyosarcomas (LMS) and 10 recent leiomyomas as controls. Immunohistochemistry was performed on one block from each lesion and the hotspot nuclear positivity was recorded.

Results: Cyclin-D1 positivity in LMs, LBNs and STUMPs ranged from <1-80% of neoplastic cells. In these lesions, 41% (13/32) of cases had <5% positivity for cyclin-D1, whereas 31% (10/32) demonstrated >50% positivity. Interestingly, 92% (12/13) of LMSs showed <5% nuclear reactivity for cyclin-D1.

The ratio of MCM2 positivity exhibited a similar wide range (<1%- 90%) in LMs, LBNs and STUMPs, with 9% (3/32) of cases having <5% positivity and 12% (4/32) with at least 80% positivity. Remarkably, 92% (12/13) of LMSs were diffusely and strongly positive for MCM2 (>90% positivity). Importantly, a combination of low (<5%) cyclin-D1 and diffuse (>90%) MCM2 positivity demonstrated 97% specificity for LMSs in our cohort. Addition of Ki67 (<5%) to the model, improved the specificity to 100%.

Conclusion: Herewith, we describe the immunohistochemical profile of two new proliferation markers, cyclin-D1 and MCM2 in uterine SMTs. A combination of low cyclin-D1 expression together with strong and diffuse MCM2 positivity and high Ki67 index can reliably distinguish LMSs from more benign histological mimics.

Keywords: smooth muscle tumor, cyclin-D1, MCM2, leiomyosarcoma

Back To Top

 

P914 The Lumpy Journey of Diagnosing Lung Metastasis of a CNS Primary solitary Fibrous Tumor – A Case Report

Qi Yanga, Vivian(Miao) Lua,b, Marc Del Bingioa,b, Gefei Qinga,b.

aDepartment of Pathology, University of Manitoba, Winnipeg, MB.
bShared Health Manitoba, Winnipeg, MB.

Introduction: Solitary fibrous tumor is a rare mesenchymal tumor which generally considered as a benign entity. Because of the diagnosis is often exclusive and challenging, supportive clinical presentation and history are often needed. We are here to present a case of mislabelled CNS solitary fibrous tumor with multiple lung metastases, and share the difficulties we encountered and lessons we learned during the diagnosing process.

Clinical Presentation: A 60-year-old male with 18-year history of CNS PNET present with multiple lung nodules. CT guided lung biopsy was done for pathology diagnosis.

Results: The H&E morphology of lung biopsy is similar to previous CNS PNET showing mild atypical cohesive cells with round to oval nucleus without spindle morphology, which is not typical for SFT.

Immunohistochemistry stains of positive CD99 and false positive NSE lead to the diagnosis of CNS PNET 18 years ago. Current stains are positive for CD34, Bcl2, CD99, Factor13A, Beta catenin, STAT-6, with STAT-6 being a much more reliable marker compare with those in year of 2000; negative of Synaptophysin, NSE, EMA, GFAP, NeuN, PAX5, cytokeratin AE1AE3, IDH1; weak staining of P53; INI1 – retained (normal); Ki67 up to 5-10.

Revised diagnosis of CNS SFT was made for the 18-year-old case; diagnosis of metastatic SFT was made for the lung biopsy.

Conclusions: Diagnosing solitary fibrous tumor can be very challenging with a non-supportive clinical history. The key lead to the right diagnosis of our case is the classic H&E morphology, collaboration of intradepartmental consultation and revolution of immunohistochemistry staining markers.

Back To Top

 

P915 Reducing Atypical Diagnostic Rates in Biliary Brush Cytology

Susan McRae, Mariamma G. Joseph, Michele M. Weir.

Department of Pathology, London Health Sciences Centre, London ON.

Objective: ERCP guided biliary brushing is a simple, relatively safe technique for evaluating bile duct obstruction. These challenging specimens may result in high atypical diagnostic rates. Our study examines: 1) our atypical cytology diagnostic rate and outcomes; and 2) cytomorphologic features for atypical (atyp), suspicious (susp) and positive (pos).

Method: Reports of 348 biliary cytology specimens from 2013-16 were reviewed for diagnostic category and outcome (resection or endoscopic ultrasound fine needle aspiration (EUS-FNA)). One cytotechnologist (CT) blindly reviewed 75 cases (25 each atyp/susp/pos). Four CT and one pathologist (CP) blindly reviewed 12 cases (5 atyp/6 susp/1 pos). Cellularity (# abnormal groups and # atypical single cells) and nine other features were examined.

Data and Results: Our atypical diagnostic rate was 36% (127/348). 83 (64%) had follow up and 64 (77%) had a positive diagnosis (46 on resection, 18 at EUS-FNA). The range of # abnormal groups and # atypical single cells identified by one CT correlated with the original diagnoses. Four CT and one CP agreed on # abnormal groups and # single atypical cells for each diagnosis. Statistical significance was not found in any of the other nine features in predicting diagnosis.

Conclusions: Our atypical diagnostic rate is at the high end (12-40% in literature) with high # of positive diagnoses on follow-up. For one reviewer, increased # abnormal groups and # atypical single cells stratified into the diagnostic categories. This was reproduced by additional CT/CP reviewers. Other features reviewed did not assist with diagnosis stratification.

Keywords: biliary cytology, atypical, diagnostic rate

Back To Top

 

P916 Primary intestinal type adenocarcinoma of the endometrium

J. Alex B. MacNeila,b, Saul L. Offmana,b, Shawn K. Murraya,b.

aDivision of Anatomical Pathology, Nova Scotia Health Authority, Halifax, NS.
bAnatomical Pathology, Dalhousie University, Halifax, NS.

Background/Objective: Primary intestinal type adenocarcinoma of the endometrium is an exceptional entity, with few examples reported to date. Prior investigators have implied intestinal differentiation in a larger subset of endometrial carcinomas when focusing on the presence of enteric-type mucins, however the majority of these examples lacked characteristic intestinal histomorphology. Others have described tumors with intestinal histomorphology, but only as a component of otherwise conventional histotypes. There have been rare reports of primary endometrial adenocarcinoma with signet ring cells, however an association with a component of conventional endometrial adenocarcinoma was seen in the majority of cases. Herein we present a case of primary endometrial adenocarcinoma with exclusively gastrointestinal histomorphology, a component of signet ring cell differentiation, and gastrointestinal type immunohistochemical properties.

Case Presentation/Results: A 66 year old female presented with post-menopausal bleeding. Pelvic ultrasound noted thickened endometrium and endometrial biopsy demonstrated poorly differentiated adenocarcinoma with gastrointestinal-type features. She underwent hysterectomy, bilateral salpingo-oophorectomy and pelvic lymph node dissection, which showed similar histologic findings. Postoperatively, clinical work up for a possible extrauterine primary was performed, including a negative whole body PET-CT scan, and lower gastrointestinal endoscopy, which revealed only a single polyp reported as tubular adenoma (low grade).

Conclusion: An extragenital primary must be excluded in the context of an endometrial tumor with intestinal features. That being said, our findings establish that a primary endometrial adenocarcinoma must be included in the differential, even in the presence of intestinal mucinous histomorphology, signet ring cell differentiation, expression of enteric-type mucin stains and gastrointestional-type immunohistochemical stains.

Keywords: Endometrial carcinoma, intestinal type adenocarcinoma, signet ring cells

Back To Top

 

P917 Genetic of a primary high-grade neuroendocrine carcinoma of the trachea

Gurdip Singh Tambera, Victor Brochua, Jonathan Spicerb, Sophie Camilleri-Broëta, Derin Caglara, Roger Tabahc, Logan Walshd, Pierre-Olivier Fiseta.

aDepartment of Pathology, McGill University, Montreal, Quebec.
bDepartment of Thoracic surgery, McGill University Health Center, Montreal, Quebec.
cDepartment of General surgery, McGill University Health Center, Montreal, Quebec.
dRosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Quebec.

Introduction: Primary carcinomas of the trachea, especially neuroendocrine carcinomas (NEC), are rare malignancies. We present the case of a 64-year-old male ex-smoker, complaining of hemoptysis and found to have a tracheal mass on bronchoscopy. Tracheal resection revealed a polypoid high-grade neuroendocrine carcinoma (NEC) with limited superficial mucosal invasion.

Method: Immunohistochemistry (IHC) was performed with markers for neuroendocrine differentiation (CD56, synaptophysin and chromogranin), epithelial differentiation (TTF-1, Napsin and cytokeratins) and proliferation (Ki-67). Whole exome sequencing (WES) will later be carried out on DNA extracted from the formalin fixed paraffin embedded sections, and mutational analysis of the NEC will be performed with comparisons to neuroendocrine carcinomas from other sites.

Results: The main tracheal tumor showed neuroendocrine histology comparable to the neuroendocrine tumors of the lung, but with a markedly high mitotic rate (20 mitoses/10 high power field) and several zones of necrosis. IHC confirmed neuroendocrine differentiation and showed positive staining for CK7 and TTF1. The Ki-67 index was 70%. A focus of neuroendocrine hyperplasia showed similar immunohistochemistry findings. Surgical margins and locally excised lymph nodes were negative for carcinoma. Overall, the findings of the main tumour were consistent with a primary large cell neuroendocrine carcinoma of the trachea.

Conclusion: Few cases of primary high-grade NECs of the trachea have been described. The prognosis of this tumour is uncertain, even with a presumed complete resection. Exploration of the genomic landscape, through whole exome sequencing, of the tumour may elucidate its histogenesis. Similarly, comparisons to NECs from other body sites may yield prognostic informations.

Keywords: Neuroendocrine carcinoma/tumor, tracheal tumor, whole exosome sequencing

Back To Top

 

P918 Diagnostic rates before and after implementation of The Paris System for Reporting Urinary Cytology

Matthew Kubicaa, Wen Xieb, Alison Nella, Stephen Pautlerb, C. Meg McLachlina, Mariamma G. Josepha.

aDepartment of Pathology and Laboratory Medicine, London Health Sciences Centre and Western University, London, ON.
bDepartment of Urology, London Health Sciences Centre and Western University, London, ON.

Background: Urine cytology is an efficient method of diagnosing clinically occult urothelial carcinoma; however, until recently there were no standardized criteria for reporting urine cytology and over-reporting of “atypical” cases posed challenges for clinical management. In 2016, The Paris System for Reporting Urinary Cytology (TPS) was developed to standardize urine cytology reporting using set morphological criteria and diagnoses. TPS was implemented by the cytopathology division at London Health Sciences Centre (LHSC) in September 2016.

Methods: We compared urine cytology results from two time periods: before (September-December 2015) and after (September-December 2016) the implementation of TPS at LHSC. Statistical comparisons in rates of diagnostic categories were performed using chi-square analyses (P < 0.05 significant).

Results: 2576 urine cytology specimens were submitted during the study periods. The results are summarized as follows:

 

Sept–Dec 2015

Sept–Dec 2016

p-value

Total Cases

1317

1259

Negative for HGUC*

978 (74%)

1123 (89%)

0.002

Atypical Urothelial Cells

288 (22%)

115 (9%)

< 0.001

Suspicious for HGUC

29 (2.2%)

4 (0.3%)

< 0.001

Positive for HGUC

22 (1.7%)

17 (1.4%)

0.51

*High grade urothelial carcinoma

Discussion: Implementation of TPS at our institution has resulted in an increase in the proportion of negative cases reported, with a corresponding significant reduction in the number of atypical and suspicious cases. The proportion of positive cases did not differ between periods. It is likely that cases previously called atypical are now being reported as negative. Our results suggest that implementing TPS may provide clearer diagnostic direction for clinicians.

Keywords: urine cytology, Paris system, urothelial carcinoma, atypical urothelial cells

Back To Top

 

P919 Mismatch Repair Gene Immunohistochemistry in Products of Conception Can Diagnose Constitutional Mismatch Repair Deficiency

Mahdi Rahimi1, Marc R. Del Bigio2, Marc Dupre2, Charity Fan4, Stephanie Clarke4, Camelia Stefanovici2.

1Anatomical Pathology Residency, University of Manitoba.
2Department of Pathology, University of Manitoba/Diagnostic Services of Manitoba.
3Department of Biochemistry and Medical Genetics, University of Manitoba.

Introduction: The genomic stability is maintained by mismatch repair (MMR) genes. Heterozygous germline mutations in MMR genes cause Lynch syndrome. Bi-allelic mutations in MMR genes lead to constitutional mismatch repair deficiency (CMMRD), characterized by predisposition to hematological, brain and gastrointestinal malignancies in early childhood.

Clinical Presentation: We present comparatively the pattern of expression of MMR genes (proteins) by immunohistochemistry (IHC) on various tissue samples, i.e. maternal, both somatic and placental tissue, fetal, and brain tumor (glioblastoma). The child suffering of glioblastoma passed at age 3, and subsequently, molecular genetics studies made a diagnosis of Lynch syndrome (heterozygous MSH2 deletions) in both parents, albeit different alleles were involved. Mother had further both spontaneous and therapeutic terminations of pregnancies, as genetic testing identified one of products of conception compound heterozygote for two MMR mutations.

Results: MMR-IHC performed on glioblastoma and POCs showed loss of expression of MSH-2 and MSH-6 in brain tumor and non-tumor cells, as well as in fetal part of the chorionic villi (CMMRD); while the maternal tissue (endometrium, colon, decidua) showed intact expression for all four MMR proteins.

Conclusions: MMR-IHC staining of the products of conception can identify the CMMRD status, and offer a confident result to parents opting for pregnancy termination. Although this is an interesting observation, its clinical relevance and usage still needs to be determined by more studies.

Keywords: Lynch syndrome, constitutional mismatch repair deficiency, products of conception

Back To Top

 

P920 In situ follicular neoplasia: a clinicopathologic spectrum

G.S. Tamber, M. Chevarie Davis1, M. Warner2, C. Seguin2, C. Caron3, R.P. Michel1.

1McGill University, Department of Pathology, Montreal, QC.
2McGill University Health Centre, Division of Hematology – Department of Medicine, Montreal, QC.
3Hotel Dieu D’Alma, Department of Pathology, Alma, QC.

Objective: In situ follicular neoplasia (ISFN), an entity in the WHO classification since 2008, occurs in ≈2% of reactive lymph nodes. In the 2017 WHO, ISFN is set apart from “partial involvement by follicular lymphoma” (PFL). Although as sole finding, ISFN rarely progresses to overt lymphoma, the precise parameters to assess this risk remain incompletely explored.

Our aim was to examine the detailed microscopic features of ISFN/PFL in an attempt to predict risk of progression to overt lymphoma.

Methods: We reviewed 12 cases, 1 PFL, 11 ISFN between 2003 and 2017. H&E and immunohistochemical stains were reviewed. Follicles were scored (1A-3B) according to Jegalian et al (Blood,2011) and results of PCR/FISH analyses for t(14;18) recorded.

Data and Results: The PFL, scored 3B, was in a 57-year-old female who developed diffuse large B-cell lymphoma (DLBCL) 8 years later.

The 11 patients with ISFN included 7 males, 4 females; median age 64 years. Median follow-up was 2.2 (0-14) years. Ten were in lymph nodes, one in spleen. Of the 3 cases with ISFN scores 1A or 2A, all are alive with no other lymphoma. Of the 8 cases with scores 3A/3B, 2 had concurrent marginal zone lymphomas; another had progressive transformation of germinal centers and IgG4-related disease, all alive. One patient with ISFN score 3B had concurrent DLBCL and died shortly after diagnosis.

PCR/ FISH analyses in 6/12 cases: 1 patient with ISFN 3B had a translocation, no lymphoma.

Conclusions: Based on this limited series, we conclude that only cases with scores 3A/B are associated with an overt lymphoma, and that scoring may be a useful parameter to assess risk of associated lymphoma, and deserving further study.

Keywords: In situ follicular lymphoma, Diffuse large B-cell lymphoma, Follicular lymphoma, Marginal zone lymphoma

Back To Top

 

P921 Markers of prognostic significance in osteosarcoma: a tissue microarray-based immunohistochemical approach

Amal A. AlOdain1,2, M. Herman Chui2, Anthony M. Griffin3, Jay S. Wunder3, Elizabeth G. Demicco2, Brendan C. Dickson2.

1Department of Pathology, Imam Abdulrahman Bin Faisal University, KSA.
2Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, ON.
3Orthopedic Surgery, Mount Sinai Hospital, University of Toronto, ON.

Objective: Prognostic markers in osteosarcoma are limited. Recent gene expression studies have identified a number of markers of potential predictive value, including: RUNX2, REQL4, CDC5L, NFAT1, β-catenin, p16, CDK4, MDM2, CASP3, SATB2, P53 and MIB-1. The objective of this study is to determine whether these findings translate at the protein level by immunohistochemistry.

Methods: Using an osteosarcoma tissue microarray (46 pre-treatment; 48 post-treatment; 16 cases containing paired pre- and post-treatment), immunohistochemistry was performed for each of the aforementioned stains. Staining was quantified using a modified Allred scoring system. Factors examined were response to chemotherapy, local recurrence, overall survival, metastasis free survival. Statistical analysis was done via SPSS StatisticsV19.

Data and Results: Low pre-treatment p16 expression was found to predict a poor chemotherapeutic response (<90% treatment induced tumor necrosis, P-value 0.027). Local recurrence was associated with elevated CDK4 expression (P-value 0.007). None of the genes were found to be of prognostic value in determining the overall survival or metastasis free survival; however, there appeared to be a trend towards improved overall and metastasis free survival with several markers (elevated: p53, MDM2 and Caspase3; decreased: RUNX2 and β-catenin).

Conclusions: The results of this preliminary study suggest p16 expression may be of value in predicting a response to neoadjuvant chemotherapy, whereas CDK4 may predict local recurrence. Several markers suggested a trend towards significance in terms of improved overall and metastasis free survival. However, a larger sample size is required to more rigorously evaluate this possibility.

Keywords: Osteosarcoma, prognosis, predictive test, immunohistochemistry

Back To Top

 

P922 Everything but adenomata: 4 years’ experience of the British Columbia Colon Screening Program

Alisa Abozinaa, Laura Gentileb, Jennifer Telfordb,c, David F. Schaeffera,d.

aDepartment of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC.
bBC Colon Cancer Screening Program, Vancouver, BC.
cDivision of Gastroenterology, University of British Columbia, Vancouver, BC.
dDivision of Anatomic Pathology, Vancouver General Hospital, Vancouver, BC.

Introduction: The British Columbia Colon Screening Program (BCCSP) was implemented in November 2013 with the goal of reducing colorectal cancer mortality via the early detection of colorectal cancer and removal of its precursor lesions. In addition to this, various lesions of epithelial and mesenchymal origin have been incidentally discovered. This study focuses on lesions detected beyond the conventional adenomata.

Methods: The pathology of specimens collected through the BCCSP from November 2013 to December 2017 was assessed using data collected by the British Columbia Cancer Agency (BCCA).

Results: There were 88,541 colonoscopies performed in the period from November 2013 to December 2017. Most lesions (n = 55595, 51.6%) were tubular adenomata, followed by hyperplastic polyps (n = 21343, 19.8%), tubulovillous adenomas (n = 7100, 6.6%), sessile serrated adenomas (n = 5107, 4.7%), villous adenomas (n = 545, 0.5%), and traditional serrated adenomas (n = 271, 0.3%). Only 0.7% (n = 739) were adenocarcinomas. Eight percent (n = 8643) were normal, while 1.5% (n = 1658) showed only inflammation. The remainder (n = 6372, 5.9%) showed other pathology, including inflammatory polyps (n = 1020), mesenchymomas (n = 220), leiomyomas (n = 210), neuroendocrine tumours (n = 65), juvenile polyps (n = 56), Peutz-Jeghers polyps (n= 24), squamous cell carcinomas (n = 13), and one gastrointestinal stromal tumour.

Conclusions: In addition to the early detection of colorectal cancer and its precursors, the BCCSP has detected a variety of incidental non-adenomatous pathologies which has allowed for adequate patient assessment and follow up.

Keywords: Colorectal cancer, colonoscopy screening

Back To Top

 

P924 Mucosal neutrophilic infiltration assessed by flow cytometry reflects overall histologic severity in active Crohn’s Disease

Elizabeth Arslaniana, Amélie Therrienb, Laurence Chapuyb, Geneviève Soucya, Marika Sarfatib.

aDepartment of Pathology, Centre hospitalier de l’Université de Montréal, Montreal, QC.
bImmunoregulation Laboratory, Centre de recherche du Centre hospitalier de l’Université de Montréal, Montreal, QC.

Objective: Literature shows conflicting correlations between histologic and endoscopic severity in Crohn’s disease (CD) and no data correlating colonic neutrophilic infiltration assessed by histology and flow cytometry with disease severity. We hypothesize that neutrophilic infiltration in the mucosa would reflect disease severity.

Methods: We selected 24 patients with colonic or ileocolonic CD out of a prospective cohort of 72 adults according to their Simple Endoscopic Score for Crohn’s Disease (SES-CD) determined at the time of colonoscopy. We blindly reviewed the biopsy slides (HE or HPS, 3 levels) according to an adaptation of the Global Histologic Disease Activity score (GHAS). We assessed frequencies of peripheral blood and mucosal neutrophils by flow cytometry. We analyzed data using nonparametric tests (Spearman rank correlation coefficient, Mann-Whitney U test and Kruskal-Wallis H test).

Data and Results: Histologic score was significantly higher in patients with endoscopic active disease (SES-CD ≥ 3; n = 19) than in endoscopic remission (SES-CD < 3; n = 5) (p < 0.01). Within the active disease group, histologic and endoscopic severity did not correlate (r = 0.18). The importance of neutrophilic infiltration in the epithelium and in the lamina propria did not differ according to endoscopic severity. Histologic score positively correlated with neutrophilic infiltration in the mucosa (r = 0.51; p < 0.03) and negatively correlated with the frequency of circulating neutrophils (r = -0.48; p < 0.05) assessed by flow cytometry.

Conclusions: Colonic mucosal neutrophilic infiltration assessed by flow cytometry reflects overall histologic severity in active CD in adults.

Keywords: Crohn; colitis; neutrophil; GHAS, flow cytometry

Back To Top

 

P926 High-Grade B-cell Lymphoma NOS in a Patient with Williams Syndrome

Sadaf Memon1, Rosemarie Tremblay-LeMay2, Jan Delabie2.

1Department of Pathology & Molecular Medicine, McMaster University, Hamilton, ON.
2Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, ON.

Introduction: Williams syndrome (WS) is rare neurodevelopmental disorder with cardiovascular malformations, caused by a constitutional deletion of chromosome 7q11.23. The occurrence of Burkitt Lymphoma and acute lymphoblastic leukemia in Williams syndrome has sporadically been reported in the literature.

Clinical Presentation: We herein describe the case of a 29 year-old male with WS who presented with a one-year history of fatigue, 10 Ibs of weight loss and worsening odynophagia for 5 months. On physical exam there was an enlarged right tonsil. The symptoms were unresponsive to antibiotics, therefore the patient was referred for malignancy work-up. The CT scan of the head and neck revealed bilateral enlarged palatine tonsils. There was also an enlarged cervical lymph node demonstrating early central necrosis on imaging. An incisional biopsy of the tonsil was performed for diagnosis.

Results: The tonsil epithelium showed focal ulceration. The underlying submucosa showed diffuse infiltration by intermediate cells with high nuclear cytoplasmic ratio and irregular nuclei with several nucleoli. Numerous apoptosis cells were present. The atypical cells expressed CD20, CD10(100%), BCL-6 (100%) but not MYC (15%), BCL-2, MUM-1, CD5, CD23, CD30 and EBV. The proliferation index by Ki-67 was 100%. FISH could not demonstrate MYC, BCL-2 or BCL-6 gene translocations. A final diagnosis of high-grade B-cell lymphoma NOS (HGBL- NOS) was made.

Conclusions: WS is not considered as a cancer predisposing condition. However, the current case as well as the previously reported cases of Burkitt and acute lymphoblastic leukemia suggest an increased incidence of aggressive B cell malignancies.

Keywords: Williams syndrome, High-grade B-cell lymphoma NOS

Back To Top

 

P927 MUC6 and HIK1083 Expression in primary ovarian mucinous and endometrioid carcinomas

Dina Bassiouny1, Matthew Cesari1, Fang-I Lu1, Elzbieta Slodkowska1, Bojana Djordjevic1, Jelena Mirkovic1,Sharon Nofech-Mozes1, .

1Division of Anatomic Pathology, Department of Laboratory Medicine and Molecular Diagnostics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON.

Objective: Expression of MUC6 and HIK1083 has been reported mainly in gastric glands, subset of gastrointestinal carcinomas and endocervical gastric type adenocarcinoma, with HIK1083 being more specific. These markers may help distinguish metastases from primary ovarian mucinous (OMC) and ovarian endometrioid carcinomas (OEC). We investigated MUC6 and HIK1083 expression in OMC and OEC.

Method: Expression of MUC6 and HIK1083 in 38 OMC and 70 OEC was studied by immunohistochemistry (Fig. 1).

Data and Results: MUC6 expression is summarized in Table 1. HIK1083 was focally positive in 4 (10.5%) OMC (3 moderate, 1 strong intensity) and negative in all OEC.

Table 1:

MUC6 Expression
(Intensity)

Negativ

Focal
(W, M, S)

Diffuse
(W, M, S)

Total

OMC

34

0, 1, 2

0, 0, 1

38

OEC

50

1, 2, 4

1, 1, 11

70

W: weak, M: moderate, S: strong

– click here for figure

Conclusions: Diffuse MUC6 expression may be seen in primary OMC and OEC. Focal HIK1083 expression was observed in some OMC. Therefore, MUC6 and HIK1083 may be useful in the context of differentiating metastatic from primary ovarian tumors, especially since OMC are ER/PAX8 negative.

Keywords: Immunohistochemistry, MUC6, HIK1083, ovarian carcinomas

Back To Top

 

P928 Evaluation of the prognostic impact of pyknotic nuclei in prostate cancer cells: a retrospective cohort study

Mame-Kany Diopa,b, Véronique Ouelleta, Nazim Benzerdjebc, Mathieu Latourd, Roula Albadined, Armen G. Aprikiane, Louis Lacombef, Neil E. Fleshnerg, Martin E. Gleaveh, Anne-Marie Mes-Massona,b,d, Fred Saada,d,i, Dominique Trudela,b,d.

aCentre de Recherche du Centre Hospitalier de l’Université de Montréal and Institut du Cancer de Montréal, Montreal, QC.
bDepartment of molecular biology, Université de Montréal, Montreal, QC.
cCentre hospitalier Lyon Sud, Lyon, France.
dDepartment of Pathology, Centre Hospitalier de l’Université de Montréal, Montreal, QC.
eResearch Institute of McGill University Health Center and Department of Surgery (Urology), McGill University, Montreal, QC.
fCHU de Québec, Quebec City, QC.
gDivision of Urology, Department of Surgery, University Health Network, University of Toronto, Toronto, ON.
hVancouver Prostate Centre & Department of Urologic Science, University of British Columbia, Vancouver, BC.
iDepartment of Surgery, Université de Montréal, Montreal, QC.

Objective: Despite the early diagnosis of non-metastatic prostate cancer (PCa), a large variation in survival rate is observed. It is imperative to find new prognostic factors to better guide the treatment of PCa. In a preliminary study we found that a higher percentage of cells with pyknotic nuclei was observed in the more aggressive cancers. Our goal is to assess the prognostic potential of pyknotic nuclei in PCa.

Method: Stained with hematoxylin and eosin, the tissue microarrays of a test cohort of 250 patients, and a validation cohort of 1262 patients, were analyzed to visually estimate the amount of cells with pyknotic nuclei among the cancer cells. Patients were classified into 2 categories according to the estimated percentage of pyknotic nuclei.

Data and Results: More pyknotic nuclei were observed in patients with positive surgical margins (p=0.001), lymph node metastases (p=0.004), extraprostatic extension (p=0.018), and seminal vesicle involvement (p=0.024). In addition, the survival rate without biochemical recurrence (BCR) is shorter in patients with a higher amount of pyknotic nuclei and a Gleason score (GS) of 3+4 (p=0.041). From a further study on whole slides (N=5), the distribution of pyknotic nuclei was not always homogeneous in the tumor.

Conclusions: Pyknotic nuclei are linked to adverse prognostic factors and associated with poor prognosis in patients with a GS of 3+4. However, because of the heterogeneous distribution of pyknotic nuclei across the complete tumor, quantifying pyknotic nuclei in whole sections is necessary.

Keywords: Prostate cancer, prognosis, biochemical recurrence, nuclei

Back To Top

 

P929 Lésion mammaire inusuelle mimant un cancer

Kenza. Oqbani1, Laila. Bahi1, Sanae. Abbaoui1.

1Service d’anatomie et de cytologie pathologiques, CHU Mohammed VI, Oujda.

Introduction- Objectif : La mastopathie diabétique (MD) est une lésion trompeuse rare, faite d’une prolifération pseudotumorale du tissu fibreux mammaire, survenant chez des patientes diabétiques. Notre objectif est de mettre le point sur les aspects cliniques et radiologiques trompeurs de cette lésion et de souligner le rôle clef de l’anatomopathologie.

Observation : Mme K.H âgée de 52 ans, suivie pour un diabète de type II depuis 20 ans sous antidiabétiques oraux bénéficiait il y a 4 ans d’une biopsie d’une tumeur mammaire droite. L’histologie objectivait des remaniements fibro-inflammatoires sans signe de malignité. La patiente était perdue de vue jusqu’à l’apparition de gonalgie d’allure inflammatoire. L’examen clinique trouvait un nodule du QSE du sein droit de 2 cm de grand axe. Le bilan biologique révélait un syndrome inflammatoire et une hyperglycémie à jeun à 1,53g/dl. Cette tumeur était classée ACR 4 à la mammographie/échographie. L’étude histologique de la pièce de tumorectomie confirmait le diagnostic de MD.

Discussion/ Conclusion : La MD représente moins de 1% des lésions bénignes du sein en association avec un diabète de type 1. Jusqu’au 2006, 35 cas de MD sont rapportées chez des patientes diabétiques type II. Sa pathogénie reste obscure. L’aspect radiologique simule celui d’un cancer mammaire. Le diagnostic de MD doit être évoqué devant toute lésion mammaire suspecte chez les patientes diabétiques quelque en soit le type. La chirurgie devrait être évitée devant les aspects typiques de MD à la biopsie chirurgicale, à cause d’un taux de récidive de 60 % après exérèse chirurgicale.

Keywords : mastopathie diabétique, diabète, cancer du sein, histologie

Back To Top

 

P930 Lymphocytic gastritis: etiology and disease associations

Sandy (Si Kei) Lou1, Rajkumar Vajpeyi2.

1Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.
2Department of Pathology, Toronto General Hospital, University of Toronto, Toronto, ON.

Objective: To determine the etiology and disease associations of lymphocytic gastritis (LG).

Methods: We reviewed pathology reports and clinical notes of patients diagnosed with LG at University Health Network between January 2000 to April 2017. Patients were classified based on established and possible new etiologic causes of LG via clinicopathologic integration.

Data and Results: Ninety-six patients were diagnosed with LG. In 64 patients (66.7%), an etiologic factor was identified, including 24 with celiac disease, 11 with HP gastritis, 2 with lymphocytic colitis, 2 with inflammatory bowel disease, 1 with human immunodeficiency virus infection, 1 with combined variable immunodeficiency, 8 with gastric malignancies (primary or metastatic) and 15 patients with distinct disease associations not previously described (5 on nonsteroidal anti-inflammatory drugs, 1 with food allergy, 4 with cirrhosis, 2 with renal transplant and 3 with esophageal pathologies). Thirty-two patients had gastric biopsies from the body and antrum. Regardless of disease association, LG seems to be a diffuse process involving both antral- and oxyntic-type mucosa.

Conclusions: LG is a descriptive pathologic diagnosis with many underlying disease associations. We describe five previously undescribed possible etiology of LG. A pathologic diagnosis of LG is a diagnostic clue, mandating a further work-up to elucidate an etiologic cause.

Keywords: Lymphocytic gastritis

Back To Top

 

P931 Management of breast cancer patients with equivocal HER2 results: a single institution retrospective study

Alexandra Gauthier-Bastiena, Claudie Paqueta, Michèle Oraina, Jean-Charles Hoguea, Nathalie Laflammeb and Ion Popaa.

aCHU de Québec – Université Laval, Quebec City, Province of Quebec.
bClinical and evaluative research platform, CHU de Québec – Université Laval Research Center, Quebec City, Province of Quebec.

Introduction and objectives: The 2013 American Society of Clinical Oncology and College of American Pathologists guidelines regarding the interpretation of HER2 results for breast cancer modified the definition of an equivocal result. It also stated that HER2-targeting therapy could be used in this population, without providing criteria to support the decision. The aims of this study were to identify, at our institution and considering the 2013 guidelines, the proportion of patients with equivocal HER2 results, the proportion of those patients treated with targeted therapy, and factors supporting the treatment decision.

Methods: A retrospective study of breast cancer diagnosis at CHU de Québec – Université Laval between 05/01/2014 and 10/31/2017 was performed. The list of patients and their clinical data were obtained using our electronic charts.

Data and Results: 2867 patients received a breast cancer diagnosis at our center during the study period. HER2 results were positive for 415 (14.5%), negative for 2344 (81.8%) and equivocal for 108 (3.8% vs. 1.7% before 2013). From the 105 equivocal cases with follow-up data available, 9 (8.6%) were not candidate to chemotherapy because of comorbidities and 8 (7.6%) declined chemotherapy. Eight patients (7.6%) received HER2-targeting therapy. Their clinical data were heterogenous and we did not find any specific factors supporting the decision of treatment.

Conclusion: At our institution, the proportion of breast cancer diagnosis with equivocal HER2 results increased with the 2013 guidelines change. 7.6% of equivocal cases received HER2-targeting therapy. No clinico-pathologic factors supporting the therapeutic decision in those equivocal cases were identified.

Keywords: breast cancer, HER2, equivocal, HER2-directed therapy

Back To Top

 

P932 Significance of subtractive coordinate immunoreactivity pattern (SCIP) approach in diagnostic cytology of serous fluid

Kashan Khalid, Joshua Jeanty, Rabitta Dugu, Vinod B Shidham.

Wayne State Medical University, Detroit Medical Center, Detroit, MI, 48088, USA.

Background: Body fluid cytology is one of the most challenging areas in diagnostic cytopathology. The most important issue to be considered when applying immunohistochemistry to the body fluid specimen is the significant variation in results due to many variables. One significant challenge associated with immunohistochemistry of body fluid with scant cellularity is the intricacy of finding and locating cells of interest (diagnostic component) in the cell block sections. This requires a dedicated and careful approach for reproducible and accurate interpretation of results not elaborated in routine cytology literature. We have studied Subtractive Coordinate Immunoreactivity Pattern (SCIP) approach for the immunohistochemistry to analyze the results in body fluid specimens specifically for the ones with low cellularity. SCIP allows construction of a topographic map of various components in the specimen.

Method: We revisited 25 body fluid cytology cases with very low cellularity (18 pleural fluids, and 7 peritoneal fluids) from 2011 to 2017. IHC, some with dual color immunostaining (cocktail) were reviewed with and without SCIP approach. In SCIP approach, sequential serial sections were oriented identically for reproducible tracking of the relative positions of different cells. This allows evaluation of coordinate immunoreactivity pattern of various cellular components in the specimen. A battery of IHC to differentiate the reactive mesothelial cells along with other inflammatory cells was performed including vimentin. A panel of three pathologists reviewed the cases individually. To study the interobserver reproducibility with and without SCIP, time difference during interpretation of specimen was studied.

Results: After the assessment of all cases, it was noted that SCIP approach showed 100% accuracy and reproducibility among 3 interpreters while without SCIP approach cases showed 23 out of 25 cases with the same interpretation. 2 out of 25 cases showed discrepancy (92% accuracy and reproducibility). A chi-square test to compare the ratios with SCIP vs without SCIP was performed. In addition, 95% confidence interval for the difference between ratios is 0.65 to 1. The turnaround time was significantly prolonged (approximately 93 minutes more) for those cases which were reviewed without SCIP approach.

Conclusion: Body fluid cytology combined with SCIP approach for the immunohistochemical staining improves the diagnostic accuracy and reproducibility in cases with few or scattered cells of interest. SCIP approach allows easy tracking of tumor cells in a busy background of the reactive component of a specimen with limited diagnostic material and quicker to interpret.

Back To Top

 

P933 Thyroid cytology: has liquid-based cytology decreased the number of unsatisfactory thyroid fine needle aspirates?

Christine E. Orra, Charles Leducb, David Hurlbuta, Marosh Manducha.

aDepartment of Pathology and Molecular Medicine, Queen’s University, Kingston, Ontario.
bDepartment of Pathology and Cell Biology, University of Montreal, Montreal, Quebec.

Objective:Evaluate the percentage of unsatisfactory samples from thyroid fine needle aspirates (FNA) via liquid-based preparation (LBP) versus conventional smear (CS).

Methods: Diagnoses from thyroid FNA CSs September 2009 to December 2012 (n=652) and thyroid FNA LBPs January to December 2016 (n=559) at our institution were correlated with FNA site (academic vs community) and operator (radiologist vs clinician).

Data and Results: Overall percentages of unsatisfactory thyroid FNAs were significantly higher in the LBP (201/559) vs CS cohorts (188/652) (p=0.0095). When corrected for site and operator, this trend was only seen in FNAs obtained by the academic radiology department (LBP 63/189; CS 28/203; p=<0.00001). FNAs obtained in the community (LBP 84/206; CS 114/284; p=0.9258) or the academic clinic (LBP 53/164; CS 19/74, p=0.361) showed no significant differences in unsatisfactory rates. Community obtained FNAs had more unsatisfactory samples compared to FNAs from the academic center (LBP 112/353; CS 47/277) in both the LBP (p=0.0346) and CS (p<0.00001) cohorts. FNAs obtained in the academic radiology department compared to the academic clinic had fewer unsatisfactory samples in the CS cohort only (p=0.0289) with no significant difference in the LBP cohort (p=0.9096).

Conclusions: Our results suggest community obtained FNAs yield more unsatisfactory results than those from the academic center independent of the cytological preparation. Furthermore, only samples from the clinical radiology department displayed a significant difference between the two preparations; however, the cohorts were obtained at different time periods, and may represent a change in radiology personnel suggesting unsatisfactory thyroid FNA rates are operator/site dependent and independent of the FNA preparation.

Keywords: Thyroid, Cytology, Liquid Based Preparation, Conventional Smear

Back To Top

 

P934 Country music video: a novel tool for pathology teaching

Matthew J. Cecchini, Joanna C. Walsh.

Department of Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, Western University, London, ON.

Objective: To assess the learning impact on viewers and creators of a music video about the pathology of celiac disease.

Methods: In collaboration with four second year medical students, a country music video was created and shown to one of two groups of third year medical students in conjunction with a pathology lecture. Students in the control and study groups completed an online quiz immediately after the lecture and again at 2 weeks.

Results: Students who watched the video were more likely to complete the quiz (32% vs 23% immediate and 21% vs 17% at 2 weeks). Overall percentage scores were higher for students who watched the video (88% vs 76% immediate and 73% vs 71% at 2 weeks). Students who watched the video at home after class had the highest overall percentage score (83% at 2 weeks). Ninety-one percent reported a positive learning experience. Students who created the video stated that they learned new facts about celiac disease, that they had shared the video with other healthcare professionals, had thought about their professional role and what they would be prepared to share with patients with a certain condition, and that creation of the video had helped them to reduce their own stress.

Conclusions: The country music video is a novel teaching tool for re-inforcement of pathology and improves immediate and delayed fact recall. Given the benefits to viewers and creators, more opportunities should be offered to medical students to use their creative talents as an adjunct to curricular learning.

Keywords: pathology; country music; video; medical education

Back To Top

 

P935 Malignant soft tissue tumors: A case series diagnosed by Fine Needle Aspiration Cytology in a tertiary care hospital in Canada

T. Truonga, C. Ghosha.

aLaboratory Medicine, Eastern Health and Memorial University, St John’s, Newfoundland.

Malignant soft tissue tumors (MSTT), unlike the benign counterpart, is far less common in clinical practice. They also have complex light microscopic features with heterogeneous compositions, posing diagnostic challenge, especially in fine needle aspiration cytology (FNA) sample. This study presents a series of MSTT cases diagnosed in cytology, Eastern Health, St John’s, Newfoundland between 2014 and 2016.

FNA material collected by image guided aspiration technique, was processed using liquid based (SurePath) cytology method and cell block preparations. 8 cases of MSTT presented are Ewing Sarcoma, Proximal Epithelioid Sarcoma, Chondrosarcoma, Epithelioid Angiosarcoma, Metastatic Uterine Carcinosarcoma, Undifferentiated spindle malignant tumor and Undifferentiated pleomorphic sarcomas with rhabdomyosarcoma component (UPSRS). Concurrent or subsequent core biopsy and/or resected material with relevant immunostains were correlated with cytological diagnosis.

There is 100% concordance between FNA diagnosis and corresponding core biopsies in all presented cases. 5/8 cases have concordant diagnoses of FNA, core biopsy and resected material. Resected specimens are not available for one case of Ewing sarcoma and that of Angiosarcoma where patients only received palliative radiotherapy. In one case, a diagnosis of Pleomorphic Rhabdomyosarcoma was made by FNA and the correlated core biopsy whereas URSRS was made on the final resected specimen. This discrepancy is attributed to small sample size in FNA and core biopsy leading to equivocal interpretation of certain immunostains.

We demonstrate that Image guided FNA is a useful tool for diagnosing soft tissue sarcoma. Accurate clinical, radiological information, adequate sampling for routine morphologic examination and ancillary tests are keys to the success.

Keywords: Angiosarcoma, Carcinosarcoma, Chondrosarcoma, Ewing Sarcoma, Fine Needle Aspiration

Back To Top

 

P936 Scedosporium species identified in bronchial brushing cytology ten years post-transplant

Laura Canterbury1,2, Idowu J. Adekanmbi1,2.

1University of Alberta, Edmonton.
2Alberta Health Services, Edmonton.

Introduction: Scedosporium are ubiquitous filamentous fungi present in soil, sewage and polluted waters1. Known species includes; S.boydii, S. apiospermum and S.auratiacum. Among wide spectrum of conditions caused by Scedosporium are; airway colonization, sinopulmonary infections, extrapulmonary infections, mycetoma and disseminated diseases.1,2,3

Scedosporium causes resistant life-threatening infection commonly in immunocompromised hosts with associated with high mortality rate in lung transplant patients.4

We report a case of persistent scedosporium infection, 10 years post-transplant in a 74-year-old male.

Case Report: 74-year-old male presented with increased cough and sputum and increase work of breeding. Pulmonary functions test shows decrease in FVC with evidence of airflow obstruction. Chest Xray shows cavitary lesion in the left upper lobe as well as tree in bud appearing changes. Initial fungal culture of bronchial washing reveals presence of scedosporium species. He was started on posaconazole . Subsequent CT chest although stable continue to demonstrate thick walled cavitary lesions. Bronchial wash for cytology was received five months after initiation of antifungal.

Results: Figures 1a-1b: flask shaped annelides

– click here for figure

Conclusion: Scedosporium is an opportunistic fungal pathogen that is increasingly becoming a cause of serious infection in severely ill or immunocompromised patients especially in solid organ transplant. Two members of this genus; S. apiospermum and S.prolificans are the major pathogens in humans.1

Septate hyphae bearing conidiophores and flask shaped annelides with background inflammation or granulomata is an important clue.1.Identification of scedosporium is of clinical importance as this organism compared to other pathogenic fungi is resistant to Amphoterin B and some Azoles.3,4 The mortality rate among organ transplant recipients is about 50%.5 Efficacy rate with Voriconazole is only 30% and utility of combination therapy in the treatment of scedosporidiosis is unknown.2,5

References:

1Gordon Lee Love. 2015; Pathology of Infectious Diseases ch. 23, pgs461-490

2Eszter J Toth, Geza R.Nagy, Monika Homa , Marianna Ábrók, Ildikó É. Kiss, Gábor Nagy, Zsuzsanna Bata-Csôrgõ, Lajos Kemény, Edit Urbán, Csaba Vágvôlgyi and Tamás Papp. 2017: Recurrent Scedosporium apiospermum mycetoma successfully treated by surgical excision and terbinafine treatment: a case report and review of the literature; Annals of Clinical Microbiology and Antimicrobials.

3Al Refai, M., C. Duhamel, J. P. Le Rochais, and P. Icard. 2002. Lung scedosporiosis: a differential diagnosis of aspergillosis. Eur. J. Cardiothorac. Surg. 21:938–939

4Rishi Raj, MD; and Adaani E. Frost. 2002; Scedosporium apiospermum Fungemia in a Lung Transplant Recipient

5Shahid Husain Patricia Muñoz Graeme Forrest Barbara D. Alexander Jyoti SomaniKathleen Brennan Marilyn M. Wagener Nina Singh. 2005; Clinical Infectious Diseases, Volume 40, Issue 1, Pages 89–99

Back To Top

 

P937 Human bowel tissue sampling to support gastrointestinal research: Experience of a pathology-centred protocol at Kingston Health Science Centre

May-Phyo Nyi Nyi1, Celine Morissette2, David Reed2, Michael Blennerhassett2, Stephen Vanner2, David Hurlbut1,2.

1Department of Pathology and Molecular Medicine, Kingston Health Science Centre (KHSC) and Queen’s University, Kingston, Ontario.
2Gastrointestinal Diseases Research Unit (GIDRU), Kingston Health Science Centre (KHSC) and Queen’s University, Kingston, Ontario.

Background: Most tissue in bowel resection specimens is not directly needed for surgical pathology diagnosis and could be utilized for research. The pathologist is the “gate-keeper” in managing sampling of human tissue for research to protect specimen diagnostic value.

Objective: Obtain fresh tissue samples from surgically resected bowel specimens to improve accessibility of human tissue to support gastrointestinal (GI) research.

Methods: Ethics approved pathology-centred protocol was developed for collection of fresh human bowel tissue samples from elective surgical resection specimens at our institution. The protocol included patient consenting and pathology control of specimen receipt, assessment and sampling. We report our experience with the first 100 surgical specimens using this protocol.

Results: We achieved 99% patient consent for tissue sampling. No specimen was available for sampling in 13 cases (surgery cancelled or aborted – 2; surgery went after hours – 11). Tissue sampling occurred in 93% (80/86) of specimens received. Reasons for sampling failure included risk of impairing surgical pathology diagnosis and lack of researcher availability for specimen pickup. Sampled resection specimens provided 120 fresh tissue samples supporting 4 GIDRU researchers and 1 university study. A single resection specimen supported multiple research studies in 17.5% (14/80) of cases, including 7 specimens that provided samples to 3 labs.

Conclusion: Using an ethics approved pathology-centred protocol, we obtained human bowel tissue samples from surgical resection specimens to support GI research. Patient participation was almost universal and ability to obtain tissue samples without compromising diagnostic ability was high. Pathology control of tissue sampling is mandatory to maintain the diagnostic value of each specimen.

Keywords:

Back To Top

 

P938 Abnormal/wild type p53 expression in bladder cancer shows better correlation with FGFR3 mutation status than the commonly used 10% p53 cut-off

Anjelica Hodgsona,b, Bin Xua,b, Bas W.G. van Rhijnc, Theo van der Kwastb,d, Michelle R. Downesa,b.

aSunnybrook Health Sciences Centre, Toronto, ON,.
bDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.
cDepartment of Surgical Oncology (Urology), Netherlands Cancer Institute – Antoni van Leeuwenhoek Hospital, Amsterdam, Netherlands.
dUniversity Health Network, Toronto, ON.

Objective: p53 immunohistochemistry is often used as a surrogate for TP53 mutation status. A 10% staining cut off has traditionally been used in the evaluation of high grade urothelial carcinoma (HGUC) for designation as p53 positive/negative, however recent work has shown that an alternate method (0% or >50% – abnormal or 1-49% – wild type) has significant correlation with oncologic outcome. FGFR3 mutations are frequent in the low grade pathway of UC and should be virtually mutually exclusive of HG pathway TP53 mutations. We hypothesized that the alternate method of p53 assessment would show better correlation with FGFR3 mutation status than the traditional 10% cut off.

Methods: Tissue microarray sections from two HGUC cohorts (cystectomy and pT1 arrays, n=102 and 56, respectively) were stained with p53 and scored by two blinded reviewers. Both 10% and abnormal/wild type cut offs were applied. Each case was analyzed for FGFR3 mutation status. Fisher’s exact test was used for statistical analysis.

Data and Results: 11% and 32% of cases were FGFR3 mutated in the cystectomy and pT1 groups, respectively. In the cystectomy group, 72% and 52% of cases were p53 positive using the 10% threshold and alternate scoring method, with the latter showing significant correlation with FGFR3 mutation status (p=0.003). In the pT1 group, 88% and 57% were p53 positive using 10% threshold and alternate scoring method, with the latter showing significant correlation with FGFR3 mutation status (p=0.021).

Conclusions: Abnormal/wild type p53 staining in HGUC shows significant correlation with FGFR3 mutation status and outperforms the traditionally employed 10% cut-off.

Keywords: bladder cancer, p53, FGFR3, immunohistochemistry

Back To Top

 

P939 Rate of Atypical Urothelial Cells Diagnosis in 2017 After Implementation of The Paris System for Urinary Cytology

Thomas Shia, Matt Kubicaa, Catherine M McLachlina, Alison Nella, Mariamma G. Josepha.

aDepartment of Pathology and Laboratory Medicine, London Health Sciences Center, London, Ontario.

Objective: Urine cytology is an efficient way to detect high grade urothelial carcinoma. The Paris System for Reporting Urine Cytology (TPS) was implemented in 2016 to standardize the terminology and diagnostic categories. Past research has shown the Atypical Urothelial Cells (AUC) rate significantly decreased after implementation of TPS at LHSC. We wish to investigate to see if this drop in AUC rate is sustained in 2017.

Methods: Collect urine cytology data for 2017, analyze rate of each diagnostic category. Use chi-squared test to assess for any statistically significant difference.

Results: no statistically significant difference was detected amongst all 2017 quarters (Chi squared = 6.14, p = 0.7262).

Discussion: drop in AUC rate is sustained in 2017 at LHSC. AUC rate for urine cytology could become a performance indicator in the future akin to thyroid cytology.

Keywords: urine, cytology, The Paris System, Atypical Urothelial Cells

Back To Top

 

P940 An epidemiological analysis of myelodysplastic syndromes in the Calgary Metropolitan Area

J. Slacka, L. Nguyena, C. Nauglera,b, F. Rashid-Kolveara,b.

aDepartment of Pathology and Laboratory Medicine, University of Calgary, Calgary, AB.
bCalgary Laboratory Services, Calgary, AB.

Introduction/Objective:

Methods: All bone marrow samples for a population of 1.4 million people were assessed over a five-year period, and further analyzed by flow cytometry and light microscopy to identify MDS using the revised 2008 World Health Organization criteria. All cases were confirmed by cytogenetic testing. 176 new cases of MDS were identified, and further categorized by sex and 5-year age groups. Incidence rates were calculated using population data taken from Statistics Canada’s CANSIM database.

Results: The crude incidence rate was 2.60 cases per 100,000 person-years. The median age at diagnosis was 75 years, with a male to female ratio of 1.35. The calculated age-standardized incidence for Canada was 3.69 cases per 100,000 person-years.

Conclusions: The incidence, age and sex distribution were similar to those of the US, Western Europe, Japan, and several developing nations. This is the first study to provide an epidemiological analysis of myelodysplastic syndromes within Canada, and may serve as a baseline for future comparison. This information can be used to help establish health policy at both provincial and national levels, and would predict 1295 new cases of MDS per year in Canada

Keywords: myelodysplastic syndromes, incidence, hematological malignancy, epidemiology

Back To Top

 

P941 Botryomycosis in an immunocompetent individual: a case report

Kaitlin A. Vanderbecka, Ami Wanga, John Davidsonb, Iain Younga.

aDepartment of Pathology and Molecular Medicine, Queen’s University and Kingston Health Sciences Centre, Kingston, ON.
bDepartment of Plastic Surgery, Queen’s University and Kingston Health Sciences Centre, Kingston, ON.

Objective: Botryomycosis is a rare, primarily cutaneous, chronic bacterial infection that occurs principally in the immunocompromised. This case study serves to heighten awareness among pathologists that botryomycosis may also occur in apparently immunocompetent individuals and highlight the key morphologic features that enable its diagnosis.

Methods: An analysis of the patient’s medical records, histologic findings and microbiologic testing was completed and a literature review was performed.

Data and Results: A 48 year old, otherwise healthy woman presented with a 4 cm nodular mass on the dorsum of her hand. The mass was excised and histology revealed extensive subcutaneous suppurative granulomatous inflammation associated with numerous foci of the Splendore-Hoeppli phenomenon. Gram-positive cocci with morphologic features consistent with Staphylococcus aureus were identified, establishing a diagnosis of botryomycosis. An attempt to identify the bacterial species by molecular analysis of the paraffin-embedded tissue was unsuccessful.

Conclusions: “Botryomycosis” is a misnomer, as it is a bacterial, not fungal, infection. Staphylococcus aureus is the most common etiology and the presumed cause in this case. Botryomycosis should be differentiated from conditions that present with similar clinical features, including mycetoma, actinomycosis and tuberculosis. Its histologic diagnosis depends on the identification of causative bacteria but is enabled by the recognition of an active chronic inflammatory reaction, typically associated with suppuration, and the Splendore-Hoeppli phenomenon. Importantly, botryomycosis is not solely a disease of the immunocompromised and may develop in immunocompetent people.

Keywords: Botryomycosis, Splendore-Hoeppli phenomenon, Staphylococcus aureus

Back To Top

 

P942 An unique case of mixed phenotype T/myeloid sarcoma with epitheliotropism mimicking intestinal T cell lymphoma

Carol Wanga, Diponkar Banerjeea, Philip Berardia, Bruce F. Burnsa, Luke Shierb, Aleksandra Paligaa.

aDivision of Anatomical Pathology, Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, ON.
bDivision of Hematopathology, Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, ON.

Introduction: Myeloid sarcomas and extramedullary manifestations of mixed phenotype acute leukemia (MPAL) without leukemic involvement are rare. We present an unusual case of myeloid sarcoma of T/myelomonocytic biphenotypic nature and BCR-ABL translocation demonstrating an epitheliotropism in the gastrointestinal tract and mass-forming lesions in the lungs without bone marrow involvement.

Clinical Presentation: A 69 year old gentleman presented with non-bloody diarrhea and abdominal pain complicated by a fifty pound weight loss. Infectious etiologies were ruled out and serum anti-tissue transglutaminase IgA antibody was negative. CT scan showed diffuse mural thickening in the jejunum, distal ileum, transverse colon and splenic flexure in addition to bilateral pulmonary nodules. Biopsies of the ileum, colon and lung mass were performed and sent for flow cytometry.

Results: An infiltrate of monomorphic medium sized atypical cells with marked epitheliotropism were noted in the intestine. These cells were positive for CD4, CD7, CD34 (subset), CD68, muramidase/lysozyme and CD117. Flow cytometry showed an aberrant myelomonocytic population with variable immaturity. A distinct subset of blasts with strong cytoplasmic CD3 was identified, confirming the presence of T lineage blasts. The diagnosis of mixed phenotype T/myeloid sarcoma with myelomonocytic differentiation was made.

Conclusion: Epitheliotropism has not been described in literature as a histologic feature of intestinal presentations of myeloid sarcomas. The epitheliotropism, enteropathy-like features and associated clinical presentation with gastrointestinal symptoms mimicked T cell lymphomas. This unique case highlighted the pivotal role of flow cytometry as well as clinicopathological correlation in making a diagnosis of myeloid sarcoma with MPAL phenotype.

Keywords: myeloid sarcoma, epitheliotropism

Back To Top

 

P943 Rare case of infective endocarditis involving mitral annular calcification leading to hemopericardium and sudden cardiac death: A case report

Shauna Wentzella, Vidhya Naira,b.

aMcMaster University, McMaster University Medical Centre, 1200 Main St. West, Hamilton, ON.
bHamilton Health Sciences, Hamilton General Hospital, 237 Barton St. East, Hamilton, ON.

We present a unique case of a 76-year-old female who had sudden cardiac death due to hemopericardium. Post mortem examination revealed infective endocarditis(IE) superimposing on mitral annulus calcification(MAC) leading to abscess formation, epicardial fistulation and hemopericardium. MAC is currently considered a relatively benign condition of the elderly1, however evidence suggests there are severe consequences when these patients develop IE. With an aging population, this is likely to be a more frequent occurrence and should be considered in patients who present with bacteremia of unknown origin.

Back To Top

 

P944 Yolk sac tumor of the colon

Sejal S. Shah, Vishal S. Chandan.

Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.

Objective: Extragonadal germ cell tumors are uncommon. We present the clinicopathologic features of a rare yolk sac tumor of the colon.

Method: A 20-year old woman with known history of ulcerative colitis presented with acute abdominal pain. Imaging showed a 9-cm mass involving the region of cecum. No other abnormality was seen on imaging and the ovaries as well as the uterus appeared unremarkable. She underwent a right hemicolectomy.

Data and Results: The sections from the mass centered in the cecum showed a cellular neoplasm with clear cytoplasm involving the entire colonic wall from the mucosa to the serosa. Admixtures of histologic patterns were seen represented by microcystic/reticular, pseudoglandular and solid patterns. Rare Schiller-Duval bodies were also present. Immunostains were performed and the tumor cells were positive for keratin AE1/AE3, SALL-4, alpha-fetoprotein, CD117, Glypican-3, and CDX2. Arginase-1 and PAX-8 stains were negative. BRG-1, INI-1 and the immunostains for mismatch repair enzymes were intact within the tumor cells. The overall morphology and the results of the stains support a diagnosis of yolk sac tumor. Additional clinical workup excluded the possibility of a metastasis and hence a diagnosis of primary yolk sac tumor of the colon was made.

Conclusions: Extragonadal yolk sac tumor of the colon is extremely rare. Hence it is often not considered in the differential. The histologic variability of yolk sac tumor and its tendency to mimic somatic tumors pose diagnostic challenges. Its accurate diagnosis is essential for prognosis and appropriate clinical management.

Keywords: Yolk sac tumor, colon, SALL-4

Back To Top

 

P945 Histological detection of cytomegalovirus infection in a cervical specimen: Case report, literature review, and clinical correlates

Homan Miraliakbariaa, Shawna Noya.

aDepartment of Pathology, University of Manitoba, Winnipeg, MB.

Cytomegalovirus (CMV) infects between 50 to 85% of the world¬wide population by early adulthood. The virus commonly affects young women between 19 to 30 years, resulting in an asymptomatic infection. However, infection in pregnant women carries certain risks including early spontaneous abortion and fetal infection with potential congenital abnormalities. Although CMV has not been identified as a causative agent in the development of cervical carcinoma thus far, cervical CMV infection has been identified by polymerase chain reaction and culture in women diagnosed with varying degrees of cervical dysplasia, as well as invasive cervical carcinoma. Histologically diagnosed CMV infection of the cervix, however, is quite rare with only few reported cases thus far.

We herein report a case of histologically diagnosed cervical CMV infection in a 24-year old woman. The patient has a history of urinary tract infection and bacterial vaginosis. Following two consecutive pap smears and a cervical biopsy showing a high-grade squamous intraepithelial lesion, she underwent loop electrocautery excision. Microscopic examination showed a completely excised high-grade squamous intraepithelial lesion with background active inflammation. Few scattered large cells with inclusions were identified within the cytoplasm of endocervical glandular epithelial cells. These inclusions subsequently stained positively with anti-CMV antibody. The histological features described in our case, in addition to other features reported in the literature such as lymphoid follicles and fibrin thrombi within small vessels, should alert the pathologist to the possibility of cervical CMV infection. Detection is particularly important in women who may be immunocompromised or planning a future pregnancy.

Keywords: Cervix, cervical dysplasia, cytomegalovirus infection

Back To Top

 

P946 Lymphocytic gastritis induced by pembrolizumab in a patient with metastatic melanoma – a case report

Raymond H. L. Yipa,b, Lawrence H. Leea, David F. Schaeffera, Basil A. Horsta,b, Hui-Min Yanga,b.

aDivision of Anatomic Pathology, Vancouver General Hospital, Vancouver, BC.
bThe University of British Columbia, 317-2194 Health Sciences Mall, Vancouver, BC.

Pembrolizumab is a novel immune checkpoint inhibitor that has been shown to be effective in treating metastatic malignancies such as advanced melanoma. Its therapeutic blockade of programmed cell death-protein 1 (PD-1) allows for re-activation of T cell activity that is effective in targeting cancer cells, however, at the expense of increased autoimmunity.

We describe the first case of lymphocytic gastritis occurring in the setting of pembrolizumab therapy. A 44-year-old man with advanced melanoma and recurrent lung metastases treated with pembrolizumab developed symptoms of dyspepsia and gastroesophageal reflux (GERD) after one month of therapy. Gastric biopsy showed histologic features consistent with lymphocytic gastritis, which was absent on the biopsy two months prior to the start of anti-PD-1 therapy.

Immune-related adverse effects on multiple organs from PD-1 inhibitor therapy have been described, such as colitis, skin rash and hypothyroidism. Lymphocytic infiltrates likely secondary to increased autoimmunity after use of immunotherapy have been observed in the colon, however, such histologic findings in the upper gastrointestinal tract have yet to be described in the literature. Here, we present a case of lymphocytic gastritis in a patient treated with pembrolizumab, suggesting a new manifestation of toxicity.

Keywords: Gastritis, Pembrolizumab, Melanoma, Lymphocytosis, Programmed Cell Death 1 Receptor

Back To Top

 

P947 Identification of Unique Gene Expression Profiles in Usual Interstitial Pneumonia and Non-specific Interstitial Pneumonia

Matthew J. Cecchinia, Karishma Hoseinb, Christopher J. Howletta, Mariamma Josepha, Marco Murab,c.

aDepartment of Pathology and Laboratory Medicine, Western University, London.
bDivision of Respirology, Western University, London.
cToronto Lung Transplant Program, University of Toronto, Toronto.

Background: Usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP) are common forms of interstitial lung disease (ILD). Recent studies have identified potential links between UIP and senescence which is a form of irreversible cell cycle arrest that can be caused by DNA damage, shortened telomeres or oncogene activation. Senescent fibroblasts express p16 and can develop a senescence-associated secretory phenotype (SASP) to produce profibrotic growth factors and matrix remodeling proteins.

Design: Gene expression from explanted lungs of patients with IPF (n=22), NSIP (n=10), mixed IPF-NSIP (n=5), and normal controls (n=11) was assessed. Immunohistochemistry for p16, p53, Periostin and IDO1 was performed on surgical lung biopsies from 22 UIP, 9 NSIP and 5 mixed cases.

Results: UIP cases showed a unique expression pattern with an increased expression of ACTA-2, MUC5B and IGFBP-5 compared to the NSIP cases. Immunohistochemistry identified p16 positive fibroblastic foci in 15 of 23 (65%) of UIP cases, 0 of 9 (0%) NSIP cases and 2 of 5 (40%) mixed cases. P16 fibroblastic foci were also positive for p53 by immunohistochemistry. No difference in Periostin or IDO1 was identified by immunohistochemistry.

Conclusion: UIP cases expressed a distinct subset of growth factors and matrix remodeling genes. P16 positive fibroblastic foci were identified in the majority of UIP cases and highlights a potential important etiological basis for senescence in UIP and supports the ongoing development of senolytic therapies to disrupt this process. Further, there is a potential use for p16 as an adjunct marker to distinguish UIP from NSIP.

Keywords: UIP, NSIP, senesence, p16

Back To Top

 

P948 A case of Intravascular Large B-Cell lymphoma found on autopsy

Shao Shi Li1, Edward Tweedie1, Chris Howlett1.

1Department of Pathology and Laboratory Medicine, Western University.

A 75 year old women presented to Emergency Department in August, 2017 after one year history of increased leg swelling, difficult mobilization, as well as pain and numbness. The etiology of her bilateral leg swelling was unclear. Previous bone marrow biopsy to rule out multiple myeloma as well as amyloidosis, was negative. Skin biopsy was negative for vasculitis and panniculitis. Echocardiogram of heart was normal. CT chest, abdomen, and pelvis did not show any evidence of malignancy. After admission, her renal function worsened, and there was an increase in her white blood cell count. She died days later.

Microscopic examination from autopsy revealed a diagnosis of intravascular large B-cell Lymphoma, diffusely involving multiple organs including heart, lungs, skin, pancreas, liver, thyroid, peri-adrenal fat, bladder, kidneys, thyroid, and pituitary. This multi-organ involvement accounts for the variety of signs and symptoms, including the skin changes. No lymphadenopathy was identified and the bone marrow did not appear to be involved by this malignancy.

Intravascular diffuse large B-cell lymphoma is a rare extra-nodal lymphoma where growth is restricted to the lumina of vessels, particularly capillaries. The cells are large, with 1 or more prominent nucleoli, scant cytoplasm, and frequent mitotic figures. Its estimated frequency is estimated at <1 per 1 million persons. Reference: Orwat DE, Batalis NI. Intravascular Barge B-cell Lymphoma. Arch Pathol Lab Med. 2012; 136: 333-338.

Keywords: intravascular large b-cell lymphoma, extra-nodal lymphoma, autopsy

Back To Top

 

P949 10 Tips for implementing an integrated standardized provincial electronic pathology synoptic reporting program

Brigette Rabela, James Cupplesb, Nick van der Westhuizenc.

aProvincial Health Services Authority, Vancouver, BC.
bDepartment of Pathology, Royal Columbian Hospital, New Westminster, BC.
cDepartment of Pathology, Royal Jubilee Hospital, Victoria, BC.

Objective: As pathology reporting becomes increasingly complex, the need for complete, clear reports becomes increasingly important. Synoptic Reporting software for cancer checklists creates a standardized pathology report that guarantees all mandatory fields are included.

Methods: Detailed project plan and guaranteed funding from the Canadian Partnership Against Cancer (CPAC).

Data and Results: British Columbia successfully implemented mTuitive’s xPert Synoptic Reporting Software in 23 pathology sites across 7 health authorities based on the following 10 essential elements:

  1. Project Manager
  2. Single Synoptic Reporting Tool interfacing with all Lab Information systems in the province
  3. Central Data Repository to collect discrete pathology data elements and corresponding patient data from all Laboratory Information systems
  4. Provincial Coordinator for single point of contact for pathologists, vendors and Laboratory Information teams
  5. Advisory Committee for quality, standardization and adoption
  6. Checklist Champions for checklist content
  7. Comparative Feedback Reports to pathologists
  8. Knowledge Mobilization and Change Management strategies
  9. Quarterly Newsletters giving updates on the status of the Synoptic Reporting Project
  10. CAP Electronic Cancer Checklists (eCC’s) as the standard for British Columbia’s checklists and making as few changes to these as possible. Changes are vetted by the Synoptic Reporting Advisory Committee and/or the checklist Champion, with reference to the province’s own Synoptic Reporting Standards document.

Conclusions: British Columbia’s unique approach to implementing Electronic Synoptic Reporting allowed for standardization across the province in an effective and efficient manner. From this experience, the team in British Columbia compiled 10 tips for implementing an integrated Electronic Synoptic Reporting solution.

Back To Top

 

P950 Methimazole-associated severe systemic p-ANCA vasculitis – a case report

Sean Hacking1, Marina Ionescu1, Vanesa Bijol1.

1Department of Pathology, Long Island Jewish Medical Center, Lake Success, NY.

Introduction: Anti-neutrophil cytoplasm antibodies (ANCA) of myeloperoxidase (MPO) specificity by ELISA show perinuclear distribution on indirect immunofluorescence (p-ANCA) and are often associated with renal-limited disease with crescentic glomerulonephritis. ANCAs are usually idiopathic but can be drug-associated. Here we describe an unusually aggressive course of systemic vasculitis mediated by p-ANCA in a patient with methimazole exposure.

Clinical Presentation: A 64-year-old female with a history of hyperthyroidism treated with methimazole, presented to hospital with upper abdominal pain. Subsequently the patient was diagnosed with systemic p-ANCA vasculitis. Her serologic work up revealed positive anti-nuclear antibody (ANA) and p-ANCA, with positive anti-MPO. Three weeks following admission the patient underwent a change in mental status and was found to be pulseless; she was pronounced dead and an autopsy was performed.

Pathology Findings: At autopsy microscopic review, severe multifocal transmural necrotizing vasculitis was seen in the kidney and posterior epicardial left ventricular wall. Diffuse hemorrhage was found in the lungs. The kidneys also revealed necrotizing and crescentic glomerulonephritis.

Conclusions: Severe necrotizing arteritis with crescentic glomerulonephritis suggests a severe form of ANCA-related disease. Such severe presentation is unusual for p-ANCA related disease and has not been reported in association with methimazole use. Awareness of this uncommon adverse reaction is of paramount importance for early recognition and treatment to prevent disease progression and death.

Back To Top

 

P951 Cytologic-histologic correlation of pancreatic masses: Our experience with SharkCore™ needle biopsy versus endoscopic ultrasound-guided fine needle aspiration biopsy

Alexandra Pettita, Ashley Stuecka, Tom Arnasona, Geoff Williamsb, Emily Filtera.

aDepartment of Pathology, Dalhousie University, Halifax, NS.
bDivision of Digestive Care and Endoscopy, Department of Medicine, Dalhousie University, Halifax, NS.

Introduction: The majority of pancreatic cancers are ductal adenocarcinoma, frequently presenting at high stage. Endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNAB) is a minimally invasive method of diagnosing unresectable pancreatic cancer. The sensitivity of pancreatic EUS-FNAB is variable. The novel SharkCore™ needle obtains a small core biopsy of tissue for histologic evaluation and has been shown to increase sensitivity over conventional pancreatic EUS-FNAB cytology. The goal of this study was to compare diagnostic adequacy using both EUS-FNAB and SharkCore™ biopsy approaches for pancreatic lesions.

Methods: All pancreatic masses evaluated with both a SharkCore™ tissue biopsy and EUS-FNAB performed at the same time over a one-year period were retrospectively reviewed, and diagnoses were recorded and correlated. Technical and/or interpretive issues that may have had an impact on the final diagnosis were identified.

Data and Results: A total of 25 pancreatic masses were evaluated using both a SharkCore™ and EUS-FNAB sampling approach. The SharkCore™ biopsy method more frequently provided a definitive diagnosis of adenocarcinoma (56% vs. 36%), and when both methods were used together 72% of cases were diagnosed as suspicious or positive for adenocarcinoma. Thirty-two percent of the SharkCore™ biopsies were reported as non-diagnostic and contained mainly clotted blood only, although this result became less frequent over the course of the study.

Conclusions: The SharkCore™, particularly with increasing operator experience, may outperform EUS-FNAB alone, but the two methods used in tandem provide the highest diagnostic yield.

Keywords: Cytology, Pancreatic cytology, Pancreatic cancer, SharkCore biopsy, Fine needle aspiration

Back To Top

 

P952 Significant risk factors for the development of hyponatremia on citalopram treatment

Andrea C. Shysha,b, Zahinoor Ismailc, Davinder Sidhua,b, Markus Vaskad, Maggie Guob, Christopher Nauglera,b,e.

aDepartment of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB.
bCalgary Laboratory Services, Calgary, AB.
cHotchkiss Brain Institute, University of Calgary, Calgary, AB.
dKnowledge Resource Service, Alberta Health Services, Calgary, AB.
eDepartment of Family Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB.

Introduction: Hyponatremia is a common and under-recognized side effect of selective serotonin reuptake inhibitors (SSRI). Despite its clinical importance, there are few large-scale studies on the risk factors associated with this adverse reaction. This study aims to identify risk factors for hyponatremia in a large, population-based cohort with new prescriptions for citalopram.

Methods: Following approval from ethics review board, data was obtained from an Alberta Health Pharmacy database to identify new citalopram prescriptions from 2010-2017, inclusive. Patients with new prescriptions were linked with Calgary Laboratory Services data to identify patients who developed hyponatremia following prescription initiation. Hyponatremia was defined as serum sodium level <135 mmol/L. Associations were determined by performing binary logistic regression with the development of hyponatremia as the dependent variable.

Results: A total of 18,441 patients with new prescriptions were identified; 12,041 females and 6,400 males. The mean age was 54.6 years old with a standard deviation of 21 years. 2,364 (12.8%) of these patients developed hyponatremia, 1432 (11.8% of) females and 932 (14.5% of) males. Multivariate regression showed significant associations of hyponatremia with lower baseline sodium (OR = 1.24), age above 65 (OR = 3.2), and male sex (OR = 1.2). Certain Drug Identification Numbers were also significantly associated with increased or decreased serum sodium levels.

Conclusion: This is the first large-scale, population-based study to explore risk factors for development of hyponatremia in patients starting on SSRI’s. Significant new findings are a higher overall rate of hyponatremia than previously reported and a higher incidence in males.

Keywords: Risk factor, hyponatremia, citalopram

Back To Top

 

P953 Utility of IDH1R132H immunohistochemistry in diagnosis of metastatic anaplastic oligodendroglioma – a case report

M. Kharaa, C.M. Davidson a, J.P. Rossiter a.

aDepartment of Pathology and Molecular Medicine, Queen’s University, Kingston, ON.

Oligodendroglioma is a diffuse glioma (WHO grade II) that has distinctive histology and is characterized genetically by co-deletion of chromosomal arms 1p and 19q, and IDH1/2 gene mutation, in > 90% IDH1R132H, reliably detected by immunohistochemical staining (IHC) with IDH1R132H mutation-specific antibody. Although uncommon, extra-neural metastasis, particularly to bone marrow and lymph nodes, is a recognized complication, especially for anaplastic oligodendroglioma (WHO grade III). This is the case of a 59-year-old man who initially presented with increasing headache and left upper limb weakness and MRI evidence of a large solid and cystic left frontal tumour with regional enhancement. He underwent subtotal surgical resection of this lesion. Pathological evaluation showed oligodendroglioma, WHO Grade II, IDH1R132H immuno-positive, and 1p/19 co-deleted by FISH. By eight months postoperatively there was neuroimaging evidence of local tumour recurrence and he received chemo(temozolomide)radiation therapy. Within one year of treatment completion he presented with pancytopenia, imaging findings suspicious for widespread metastatic bone disease and a 3 cm mass in the left adrenal gland. A core needle biopsy of the adrenal mass showed a poorly differentiated neoplasm with Ki67 proliferative index ~ 80%. Sequential panels of IHC showed the tumour to be negative for a variety of markers, including CK-pan, CD45, MART1 and PSA. The tumour was S100 immunoreactive and a few cells were GFAP-positive. Decisively, the tumour cells were strongly IDH1R132H immuno-positive, establishing a diagnosis of metastatic anaplastic oligodendroglioma. This case highlights the diagnostic utility of IDH1R132H IHC in patients with oligodendroglioma and suspected metastatic disease.

Back To Top

 

P954 Living in a virtual reality – a cross-over study comparing resident examination performance with traditional and virtual microscopy

Alicia R. Andrewsa, Nick Baniaka, Catalin Taraboantab, Amy Bromleyc, Tyler Hickeyb, Marilyn Kinlocha.

aDepartment of Pathology and Laboratory Medicine, University of Saskatchewan, Saskatoon, SK.
bDepartment of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC.
cDepartment of Pathology and Laboratory Medicine, University of Calgary, Calgary, AB.

Introduction: Digital images (static images and virtual microscopy) are becoming commonplace in resident evaluation. The Royal College of Physicians and Surgeons of Canada changed their pathology examinations to an all-digital format in 2017, and many residency programs utilize digital images for internal examinations. The skills for evaluating virtual and glass slides are different, and concerns have been raised as to whether virtual microscopy-based examinations yield representative evaluations of residents. We hypothesize that there is no difference in resident performance between the two modalities, given that overall their similarities outweigh their differences.

Objective: To compare resident performance in traditional versus virtual microscopy examinations.

Methods: Residents from all post-graduate years, at three Canadian pathology residency programs, participated in this cross-over study. Sites were assigned to either traditional or virtual microscopy for the first of two slide examinations (25 slides, two minutes per slide). For the second sitting, the examination modalities were reversed. The data from each sitting were analysed by Wilcoxon Two-Sample Test, using SAS 9.4.

Data and Results: Twenty-nine residents sat the first examination: 11 virtual (mean score 9.5/25, SD 4.3) and 18 traditional (mean score 11.8/25, SD 6.0), p = 0.38. Twenty-eight residents sat the second examination: 16 virtual (mean score 11.1/24, SD 4.9) and 12 traditional (mean score 12.2/24, SD 4.9), p = 0.40. All score distributions were non-Gaussian.

Conclusions: Our study shows no statistical difference in resident performance when examined using glass slides or virtual microscopy. This finding supports the use of digital images for resident evaluation.

Keywords: Resident education, virtual microscopy, digital microscopy

Back To Top

 

P955 Isolated tumor cells in sentinel lymph nodes for primary breast cancer: A cohort analysis

Manolhas A. Karkadaa, Ryan C. DeCostea,b, Penny J. Barnesa,b, Daniel Raysonc, Gillian C. Bethunea,b.

aaDepartment of Pathology, Dalhousie University.
bDepartment of Pathology & Laboratory Medicine, Division of Anatomical Pathology, Nova Scotia Health Authority.
cDepartment of Medicine, Division of Medical Oncology, Nova Scotia Health Authority, Halifax, NS.

Introduction and Objective: Sentinel lymph node biopsy (SLNB) is a key component of breast cancer staging. Historically, many institutions performed cytokeratin immunohistochemistry (CK-IHC) on every SLNB to help detect isolated tumour cells (ITCs). This practice was discontinued at our institution in 2013 after guidelines suggested limited clinical utility. We aimed to determine the resultant impact on the rate of ITC detection.

Methods: Upon Research Ethics Board approval, pathology reports were reviewed from 250 consecutive invasive breast cancer cases with SLNBs resected in 2010 and 2015. Data abstracted included: tumor type, CK-IHCs ordered, nodal status and presence of ITCs. Cases with ITCs in 2015 were re-reviewed by a breast pathologist. Data were analyzed using Fisher’s exact test.

Data and Results: In 2010, all cases utilized CK-IHC vs. 57 cases in 2015 (P<0.001). There were 22 cases with ITCs in 2010 vs. 11 in 2015 (P=0.07). 20 cases contained ITCs without additional metastases in 2010 vs. 9 in 2015 (P=0.054). Excluding lobular carcinomas, for which CK-IHC is ordered reflexively at our institution, there were 18 cases with ITCs in 2010 vs. 7 in 2015 (P=0.038). In 2015, CK-IHC was ordered in 10 of 11 cases containing ITCs: 4 were lobular carcinomas, 3 had lymphovascular invasion, and 3 had CK-IHCs ordered to confirm an H&E suspicion of ITCs.

Conclusion: Excluding lobular histology, a significant decrease in the reported ITC rate is observed since discontinuation of reflex CK-IHC testing. The cost impact and clinical significance of decreased ITC detection is being further investigated.

Keywords: Breast cancer, Sentinel lymph node biopsy, Isolated tumour cells

Back To Top

 

P956 Integrated proteomic and peptidomic analysis to identify biomarkers of aggressive behaviour in early-stage renal cell carcinoma

Ashley Di Meoa,b,c, Ihor Batruchc, Marshall Brownc, Michael A.S. Jewettd, Antonio Finellid, Eleftherios P. Diamandisb,c, George M. Yousefa,b.

aThe Li Ka Shing Knowledge Institute of St. Michael’s Hospital, Toronto, ON.
bDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.
cThe Advanced Centre for Detection of Cancer at the Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, ON.
dDivision of Urologic Oncology, Princess Margaret Cancer Centre, Toronto, ON.

Objective: To determine whether an integrated proteomic and peptidomic signature could accurately distinguish between progressive and non-progressive clear cell renal cell carcinoma small renal masses (ccRCC-SRMs).

Methods: We performed an integrated urinary proteomic and peptidomic analysis in patients with progressive and non-progressive clear cell RCC-SRMs. We analyzed protein and peptide fractions separately on the Q-Exactive mass spectrometer. We performed survival analysis and protease prediction analysis. Overall survival data were obtained from The Cancer Genome Atlas (TCGA).

Data and Results: A total of 2,589 unique proteins were identified by proteomic analysis. In addition, peptidomic analysis identified a total of 20,760 unique endogenous peptides arising from 1,418 proteins. We identified twelve candidate proteins that could significantly differentiate progressive from non-progressive clear cell RCC-SRMs. Charged multivesicular body protein 2a (CHMP2A, AUC: 0.97), Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1, AUC: 0.88), Integral membrane protein 2B (ITM2B, AUC:0.88), and ferritin light chain (FTL, AUC: 77) expression was significantly elevated in progressive versus non-progressive clear cell RCC-SRMs. Moreover, CHMP2A (p=0.02) and FTL (p=0.001) expression significantly correlated with overall survival. We identified sixty-four endogenous peptide candidate that were significantly elevated in progressive versus non-progressive clear cell RCC-SRMs. Protease prediction analysis identified several proteases predicted to be dysregulated in aggressive SRMs, including CTSS, MEP1A, MME, CMA1, CTSL, HTRA2, CTSE, and CTSB.

Conclusions: Taken together, elevated proteomic and peptidomic urinary levels represent potential prognostic biomarkers for progressive and non-progressive renal lesions.

Keywords: mass spectrometry, proteomics, peptidomics, small renal mass, renal cell carcinoma

Back To Top

 

P957 Detection of neutral lipids in formalin-fixed, sucrose-impregnated tissue using the Oil Red O stain

Linnea Dukea, Chantal Bernarda, Steffen Albrechta, Jason Karamchandania.

aDepartment of Pathology, McGill University, Montreal, Quebec.

Objective: Assessment of hepatocytic neutral lipid in pediatric metabolic autopsies is usually done using an Oil Red O stain (OROS) on frozen sections (FS) of OCT-embedded fresh-frozen tissue. This may prolong the autopsy and samples must be stored in a low-temperature freezer. Our objective was to validate an alternative OROS method for use with formalin-fixed (FF) tissues.

Methods: FF tissue was used for FS after overnight impregnation in a 30% (w/v) aqueous sucrose solution. FF liver samples from 4 cases previously assessed with OROS on fresh-frozen tissue were re-assessed using this method.

Results: The modified OROS method yielded identical results (2 positive, 2 negative). The method also detected fat and bone marrow emboli in FF lung tissue and works on FF white matter in leukodystrophy cases. Histological quality of the sections was similar to permanent sections of formalin-fixed paraffin embedded tissue, in contrast to FS on fresh-frozen tissue. Sample impregnation and staining were easily batched for greater efficiency. Figure 1 illustrates the improved histology obtained using the modified technique.

– click here for figure

Conclusions: OROS on FS of FF-sucrose impregnated tissue is a simpler and economical alternative to OROS on fresh-frozen samples and allows the stain to be applied to a greater variety of tissues.

Keywords: Oil Red O stain; sucrose impregnation; frozen section; formalin fixed tissue

Back To Top

 

P958 Matrix rigidity governs cell morphology and sunitinib response in renal cell carcinoma

Zsuzsanna Lichnera, Luca Lichnera, Fallou Wadea, Rola Saleeba, Qiang Dinga, Fabio Rotondoa, Stephen Michaela, Darren A Yuena,b, Andras Kapusa, George M. Yousefa,b.

aKeenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute.
bSt. Michael’s Hospital, Toronto, Ontario.

Objectives: of the study was to examine RCC morphology as a function of substrate rigidity and to determine whether the RCC growth modalities augmented by the different matrixes influence their treatment response.

Methods: RCC cell lines were cultured on control stiff (plastic, glass) and soft (matrigel surfaces) surfaces and on engineered matrixes with 2kPa, 5kPa (soft), 30kPa and 100kPa (stiff) rigidities. Animal experiments were approved by the ACC. Flow cytometry, metabolic cell proliferation assay, Ki67 and Caspase-3 staining were used to assess mitosis and apoptosis. Gömöri trichome, HPS and MSB visualized EMC components. Aperion software was used to quantify IHC positivity.

Results: In vitro, RCC cell lines preferentially formed tumor spheroids on low rigidity substrates opposed to the adherent monolayer that was the predominant growth modality on stiff surfaces. Sunitinib treatment had high toxicity on RCC that were cultured on stiff substrate, while the spheroids (promoted by soft matrix) showed increased resistance. In vivo, tumor areas with less ECM accumulation (soft matrix) formed epithelioid nests, and exhibited high positivity for Ki67 with minimal Caspase-3 positivity. On the contrary, tumor areas in the proximity of ECM deposits were spindled and exhibited low positivity for Ki67 and were highly positive for Caspase-3.

Conclusions: Matrix stiffness influences RCC growth dimensionality in vitro and in vivo. Mechanosensing-directed morphological change is an important contributor to treatment response. Interference with mechanosensor pathways should be explored to sensitize RCC cells for sunitinib.

Keywords: renal cell carcinoma, sunitinib response, matrix rigidity, cell morphology

Back To Top

 

P959 Frequency of breast carcinoma HER2 discordance between biopsy-excision pairs at a multi-hospital regional laboratory

Mario Capitanoa, Susan Robertsona.

aDepartment of Pathology and Laboratory Medicine, The Ottawa Hospital, General Campus, Ottawa, Ontario.

Introduction: Current practice at our regional laboratory is to retest all cases of breast carcinoma for human epidermal growth factor receptor 2 (HER2) amplification on the excision specimen if the biopsy was negative since the 2013 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) HER2 testing breast cancer guidelines may not be safe for a regional laboratory where there is specimen processing and tumour grading variability.

Methods: All breast carcinomas that had testing for HER2 amplification on the biopsy and excision specimen at any hospital site over a 9 month period were assessed for discordance between the biopsy-excision pairs. HER2 testing was performed using immunohistochemistry and dual probe fluorescent in situ hybridization (FISH) in accordance with FDA kit protocols at the central laboratory site and read by a breast pathologist.

Results: Two hundred seventy-eight cases of HER2 biopsy-excision pairs were identified (grade 1= 64 cases, grade 2=140 cases, grade 3=74 cases). One case was amplified at excision for a 99.6% concordance rate. This discordant case was a grade 3 carcinoma that was HER2 equivocal by FISH on biopsy and HER2 positive by FISH on excision.

Conclusions: This series showed a high concordance rate for HER2 between biopsy-excision breast carcinoma pairs in a regional laboratory setting. Based on this data, it could be considered safe to not retest excision specimens that were HER2 negative on biopsy unless otherwise indicated. These results have cost and workload implications and will be interpreted in conjunction with the updated 2017 ASCO/CAP HER2 testing guidelines.

Keywords: breast carcinoma, HER2, biomarkers

Back To Top

 

P960 A case presentation of concurrent lung adenocarcinoma and blastomycosis infection

L. David Sellena, Miao (Vivian) Lua.

aDepartment of Pathology, University of Manitoba and Diagnostic Services of Manitoba, Health Sciences Center. Winnipeg, MB.

Objective: To present a rare case of concurrent adenocarcinoma and blastomycosis infection diagnosed on core biopsy of a left lower lobe lung mass.

Methods: Case report.

Results: The patient is a 73 year old male from northwestern Ontario who presented with hemoptysis and was found to have a left lower lobe mass on CT. A core needle biopsy was performed and the microscopic examination showed necrotizing granulomata with numerous organisms with broad based budding consistent with blastomycosis. In the background were clusters of atypical epithelial cells with rare glandular formation. The cells stained positive for TTF-1 and Napsin-A supporting a diagnosis of adenocarcinoma of lung primary.

Conclusions: Blastomycosis is an infection caused by the fungal organism blastomyces dermatitidis which is endemic to North America particularly in the wooded areas North West of the great lakes. It can infect the lungs of humans and often causes a neutrophilic or granulomatous mass forming lesion. A common differential diagnosis for patients with a solitary lung mass in this geographical region includes blastomycosis and lung carcinoma. However, a patient presenting with concurrent infection and carcinoma is rare. In this case the patient had concurrent infection and adenocarcinoma both of which were identified on core biopsy.

Keywords: blastomycosis, lung adenocarcinoma

Back To Top

 

P961 Clear Cell Renal Cell Carcinoma: Tumors with Invasion into the Sinus Fat, Perinephric Fat, and Renal Vein are Associated with Increased Cancer Specific Mortality

Kevin Hogana, Nicola Schiedaa,b, Eric Belangera,b, Trevor A. Flooda,b.

aUniversity of Ottawa, Ottawa, ON.
bThe Ottawa Hospital, Ottawa, ON.

Objective: The purpose of this study was to determine if different patterns of invasion that define pT3a disease [sinus fat invasion (SFI), perinephric fat invasion (PFI) and renal vein invasion (RVI)], in addition to other prognostic features, were associated with metastases or cancer specific mortality (CSM) in patients with clear cell renal cell carcinoma (CCRCC).

Methods: A search between January 2011 and December 2015 for pT3a CCRCC on radical nephrectomy identified 97 patients. Potential prognostic features were retrieved from reports and included: SFI/ PFI/RVI, patient age, tumor size, Fuhrman nuclear grade (FNG), margin status, tumor necrosis, and sarcomatoid differentiation. Univariate analyses and multivariate analyses were performed. Kaplan Meier curves and Cox hazard proportional ratios were calculated for variables that were associated with CSM.

Results: At univariate analysis, size, FNG, PFI, margin involvement, necrosis, and sarcomatoid differentiation were significantly associated with metastases (p<0.05). Size, FNG, PFI, necrosis, and sarcomatoid differentiation were also significantly associated with CSM (p<0.05). The presence of more than one pattern of invasion and sarcomatoid differentiation were most strongly associated with metastases and CSM (p<0.0001). At multivariate analysis, only these features were associated with CSM (p<0.05). Kaplan Meier curves showed significant differences in CSM when sarcomatoid differentiation was present (Figure 1, p<0.0001) and were signficantly worse as the number of patterns of invasion increased (Figure 2, p<0.0001).

– click here for figure

Conclusion: The presence of all three patterns of invasion and sarcomatoid differentiation imparts a worse cancer specific survival in patients with CCRCC. Our study suggests that not all pT3a tumors behave in a similar manner.

Back To Top

 

P962 Rare transformation of Ovarian Low-grade Serous Carcinoma to High-Grade Carcinoma: A Report of 3 Cases

Angela S. Chenga, C. Blake Gilksa,b, Lynn N. Hoangb.

aGenetic Pathologic Evaluation Center, Vancouver, BC.
bDepartment of Anatomical Pathology, Vancouver General Hospital and University of British Columbia, Vancouver, BC.

Background: Ovarian low-grade serous carcinomas (LGSCs) exhibit more indolent behavior than high-grade serous carcinoma and are typified by recurrent disease. The vast majority of LGSC do not bear TP53 mutations; BRAF (V600E) mutations have been associated with better prognosis. Transformation of LGSC to high-grade carcinoma is exceedingly rare (with only 6 cases reported to date) and the molecular events which lead to such transformation are unknown. Our objective was to assess p53, BRAF and WT1 immunohistochemistry in 3 cases of LGSC with transformation to high-grade carcinoma in order to better understand the molecular events underlying this rare phenomenon.

Methods: We identified 3 cases where LGSC transformed to a high-grade component. H&E slides were reviewed and immunohistochemistry was performed. p53 was scored as 0=null, 1=wild-type, 2=overexpressed. BRAF and WT1 was scored as positive or negative.

Results:

Table 1: Summary of clinical, pathologic and immunohistochemical (IHC) features of 3 cases of low-grade serous carcinoma (LGSC) with transformation to high-grade carcinoma.

Case

Age

FIGO Stage

Clinical Features, Treatment and Follow-Up

Pathology

IHC

P53

WT1

BRAF

A

46

IIIC

• Presented with abdominal pain and left breast mass

• Biopsy of the pelvic mass showed LGSC and biopsy of the breast showed invasive ductal carcinoma with a positive axillary lymph node

• Received chemotherapy, ongoing

• No follow-up available

• HG carcinoma arising from LGSC, involving and confined to one ovary

• SBT of opposite ovary

• Mixed invasive and non-invasive implants in peritoneum and omentum

LG

1

POS

NEG

HG

1

POS

NEG

B

44

IIIA

• Presented with cognitive dysfunction and found to have adnexal mass incidentally

• Prior history childhood acute lymphoblastic leukemia (ALL) and aneurysmal bone cyst (ABC)

• Remote chemotherapy and radiation for ALL and ABC during childhood

• NED; 8 months

• HG carcinoma arising from LGSC, involving and confined to one ovary

• SBT of opposite ovary

• Single non-invasive implant in omentum

LG

1

POS

NEG

HG

0

POS

NEG

C

69

II

• Presented with urinary retention

• Found to have a large pelvic mass

• Received chemotherapy

• Recurred at 9 months; received radiation therapy

• DOD; 13 months

• Carcinosarcoma (homologous) arising from LGSC/SBT in one ovary

• Non-invasive implant on uterine serosa

LG

1

POS

NEG

MMMT

2

POS*

NEG

*Negative in the sarcoma component and positive in the associated carcinoma component

Conclusions: Transformation from LGSCs to high grade carcinoma is rare, with only 3 cases occurring over a 20 year span. Acquisition of abnormal p53 was observed in 2 of 3 cases. No cases displayed abnormal BRAF. In all cases, WT1 was positive in the low-grade and high-grade areas supporting their common origin. DNA sequencing is currently being performed and the results are to follow.

Keywords: ovarian cancer; low-grade serous carcinoma; transformation

Back To Top

 

P963 Fire and the phoenix: George Adami’s pathology textbooks and the McGill Medical Museum

L. Richera, R. Frasera,b.

aDepartment of Pathology, McGill University, Montreal, QC.
bMaude Abbott Medical Museum, McGill University, Montreal, QC.

Introduction: George Adami came to Montreal from England in 1892 to become the first Professor of Pathology at McGill University and the Chief of Pathology at the Royal Victoria Hospital. One of his major goals was to improve medical student teaching. An important part of this occurred in McGill’s medical museum, to which he hired Maude Abbott as Director in 1898. Adami also decided to write one of Canada’s first textbooks of pathology. Many of the gross images he used were of museum specimens mounted in glass jars. After much of his manuscript and illustrations were destroyed by fire in 1907, he had to scramble to find a new source for these.

Method: Adami’s two volume Principles of Pathology (1909) and his abridged Textbook of Pathology for Medical Students (1912) were reviewed and figures were logged and classified. Other pathology textbooks published within 10 years of Adami’s were reviewed for similarities in style and organization.

Data and Results: The Principles of Pathology‘s 94 original gross specimen illustrations were replaced by 71 new photographs. Surprisingly, the abridged version for medical students (with John McCrae) contained almost no photographs of museum specimens and few gross pathology reproductions. In addition to the unusual form of illustration, Adami emphasized the primacy of general over systemic pathology and the importance of pathophysiology in his textbooks.

Conclusions: Adami’s textbooks were critically acclaimed and provide insight into how pathology was perceived and taught in the early 1900s, both at McGill and in North America at large.

Keywords: Adami, pathology education, textbook, history, medical museum

Back To Top

 

P964 Identification of grossing criteria for a safe use of frozen section in the intraoperative evaluation of lung cancer resections

Andréanne Gagnéa, Étienne Racinea, Michèle Oraina, Salma Mezioua, David Joubertb, Serge Simarda, Christian Couturec,f, Sylvain Pagéc, Sylvain Trahanc, Paula Ugaldea,d, Yves Lacassea,e, Philippe Jouberta,c,f.

aResearch Center, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC.
bUniversity of Ottawa, Department of Criminology, Ottawa.
cDepartment of Pathology and Cytology, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC.
dDepartment of Thoracic Surgery, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC.
eDepartment of Pneumology, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, QC.
fLaval University, Molecular biology, Medical Biochemistry and Pathology Department, Quebec City.

Introduction: Due to lack of guidelines, routine use of intra-operative frozen section for the evaluation of surgical margins in lung oncology is a standard in many pathology departments. This costly and time-consuming practice seems unjustified as reported rates of positive margins remain low.

Objective: To evaluate clinicopathological criteria associated with positive margins and establish safe recommendations regarding the use of frozen sections.

Methods: This retrospective cohort included 1903 consecutive patients with a lung resection for a primary or metastatic malignant neoplasm between 2006 and 2015. Clinicopathological data were retrieved from medical files. Univariate and multivariate analyses were used to identify variables associated with a positive surgical margin. ROC curves and a probability table of positive margins based on tumor-margin distance were also made. The results were then confirmed in a validation cohort of 27 patients with positive margins.

Results: The rate of positive margins was 3.79%. A positive margin status changed the surgical management in 48.6% of patients. A small tumor-margin distance was associated with higher risk of positive bronchovascular and parenchymal margins in univariate and multivariate analyses. Selecting a 2.0 cm tumor-margin distance cut-off for realizing a frozen section would result in a reduction of 55.3% of intra-operative frozen evaluations with a risk of missing a positive margin of 0.61%.

Conclusion: We show that systematic use of frozen section for intra-operative evaluation of surgical margins is unnecessary. A better selection of patients with a higher risk of a positive margin can be achieved by using tumor-margin-distance as a simple gross evaluation parameter.

Keywords: Lung cancer, frozen sections, intraoperative evaluation

Back To Top

 

P965 Large 7 cm parathyroid cyst in a 14 year old boy: case report and review of literature

Ellen Caia,d, Paula A. Tellezb,d, Robyn Cairnsc,d, Neil K. Chadhab,d, Anna F. Leea,d.

aDepartment of Pathology and Laboratory Medicine, Children’s and Women’s Health Centre of British Columbia, Vancouver, BC.
bDivision of Pediatric Otolaryngology-Head and Neck Surgery, Children’s and Women’s Health Centre of British Columbia, Vancouver, BC.
cDepartment of Medical Imaging, Children’s and Women’s Health Centre of British Columbia, Vancouver, BC.
dFaculty of Medicine, University of British Columbia, Vancouver, BC.

Introduction:Parathyroid cyst is rare, with fewer than 300 adult cases and only 7 pediatric cases reported. Most are non-functioning but a minority causes hypercalcemia due to parathyroid hormone (PTH) production. The pediatric clinical differential diagnosis includes branchial cleft cyst and cystic degeneration of thyroid. PTH can be found in the cyst aspirate, but tissue biopsy enables definitive diagnosis.

Clinical Presentation: A 14 year old boy had 3-month history of a growing left anterior neck mass, with no associated pain, dyspnea, dysphonia, or apnea. Thyroid function tests were normal. Clinical exam showed a 6 cm cystic lesion at the left lateral border of thyroid gland. Ultrasound and computerized tomography showed a simple cyst in the lateral left thyroid lobe, and right tracheal deviation. The patient declined fine needle aspiration biopsy of the cyst. Left hemithyroidectomy and cyst excision were performed. Intraoperatively, no sinus tract was identified and the left superior parathyroid was not positively identified.

Results: Grossly there was a ~7 cm thin-walled cyst with smooth inner lining. Residual thyroid tissue was present superomedially. The cyst fluid was clear and colourless. Microscopically, lining cells were simple cuboidal to low columnar with clear cytoplasm, positive for GATA3 and negative for TTF-1. Conversely, the adjacent mildly compressed benign thyroid epithelium was positive for TTF-1 and negative for GATA3. These findings allowed for definitive diagnosis of benign parathyroid cyst.

Conclusion: Large parathyroid cyst is very rare. Its presence in children can mimic other pediatric cystic neck lesions. Immunohistochemistry for GATA3 and TTF-1 is useful to identify this very rare entity.

Back To Top

 

P966 A descriptive analysis of “rush” surgical pathology specimens

Christopher Trana, Keith Kwana, Helen C. Ettlera.

aLondon Health Sciences Center.

Introduction: For surgical and cytology specimens, requests for “rush” processing can be made, implying the need for urgent diagnosis. There is a paucity of data on “rush” specimens, and the aim of this study was to better understand the temporal, patient, clinician, and specimen factors surrounding “rush” requests.

Methods: A descriptive statistical analysis was performed on all “rush” requests at the London Health Sciences Center Department of Pathology and Laboratory Medicine between January 1 and December 31, 2016. Temporal-, specimen-, clinician-, and patient-specific variables were collected. Subgroup analyses for specimens with a requested date for diagnosis were performed.

Results: A total of 826 “rush” requests were identified, including 740 (89.6%) surgical specimens, 83 (10.0%) cytology samples and 3 (0.4%) Pap smears. The most common specimen specialties were gastroenterology (31.4%), cytology (10.0%) and gynecology (10.1%). The average turnaround time was 3.36 days (SD = 2.75). At the time of specimen collection, 54.4% of patients were outpatients, and 45.6% were inpatients. Of the “rush” requests, 264 specified a date required for diagnosis, most of which were from outpatients (72.3%). The average turnaround time requested was 4.70 days (SD = 3.44), and 82.5% of the requests were signed out by the specified date.

Conclusions: A significant proportion of “rush” requests may not be necessary for immediate clinical management. Differentiating specimens that require an immediate diagnosis from specimens that require a diagnosis by a specific date may allow more effective triaging of cases. Defining benchmarks for “rush” specimens may help in evaluating the effectiveness in handling time-sensitive cases.

Keywords: surgical pathology, quality assurance

Back To Top

 

P967 Modulating ATP binding cassette (ABC) transporters in papillary renal cell carcinoma type 2 enhances its response to targeted molecular therapies

Rola M Saleeba,b, Mina Faraga, Zsuzsanna Lichnera, Fadi Brimoc, Fabio Rotondoa, Michelle R. Downesa,d, George M Yousefa,b.

aDepartment of Pathology and Laboratory Medicine, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, ON.
bDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON.
cDepartment of Pathology, McGill University Health Center, Montreal, QC.
dDepartment of Pathology, Sunnybrook Health Sciences Centre, Toronto, ON.

Objective: Papillary renal cell carcinoma (PRCC) is comprised of two histological subtypes. PRCC2 is more aggressive and molecularly distinct from PRCC1. Despite this PRCCs are clinically treated as one entity, with lack of any evidence-based management recommendations. We have previously detected ABCC2 (ABC transporter) and mTOR pathway to be enriched in PRCC2. In this study we assess the therapeutic potential of targeting these pathways in PRCC2.

Methods: Bioinformatics analysis was performed on twenty RCC cell lines and compared to the PRCC2 signature derived from cancer genome atlas cohort (290 cases). Selected cell lines were grown in vitro and in vivo. Cells were treated with five different conditions, untreated, anti-VEGF (Sunitinib), ABCC2 blocker (MK571), mTOR inhibitor (Everolimus) and Sunitinib + MK571. Tumor Sunitinib uptake and apoptosis were measured by flow cytometry. Mice tumors were examined histologically and Ki67 was quantified with digital analysis.

Data and Results: The Sunitinb+ABCC2 blocker group showed significant response to therapy both in vitro (p = <0.0001) and in vivo (p = 0.0132). ABCC2 blockage resulted in almost double the uptake of Sunitinib, (p= 0.0016). The Everolimus treated group demonstrated second best response in vivo. The dual treatment group showed the highest apoptotic, and lowest ki67 proliferation rate.

Conclusion: There is need for individualized therapies of RCC subtypes that take into account their specific biology. Our study demonstrates that targeting ABC transporter ABCC2 in PRCC2 has therapeutic potential. The results are also significant for similar ABCC2 high tumors. Clinical trials are needed to confirm these effects in patients.

Keywords: Papillary renal cell carcinoma, Targeted therapy, ABC drug transporters

Back To Top

 

968 Genetic analysis of a combined small cell carcinoma and adenocarcinoma of the lung

Katherine D. Lacha, Najmeh S. Alirezaieb, Jacek Majewskic,d, Sophie Camilleri-Broeta, Richard Frasera, Jonathan D. Spicerb, Pierre O. Fiseta.

aDepartment of Pathology, McGill University Health Centre, Montreal, QC.
bDepartment of Surgery, L.D. MacLean Surgical Research Laboratories, McGill University Health Centre, McGill University, Montreal, QC.
cDepartment of Human Genetics, McGill University, Montreal, QC.
dGénome Québec Innovation Centre, Montreal, QC.

Background: Combined small cell lung carcinoma consists of small cell carcinoma and another histologic type of non-small cell lung carcinoma. Little is known of the mutation spectrum of this malignancy, and whether it results from a common precursor or from two independent tumors. We present a case of a 73-year old male ex-smoker who presented with hemoptysis. Investigations revealed a left lower lobe mass and a left mainstem endobronchial tumor. Surgical resection of the lower lobe tumor showed a combined small cell carcinoma and adenocarcinoma. The endobronchial tumor showed only small cell carcinoma. Foci of metastatic adenocarcinoma were found in regional lymph nodes.

Methods: Immunohistochemistry (cytokeratin 7, Napsin A, TTF-1, CD56, synaptophysin and chromogranin) and mucin stains (PAS, PAS-D and mucicarmine) were performed. DNA was extracted from formalin-fixed paraffin-embedded tissue, targeting morphologically distinct areas. The DNA was analyzed using whole-exome sequencing (WES).

Results: Neuroendocrine staining was limited to the small cell carcinoma, while epithelial marker and mucin stains were positive in the adenocarcinoma only. WES showed that the small cell component of both the primary and metastatic site harbored characteristic mutations including RB1, TP53 and EP300. By comparison, the adenocarcinoma component showed mutations in KRAS and EYA1.

Conclusions: This is a rare case of a surgically resected combined small cell carcinoma and adenocarcinoma, with distinct histologic and immunohistochemical phenotypes. With whole exome sequencing, two distinct genetic phenotypes were present providing evidence that the tumour was a collision tumour.

Keywords: Collision tumor; Whole exome sequencing; combined small cell lung carcinoma

Back To Top

 

P969 Pathology Cancer Clinic – An Innovative Model to Enhance the Quality of Patient Care for Women with Gynecologic Cancer at The Ottawa Hospital

Osama A. Khana, Anthea J. Lafrenierea, Aurelia Buscaa, George Grayb, Stephanie Petkiewicza, K. Williamsc, Tien Leb, Johanne L. Weberpalsb, Laura Hopkinsb, Shahidul Islama.

aDivision of Anatomical Pathology, The Ottawa Hospital / University of Ottawa, Ottawa.
b.Division of Gynecological Oncology, The Ottawa Hospital / University of Ottawa, Ottawa
cOntario Forensic Pathology Service, University of Toronto.

Background: Gynecologic cancer is a major issue in women’s health, with ovarian cancer representing the fifth leading cause of cancer-related death. Coping with a cancer diagnosis can be overwhelming for a multitude of reasons including the breadth of information received. Pathology reports are a valuable resource however, it can be difficult to understand due to the specialized language utilized.

Objective: To assess if patients’ involvement in a pathology clinic based setting will improve their understanding of their diagnosis and contribute to enhanced satisfaction in their quality of care.

Methods: Interested patients are recruited from the gynecology oncology clinics. During the clinic appointment, which is led by anatomical pathology residents, pathology reports and histological slides are reviewed in detail. Patients are asked to complete survey questionnaires before and after the session. Survey data are collated to determine if the consultation experience was beneficial.

Data and Results: We are currently in the process of recruitment, having interviewed five patients. Our goal is to recruit at least 20 patients, which will allow us to draw meaningful conclusions on the impact of a pathology clinic based setting.

Conclusions: This project is based on the collaboration of a multidisciplinary healthcare team to reinforce a culture of patient-focused care. We expect that patients will find the experience to be a positive which will contribute to their involvement in their management plans. Ultimately, we hope this research will lead to the successful implementation of pathology clinics in both residency training programs and tertiary care centres.

Keywords: Pathology, Cancer, Clinic, Gynecology

Back To Top

 

P970 Retrospective study of diagnostic concordance of bile duct brushing cytology with histological follow-up

Hui Wang, Janine Benoit, Omar Al-Nourhji.

Department of Pathology and Laboratory Medicine, University of Saskatchewan, Saskatoon, SK.

Objective: Retrospective review of common bile duct brushing (CBDBR) cytology to assess diagnostic accuracy in our facility and identify cytomorphological pitfalls that leads to possible error/near miss.

Methods: All CBDBR specimens within Saskatoon Health Region from 2011 to 2017 were reviewed. 242 specimens from 196 patients were received during this time period. Among them, 57 patients had histological follow up. 53 cases (4 case’ slides are un-available) were independently blindly reviewed by two cytopathologists and discrepancies were resolved by mutual consensus. Pre-and post- review accuracy was analyzed. Cellularity, background necrosis, architectural and nuclear features of each case were assessed.

Data and Results: The pre- vs. post-review sensitivity, specificity, positive predictive value and negative predictive value are 44% vs. 33%, 100% vs. 100%, 100% vs. 100%, and 14% vs. 20%, respectively. There are 22 vs. 25 cases diagnosed with “atypical” or “suspicious” pre- and post-review, respectively, and not contributed to accuracy analysis. The agreement between 2 cytopathologists is 49%. There are 2 cases with benign histologic follow up were diagnosed with “suspicious” in both pre-and post-review. The most significant cytomorphological features favoring malignancy are anisonucleosis, irregular nuclear membrane, and irregular chromatin distribution.

Conclusions: CBDBR cytology interpretation is extremely challenging without knowing patient’s clinical history and radiological findings. The inter-observer agreement is relatively fair. “Atypical” and “suspicious” are intermediate categories that pending further investigation in our study.

Keywords: bile duct brushing, retrospective study, accuracy, cytological features

Back To Top

 

P971 Impact of Implementing Bar-Coding on Patient Safety at the QEII Anatomical Pathology Laboratory

Geldenhuys L, Urquhart R, Caines C, Dini A.

Introduction: Barcoding of specimens in anatomical pathology laboratories is increasingly used to improve patient safety by reducing laboratory errors. These systems are, however, costly, and while they may improve efficiency in some areas of the laboratory, may slow down processing in others. Quantitative evidence of significant error reduction would be helpful to justify implementation of these systems.

Methods: We searched for patient safety reports and non-confirming events in the patient safety reporting system at the QEII Hospital two years prior to (2012 and 2013) and two years following (2014 and 2015) the implementation of a barcoding system in the QEII Anatomical Pathology Laboratory. We reviewed the events recorded, confirmed which events qualified as cassette, block and slide labeling errors, and analyzed the data.

Results: Block, cassette and slide labeling errors decreased from a total of 163 events, and a monthly average of 6.79 events, in the two years prior to implementation of barcoding to a total of 18 events, and a monthly average of 0.75 events, in the two years following implementation. This represents a substantial reduction in errors, and improvement in patient safety.

Conclusions: Barcoding of specimens in anatomical pathology laboratories significantly reduces cassette, block and slide labeling errors, improving patient safety. Additional studies examining the changes in resource requirements associated with the implementation would be helpful to assist laboratories in planning and developing a business case for implementation of barcoding.

Back To Top

 

P972 Immunohistochemical analysis of the transferrin receptor CD71 in precursor lesions and carcinomas of the esophagus

Shawn Winera,b, Yugo Iwayab, Corwyn Rowsella,e, Daniel Winerc,e, Maria Ciroccob, Lothar Lilged, Catherine Streutker1a,e, Norman Marconb,e.

aDivision of Pathology, St. Michael’s Hospital, M5B 1W8, Toronto, ON.
bDivision of Gastroenterology, St. Michael’s Hospital, M5B 1W8, Toronto, ON.
cDepartment of Pathology, University Health Network, 200 Elizabeth Street, M5G 2C4, Toronto, ON.
dDepartment of Medical Biophysics, University of Toronto, 101 College Street, M5G 1L7, Toronto, ON.
eDepartment of Laboratory Medicine and Pathobiology, University of Toronto, 1 King’s College Circle, M5S 1A8, Toronto ON.

Objective: Esophageal carcinoma, including squamous cell carcinoma (SCC) and adenocarcinoma, is a leading cause of cancer related deaths. One emerging mechanism of cancer cell growth utilizes the micronutrient iron, which is up-taken by squamous and glandular epithelial cells through its transferrin receptor (CD71). The aim of this study is to characterize CD71 expression in esophageal carcinomas and their precursor lesions.

Method: 123 esophageal biopsy or endoscopic mucosal resection samples from 81 patients were immunostained with a CD71 monoclonal antibody (Roche). CD71 expression was scored using a custom system from 0 (absent) to 3 (strong).

Results: Moderate to strong membranous and cytoplasmic CD71 staining was seen almost universally (97.2%) in both SCC and adenocarcinoma. In both squamous and glandular lesions, there was significantly stronger expression of CD71 in high-grade dysplasia (HGD) and carcinomas compared to the corresponding low-grade dysplasia (LGD), normal squamous mucosa or intestinal metaplasia (P <0.02). There was no difference in CD71 expression between reactive squamous mucosa and LGD; however for intestinal metaplasia, there was reduced surface expression of CD71 compared to LGD (P<0.01). The sensitivity of moderate to high CD71 expression for the detection of squamous and glandular HGD or carcinoma was 96.3% and 97.3%, while the specificity was 75% and 78.6%.

Conclusions: CD71 is upregulated in HGD and carcinomas of the esophagus, and may provide useful information in distinguishing reactive and LGD lesions from HGD. CD71 may represent an important target for the development of local therapy aimed at HGD precursor lesions and cancers of the esophagus.

Keywords: Esophagus, dysplasia, carcinoma, CD71

Back To Top

 

P973 Histological elucidation of tumour deposits in colorectal adenocarcinoma

Paul Plantinga, David Driman.

Department of Pathology and Laboratory Medicine, London Health Sciences Centre.

Introduction: Tumour deposits (TDs) in colorectal carcinomas are discrete tumour nodules within the pericolorectal fat, within the lymphatic drainage of the primary carcinoma, away from the tumour leading edge, and lacking residual lymph node. According to the TMN Classification, 7th edition, TDs are classified – similarly to positive lymph nodes – as pN1c (stage III). Such patients typically receive adjuvant therapy. In the 8th edition, the definition is clarified, such that, if a vessel wall or neural structure is identified, these nodules are no longer classified as TDs. This decreases patient stage (stage II), and adjuvant therapy may not be administered.

Methods: To examine the origin of TDs, 50 historical cases classified as pN1c are being identified and retrieved from the LHSC Pathology database. Cases with no identifiable TD will be excluded. Blocks containing TDs will undergo deeper sectioning to exclude direct extension from the primary tumour. In addition, elastin stains and S100 protein immunohistochemistry will be performed to identify vein walls and neural tissue, to aid in classification as venous or perineural invasion.

Results: Preliminary results of 58 TDs reveal 5 with perineural, 9 with venous invasion, and 1 additional TD showing both. The remaining 43 TDs remain classified as TDs.

Discussion: These preliminary results show that several TDs in fact would be regarded as venous and/or perineural invasion, thereby potentially down-staging patients from stage III to stage II. This will aid pathologists by encouraging further examination of so-called TDs in colorectal adenocarcinoma, and may reduce unnecessary treatment.

Keywords: colon cancer, rectal cancer, tumour deposits, tumour nodules, colorectal adenocarcinoma

Back To Top

 

P974 A 20-Year Review of Hospital Autopsies in a Nigerian Tertiary Hospital

Luqman, A.Adebayo, Abdullateeph, A.Odukoya, Nzechukwu, Z.Ikeri, Olakanmi, R.Akinde.

Lagos University Teaching Hospital, Lagos, Lagos, Nigeria.

Background: The hospital autopsy often serves as an audit of clinical practice. It also provides useful epidemiological data about the causes of mortality in the society, though requests for autopsy might not be made for conditions where the cause and course of disease is well understood. The changing trends of disease incidence and outcomes can also be captured by autopsy studies and it serves to realign public health initiatives in the prevention and treatment of common illnesses. The aim of this study was to assess the patterns of mortality that were confirmed by autopsy in our institution over a 20-year period.

Design: Data which included the age, sex and cause of death were retrieved from the departmental archives from January 1996 to December 2015. The causes of death were classified into categories which included but were not limited to infectious, cardiovascular-related deaths, trauma, malignancy, pregnancy-related, perinatal etc. These were analyzed and represented in tables, charts and graphs.

Results: The number of deaths that met the inclusion criteria were 3115. Of these, the majority (31.9%) were seen in the 20-40 year age group. Most paediatric deaths (0-20years) occurred in the perinatal period (39.7.8%). Outside the neonatal age group, infections were the commonest cause of death in children (53.8%). The commonest causes of death in adults were related to diseases of the cardiovascular system (25.5%), though trauma was the commonest cause of death in males aged 20-40yrs, and pregnancy-related deaths were the commonest causes of death in females of that same age group. Death due to malignancies and cardiovascularrelated deaths were each seen most commonly in the 40-60yrs age bracket. Death associated with congential abnormalities occured predominantly in infants. Over the years, there was a steady increase in the rate of deaths arising from cardiovascular diseases, which eventually replaced trauma as the commonest cause of adult deaths seen at autopsy.

Conclusions: The increased prevalence of cardiovascular disease-related deaths shows the adoption of western lifestyle by inhabitants of Lagos.

Keywords: Autopsy

Back To Top

 

P975 Pathology Education in the 1900s: Looking through the magic lantern glass slide

Ayesha Baiga, Richard Frasera,b.

aDepartment of Anatomical Pathology, McGill University, Montreal, QC.
bMaude Abbott Medical Museum, Montreal, QC.

Objective: Pathology teaching relies heavily on images of disease. Over the years, the means to show these has included woodcuts, engravings, “Kodachrome” slides and digital representations. In the first part of the twentieth century, lantern slides were also a particularly important tool. We wished to see how many such slides remained at McGill and what they showed, in order to help understand pathology teaching at the time.

Methods: We searched the archives of various McGill associated institutions – including the Maude Abbott Medical Museum (MAMM), McGill University Archives, Osler Library of the History of Medicine, McCord Museum and MUHC Art and Heritage Center) – for lantern slide collections.

Data and Results: 1402 lantern slides were identified in the MAMM. Although smaller collections were found in the other institutions, none included examples of pathological material. The MAMM slides included 605 gross, 342 microscopic, 127 electron microscopic and 80 x-ray images as well as a variety of tables, texts, graphs and hand drawings. The majority were produced at McGill between 1940 and 1960. Most have hand written labels with unique ID numbers and a brief description of the lesion/disease depicted.

Conclusions: Lantern slides were a useful tool to teach pathology at McGill in the mid-1900s. The collection which remains gives a glimpse into the types of disease encountered and how they were taught at this time. As a means of ordering thoughts and presenting images of disease, the slides foreshadow our current power point presentations.

Keywords: Pathology education, lantern slides, gross images, microscopic images, x-ray images

Back To Top

 

P976 Colorectal polyps in childhood cancer survivors treated with radiation therapy

Sammy Aua, Nazira Chaturb, Vladimir Marquezb, Fergal Donnellanb, Baljinder S. Salhb, Michael Nimmoa, Karen J. Goddardc, Majid Alsahafid.

aDepartment of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC.
bDivision of Gastroenterology, Department of Medicine, University of British Columbia, Vancouver, BC.
cDepartment of Radiation Oncology, British Columbia Cancer Agency, Vancouver, BC.
dDepartment of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.

Objective: Cancer survivors treated with abdominal or pelvic radiation therapy (RT) for childhood cancer have an increased risk of colorectal cancer. However, clinical guidelines are inconsistent on recommendations regarding the early initiation of screening in these patients due to the lack of supporting evidence that these patients pass through a pre-invasive phase, in which adenomatous polyps can be detected and removed. In our study, we aim to determine the prevalence of adenomas in this population.

Methods: We conducted a retrospective study comparing the prevalence of adenomatous polyps among three patient groups: childhood cancer survivors aged 17 to 49 with prior RT who underwent colonoscopy screening from 2006 to 2017; age- and gender-matched patients in the average-risk population; and average-risk patients aged 50-75.

Data and Results: A total of 145 patients were included in the study (29 childhood cancer survivors, 58 average-risk patients aged 17-49, and 58 average-risk patients aged 50-75). The proportion of patients with adenomas in the survivor group was significantly higher than that in the age- and gender-matched average-risk group (58.6% vs 17.2%, p<0.05) and higher than the average-risk group aged 50-75 (58.6% vs 27.6%, p<0.05). The prevalence of adenomas with high-risk features was higher in the survivor group compared to patients aged 50-75 (20.7% vs 3.5%, p<0.05).

Conclusions: Childhood cancer survivors treated with RT have a higher prevalence of adenomatous polyps compared to average-risk patients in the same age group and compared to average-risk patients aged 50-75. These findings support the initiation of colonoscopy screening earlier than the average-risk population.

Keywords: Colorectal polyp, screening colonoscopy

Back To Top

 

P977 The prevalence of Programmed Death Ligand 1 (PD-L1) in tumour-infiltrating immune cells is common in Canadian patients with invasive urothelial carcinoma

Gilbert Bigrasa, Fadi Brimob, Michelle R. Downesc, Mathieu Latourd, Peyman Tavassolie, Kelly Fathersf, Cloris Xuef, Patricia DeMarcof, Carol Cheungg.

aDepartment of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB.
bDepartment of Pathology, McGill University, Montreal, QC.
cDepartment of Anatomic Pathology, Sunnybrook Health Sciences Centre, Toronto, ON.
dDépartement de pathologie; Centre hospitalier de l’Université de Montréal, Montreal, QC.
eDepartment of Pathology, Kelowna General Hospital, Kelowna, BC.
fDepartment of Medical Affairs, Hoffmann-La Roche Ltd, Mississauga, ON.
gDepartment of Pathology, University Health Network, Toronto, ON.

Urothelial carcinoma (UC) is the most common form of bladder cancer. Although the 5-year overall survival rate of bladder cancer is 73%, the outcome for patients with metastatic UC remains poor. Programmed death ligand 1 (PD-L1) is over-expressed by many cancers, and facilitates tumour evasion of host immune responses via the PD-L1/PD-1 checkpoint. Immunotherapy is an emerging paradigm for the treatment of advanced UC with recent clinical trials demonstrating significant responses in patients by blocking PD-1/PD-L1. Nonetheless, the data on the prevalence of PD-L1 in urothelial tumours is limited. The goal of this study was to evaluate the prevalence of PD-L1 expression in tumour-infiltrating immune cells (IC) in UC in Canada and to correlate its expression with multiple clinical and pathological parameters. Three hundred archived UC specimens from six Canadian sites were assessed for PD-L1 expression using the Ventana PD-L1 (SP142) immunohistochemistry assay. The presence of discernible PD-L1 signal in tumour-infiltrating IC involving ≥5% of tumour with associated stroma was deemed “positive” and was observed in 39% (CI 33.13-44.43%) of specimens tested. There was no relationship between positivity of the PD-L1 assay and several clinicopathological parameters, including age, gender, and tumour location. Notably, PD-L1 expression of tumour-infiltrating IC exhibited a significant association with tumour stage (p=0.0409), with a trend towards higher PD-L1 positivity in more advanced tumours. In conclusion, PD-L1 expression in tumour-infiltrating IC is common in UC in Canada and may be associated with more advanced stage cancers, reinforcing that PD-L1 may be a relevant therapeutic target for UC.

Keywords: PD-L1; tumour-infiltrating immune cells; urothelial carcinoma; immunotherapy

Back To Top

 

P978 Benign lymphangioendothelioma in the setting of chronic lymphedema following prior treatment for breast carcinoma – a case report

Tamadar Aldoheyan, Sete Hamza.

Introduction: Benign lymphangioendothelioma (acquired progressive lymphangioma) is a rare slow-growing lymphatic vascular proliferation. It is characterized histologically by a dissecting growth pattern that can mimic malignancy. Its occurrence in the setting of chronic lymphedema is exceedingly rare.

Clinical Presentation: A 64-year-old woman presented with several papules and nodules mainly located around the elbow of her chronically lymphedematous right arm. The chronic lymphedema resulted from treatment of a right breast carcinoma more than 12 years prior to presentation. The treatment included right breast lumpectomy and axillary lymph node dissection, followed by adjuvant radiation therapy. The lymphedema has been managed by using a compression sleeve along with periodic massage therapy. The cutaneous lesions appeared the following year and were said to have very slow growth throughout the years. Despite the indolent clinical course, there was a clinical concern for angiosarcoma leading to biopsies of two of the lesions, a nodule on the elbow and a papule on the arm.

Results: Sections of the nodule showed a vascular proliferation that involved and expanded the dermis and upper subcutis. It was composed of irregularly shaped thin-walled vessels lined by a bland flattened single-layered endothelial cell lining, without significant nuclear atypia or multilayering. The vessels were present in a diffuse manner in the dermis, with dissecting of dermal collagen fibers. Some of the vessels contained faint proteinaceous material. There was a vascular proliferation in the arm papule as well. It was dermal and was composed of small collapsed vessels present interstitially, also with a dissecting growth pattern, associated with some chronic mononuclear inflammatory cells and some extravasated red blood cells. With immunostains, the vessels were positive for CD31, factor VIII-related antigen and D2-40. They were negative for HHV8 and showed no significant staining with c-MYC and Ki67. The lesional vessels were also negative for WT-1, which only highlighted some small vessels present in the background stroma.

Conclusion: Benign lymphangioendothelioma can very rarely occur in the setting of chronic lymphedema of the arm in breast carcinoma patients. Its dissecting growth pattern may initially suggest the possibility of more aggressive vascular proliferations. Its decidedly indolent clinical course is an important clue to the diagnosis, which can be confirmed by immunohistochemistry.

Back To Top

 

P979 A retrospective analysis of microscopic colitis: associated ancillary histological features revealed

Rachel Juga, Krista Edelmanb, Rachel Federb, Robin Vollmerc, Daniel Wildb, Diana Cardonaa.

aDepartment of Pathology, Duke University Medical Center, Durham, NC.
bDepartment of Gastroenterology, Duke University Medical Center, Durham, NC.
cDepartment of Pathology, Durham VA Hospital, Durham, NC.

Objective: Microscopic colitis (MC), encompassing collagenous colitis (CC) and lymphocytic colitis (LC), is histologically defined by basement membrane thickness (BMT) >10 µm and intraepithelial lymphocytosis (IEL; >20/100 enterocytes), respectively. The etiology is unknown and likely multifactorial, resulting in varied morphologies. We aim to determine the associations of ancillary histologic findings in MC.

Methods: A retrospective search of our Laboratory Information System (LIS) between 1/1/2001-1/1/2016 for cases of MC and controls was performed. Diagnostic histologic features and novel findings were recorded for each case. Standard statistical methods were used for data analysis.

Data and Results: There were 163 cases of MC (100 LC, 56 CC, 7 mixed MC) and 20 controls. As expected, statistical analysis revealed surface IEL and BMT (Table 1) were positively associated with MC while surface ulceration and acute inflammation (p~0) were negatively associated with MC. Interestingly, lamina propria eosinophilia was markedly associated with MC. BMT ≥15 µm and 50 IEL were associated with CC 100% and LC 86% of the time, respectively. Logistic regression showed epithelial damage was not associated with IELs or BMT.

Table 1: Histologic Features of Microscopic Colitis.

Diagnosis

Number of Cases

Intraepithelial Lymphocytes
Mean/100 enterocytes (range)
(P value ~0)

Basement Membrane Thickness (µm)
Mean (range)
(P value ~0)

Lamina Propria Eosinophils
Mean/5 high power fields (range)
(P value ~0)

Lymphocytic colitis

100

66.3 (13-160)

2.7 (1-17)

111 (2-394)

Collagenous colitis

56

32.4 (8-99)

16.3 (2-42)

176 (8-450)

Control group

20

20.6 (6-62)

1.2 (1-3)

53.9 (0-216)

Conclusions: Ancillary histologic features and certain thresholds, such as increased eosinophils and BMT, may prove to be diagnostically useful, especially in borderline cases.

Keywords: microscopic colitis, lymphocytic colitis, collagenous colitis, histology

Back To Top

 

P980 Cutaneous plasmacytosis and multinucleate cell angiohistiocytoma in a patient with hepatitis B – a case report

Simon F. Roya, , Feras M. Ghazawib, Danielle Bouffarda.

aDivision of Pathology, University of Montreal, Montreal, Quebec.
bDivision of Dermatology, University of Ottawa, Ottawa, Ontario.

Introduction: Cutaneous plasmacytosis is a rare entity, affecting patients of predominantly Asian descent. Multinucleate cell angiohistiocytoma (MCAH) is a vascular proliferation of unknown etiology, thought to be reactive in origin. We present here the case of a patient with both skin diseases occurring concomitantly, in the context of chronic hepatitis B infection.

Clinical Presentation: A 28-year-old Chinese female presented with a 7-year history of erythematous-brown papules and plaques on her groin, axillae and forehead. Her hepatitis B e antigen-negative mutant variant had transitioned from active phase of disease, to an inactive carrier state, with HBV DNA levels below 20 IU/ml. Upon serum protein electrophoresis gamma globulin levels were elevated at 21.05 g/L (IgG fraction, 24 g/L). A bone marrow aspirate revealed only 1% of polyclonal plasmocytes.

Results: A skin biopsy revealed findings consistent with two concomitant yet uncommon cutaneous skin diseases. The presence of lymphoid nodules with germinal centers and clustered polyclonal plasma cells was consistent with cutaneous plasmocytosis. Second, a diffuse proliferation of non-atypical small vessels (CD31+,CD34+ and HHV8-) in a hypercellular stroma including many angulated multinucleated cells (CD163+, CD68+) was suggestive of MCAH.

Conclusions: We speculate the immune modulating effects of chronic hepatitis B may have led to a plasmacytic proliferation within the dermis. Furthermore, MCAH has been reported in conjunction with other skin diseases such as xanthelasma or squamous cell carcinoma and as such we propose that the MCAH lesion in our case to be secondary to the cutaneous plasmacytosis.

Back To Top

 

P981 Voided urine cytology, not everything great comes in threes. An institutional audit and report

Pouya Sadeghi Aval, Heather MacIntyre, Emily Filter, Jennifer Merrimen, Cheng Wang.

Department of Pathology, Dalhousie University, Halifax, NS.

Background: The main objective of urine cytology is to detect high grade urothelial carcinoma. Canadian guidelines on indications for voided urine cytology are dated and vague, which has led to variable testing practices. Additionally, some clinicians insist on serial samples to increase the sensitivity of this test. This has led to an increase in cytology workload at our institution.

Methods: We retrospectively searched our laboratory database for both voided and non-voided urine cytology results between January 2012 and September of 2017. Voided urines with suggestive/suspicious/positive results were identified, with subsequent review of patient charts.

Results: A total of 26066 urine cytology results were identified, of which 5999 (23%) were voided specimens. Only 56 (0.93%) of the voided urines were signed out as suggestive/suspicious/positive. These 56 specimens were from 41 patients (mean age: 75 years old), as 7 patients had serial testing in triplicates or duplicates. The results of the serial samples in those 7 patients were congruent.

Conclusions: Voided urine cytology has variable sensitivity in detecting high grade urothelial carcinoma. Despite old literature and beliefs that serial testing increases sensitivity, this does not appear to be the case at our institution. Eliminating serial voided urine testing would cut down operational and opportunity costs, without impacting patient care.

Keywords: Urine cytology, Voided urine, Urothelial carcinoma

Back To Top

 

P982 Novel immunostaining with p40 in sarcomatoid squamous-cell carcinoma of the vulva – A case report

James N. Macphersona, Omar Al-Nourhjia, Mary A Kinlocha.

aDepartment of Pathology and Laboratory Medicine, University of Saskatchewan, Saskatoon, SK.

Introduction: Sarcomatoid (spindle-cell) squamous-cell carcinoma (SCC), is a rare, aggressive variant of vulvar SCC with a spindle-cell component of variable cellularity and atypia. Histologic diagnosis of these tumors is challenging, especially in small biopsy specimens. In the absence of overlying dysplasia or admixed conventional component, immunohistochemical staining becomes imperative in establishing the diagnosis. While the squamous-cell component of these lesions reliably stain with markers for cytokeratins, the spindle-cell component can be negative for these markers.

Clinical Presentation: We describe the case of a 69-year-old woman who presented with a progressively enlarging midline vulvar lesion, which completely obliterated the clitoris over a 6-month period. The initial biopsy of this lesion demonstrated a mix of poorly-differentiated spindle and squamous cells, precluding a diagnosis on histomorphology alone.

Results: In the presenting lesion, cytokeratin stain CK5 was positive in the cytoplasm of the poorly-differentiated squamous cells but did not stain the spindle-cells. In contrast, the entire lesion stained positively for the nuclear marker p40.

Conclusion: Vulvar sarcomatoid SCC is a rare entity with less than 25 previous cases reported. While p40 staining has been reported in other sites, no prior instances of vulvar sarcomatoid SCC staining with p40 have been reported. In this case, the p40 staining assisted in diagnosing the spindle-cell component as a metaplastic process of SCC rather than carcinosarcoma.

Back To Top

 

P983 Perceptions of pathologists, pathologist residents, and pathologist’s assistants on non-forensic autopsies: a qualitative study

Avneet K. Dhardwar1, Bertha Garcia1.

1Department of Pathology and Laboratory Medicine, Western University, London ON.

The rate of non-forensic autopsies has been declining drastically in most developed countries since the 1960s (1). Previous studies have described autopsy as the “golden standard” procedure not only because of its utility as a quality control measure to determine the quality and/or effectiveness of treatment but also because of its role in helping to understand diseases and providing information that is not detected to the same degree or at all by imaging (2,3). This study’s aim was to gather information from pathologists, pathologist residents, and pathologist’s assistants working at University Hospital in London, Ontario, to learn more about why the non-forensic autopsy rates are declining and how this trend can be reversed.

A qualitative, phenomenological approach was taken where participants answered open-ended questions in semi-structured, one-on-one interviews. Each group of professionals provided unique perspectives on autopsies based on their varying extent of work experiences and diverse personal attitudes towards autopsies.

Almost all the professionals discussed the difficulties they encountered as a result of clinicians filling out consent forms for autopsies incorrectly. The majority of professionals also described how in general, clinicians and the public lack knowledge on autopsies, what they consist of, and their purposes. This explains why many pathologists and pathologist’s assistants felt that non-forensic autopsies are sometimes performed when pathologists would agree it is not the best use of resources. The information retrieved from these interviews could be used to influence specific interventions designed to improve the usefulness of autopsies as well as their rates, when necessary.

Keywords: Autopsy, post-mortem, pathologist, perceptions, attitudes

Back To Top

 

P984 Neurocristic cutaneous hamartoma in a newborn: a case report and literature review

Brigitte Courteaua, Sarab Mohameda,b, Gabriella Gohlaa,c, Samih Salamaa,c, Salem Alowamia,c.

aDepartment of Pathology and Molecular Medicine.
bMcMaster University Hospital, Hamilton Ontario.
cSt. Joseph’s Healthcare, Hamilton, Ontario.

Introduction: Neurocristic cutaneous hamartoma (NCH) is a rare lesion of skin and subcutaneous tissue consisting of melanocytic and supportive cells of the peripheral nervous system. It typically presents congenitally on the face, scalp and back as a pigmented, keratotic nodule measuring 3-10cm. The differential diagnosis includes other melanocytic lesions and significantly overlaps with pigmented neurofibroma.

Clinical Presentation: An infant male was born with a giant melanocytic nevus covering 35% of his total body surface area, in a bath trunk distribution, and was submitted for histopathological examination.

Results: Grossly, the lesion was pale-tan, flat and hairy with central dimpling and punctate gray-black pigment. Microscopically, intradermal melanocytic nests were seen with pigmentation, spindle cell proliferation, thin collagen strands, small vascular channels and nerve fascicles with focal hyperkeratosis and mild acanthosis. Nuclear atypia was absent. Immunohistochemistry supported NCH with CD34 staining spindle cells, S100 staining melanocytes and the neural component, and Factor 13a staining the dermal dendritic cells.

– click here for figure

Conclusion: Because the clinical manifestations of NCH vary and have been associated with malignant neoplasms including melanoma, complete (or near-complete) excision while avoiding morbidity is recommended. This case documents the importance of recognition of NCH in a congenital nevus and the potential for misdiagnosis.

Back To Top

 

Pathologists’ Assistants Poster Abstracts

PA Posters will be presented on Saturday, July 7 between 1800-2000 during the PA Reception.

 

P701 The profile of a pathologists’ assistant (PA) in North America

Stephanie M. Sharpleya,b, Dr. Nancy Chanab, and Dr. Keith Kwanab.

aDepartment of Pathology and Laboratory Medicine, London Health Sciences Centre, London, Ontario.
bSchulich School of Medicine & Dentistry, Western University, London, Ontario.

Objective: The purpose of this study is to provide a comprehensive report of the demographics and practice characteristics of PA’s who work in the surgical gross room at various North American institutions.

Methods: Eligible participants are those who satisfy the definition of a PA set by the American Association of Pathologists’ Assistants (AAPA). Information from participants is collected via an anonymous, 22-question online survey that has been designed through a database called Qualtrics. Lab managers of each institutions’ Pathology department are contacted via email and provided with a link to the survey, access password, and information and consent letter, and are asked to distribute the email to the PA’s in the department.

Results: Analysis of responses obtained from 146 participants reveals that the PA demographic consists of individuals with a diverse range of interests and credentials, and there is a growing number of people electing to pursue a specific PA-training program before beginning their career. Thirty percent of respondents are also involved with other initiatives beyond the PA job description at their institution, demonstrating that this career affords many opportunities, even beyond the surgical gross room. Workplace-related injuries were reported by 44% of respondents, suggesting a need to further investigate potential safer techniques or improvements in practice.

Conclusion: Identifying the varied skills, knowledge, and initiatives brought forth by practicing PA’s, and assessing key areas of improvement to their roles, is essential to the evolution and standardization of the profession.

Keywords: pathology, gross room, pathologists’ assistant, healthcare

Back To Top

 

P702 Models and peer teaching as pedagogical methods in the surgical pathology laboratory

Emily G. M. Kyle1, Jose A. Gomez1,2, Nancy G. Chan1,2.

1Department of Pathology and Laboratory Medicine, Western University.
2Department of Pathology and Laboratory Medicine, London Health Sciences Centre.

Introduction: Pathologists’ Assistants (PAs) are highly trained health care professionals who examine (“gross”) patients’ surgical specimens for diagnosis and treatment planning. During their training, graduate students learn using real patient material.

Objective: To help prepare students for approaching patient samples, hands on activities using clay models and cheese strings were used to imitate prostatectomy and salpingectomy specimens respectively. Peer teaching was also assessed as a pedagogical method.

Methods: This study’s first author was taught to section an imitation prostate using a clay model and use the SEE-FIM protocol for salpingectomies using cheese strings. The clay model mimicked the anatomy and orientation of radical prostatectomy tissue encountered in the hospital laboratory. The cheese string was “stripped” on one end to imitate fimbriae. The student “teacher” then taught her classmates as well as first year pathology residents how to “gross” these cases.

Results: Students and residents generally felt more confident about their ability to handle prostatectomy and salpingectomy cases in the gross room after this hands on, peer led activity.
Some trainees noted they felt no significant difference between asking questions of a peer teacher compared to a pathologist.

Conclusions: Hands on activities using models provide a safe environment for teaching the approach to patients’ surgical specimens. Peer teaching is an effective pedagogical method.

Keywords: grossing, Pathologists’ Assistant, peer teaching, prostate, fallopian tube

Back To Top

 

P703 Impulsivity in Indigenous Suicide in Ontario, Canada

Rebecca Glover1, Gerald McKinley1.

1Department of Pathology and Laboratory Medicine, Western University.

Introduction: Suicide is the leading cause of death for people aged 15-34 in Canada, representing 23% of all deaths in the age group. Suicide among Indigenous youth is five to six times higher than non-Indigenous youth in Canada. This project explores impulsivity and triggering events, including domestic abuse and substance abuse, as well as previous self-harm, that move a person from ideation to suicidal behaviour.

Methods: This project uses a secondary analysis from a file review of 151 cases completed at the Office of the Chief Coroner, Ontario. The interval between last contact and the time of death of each deceased was measured, and the triggering events and social circumstances were recorded. The results were analyzed to assess a correlation between triggering events and impulsivity.

Results and Discussion: The data show a negative correlation with time since last contact and suicidal act. There is prevalent abuse, CAS involvement, and other trigger events in these cases, which have been shown to increase impulsivity in persons.

Conclusion: Further analysis will relate these triggering factors to the impulsive state. These correlations can be used to coordinate prevention and intervention methods designed specifically for at-risk populations.

Keywords: suicide, impulsivity, indigenous youth, youth suicide

Back To Top

 

P704 Hirschsprung disease with total colonic aganglionosis and small bowel involvement – a case report

Alyshia A. Phillipsa, Matthew J. Cecchinia, Joanna C. Walsha.

aDepartment of Pathology and Laboratory Medicine, Western University, London, ON.

Introduction: Hirschsprung disease (HD) is characterized by the absence of enteric ganglia along a variable length of intestine due to failure of neural crest cell migration from cecum to rectum, producing an intestinal portion that lacks the Meissner submucosal plexus and Auerbach myenteric plexus. Affected individuals typically present during the neonatal period with obstructive symptoms.

Clinical Presentation: A three-day old male initially presented with blood-tinged emesis and failure to pass meconium. Pregnancy was unremarkable apart from maternal drug use, spontaneous vaginal delivery was uncomplicated and no other congenital abnormalities were identified. He underwent an exploratory laparotomy and resection for ischemic bowel.

Results: Microscopic examination did not reveal any ganglion cells in the resected bowel. Rectum and ileostomy were biopsied and found to also be negative for ganglion cells. An additional resection of the aganglionic segment demonstrated prominent enterocolitis with ganglion cells identified in the jejunum on frozen section. This left only 65 cm of functional bowel remaining distal to the ligament of Treitz.

Conclusion: Worldwide, HD is estimated to occur once in every 5000 live births with a male predominance. Most affected individuals (80%) present with aganglionosis in the rectosigmoid colon. Less commonly, HD extends to total colonic aganglionosis (8-10%) and seldom (1%) the disease involves the proximal small bowel. This manifestation of long-segment HD has increased morbidity and mortality as the patient is at greater risk for long-term total parenteral nutrition, enterocolitis and short bowel syndrome. The presented case highlights an uncommon variant of HD involving proximal small bowel.

Keywords: Hirschsprung disease, total colonic aganglionosis, short bowel syndrome, total parenteral nutrition, enterocolitis

Back To Top

 

P705 Workload evaluation of submitting single versus multiple cervix LEEP sections per cassette

Todd Paron, Janice Kariatsumari, Sheri Bevandic, John Russell Rogers, Steve Tomasic, Julia Celebre, Patricia Ludlow, David Kuni, Hamid Kazerouni, Amir Salehi, Monalisa Sur, Alice Lytwyn.

Department of Pathology, Juravinski Hospital, Hamilton, Ontario.

Objective: Guidelines recommend 1 cervical LEEP section per cassette, oriented and submitted consecutively. Invasive carcinoma in consecutive versus non-consecutive sections impacts staging. We compared workload generated by oriented single sectioning/cassette (SSC), to our usual practice of multiple sections/cassette (MSC).

Methods: Consecutive LEEPs grossed by SSC or MSC over 4 months were identified by computerized pathology database search. We compared number of cassettes/case, stratified by number of LEEPs/case, and cassette numbers based on size (cm3) of each LEEP. We surveyed opinions on workload from Histotechnologists, Pathologist Assistants, and Pathologists using Survey Monkey.

Data and Results:

Table: Cassettes produced per case: SSC vs MSC

LEEPs/case

Single Section per Cassette
December 2017-January 2018
N=49 cases

Multiple Sections per Cassette
October 2017-November 2017
N=64 cases

Ratio mean no.
cassettes / case
SSC vs MSC

No. cases

Mean no.
cassettes/case

No. cases

Mean no.
cassettes/case

1

33

11

37

4.7

2.3

2

10

16.7

15

7.5

2.2

3

4

18

6

7.8

2.3

4

1

18

2

10.5

1.7

5

1

20

0

N/A

N/A

Based on tissue size (cm3), mean no. of cassettes/case was 10.8 and 4.4 for SSC vs MSC, respectively, a 2.5 fold increase. Six of 7 histotechnologists preferred embedding and cutting 1 piece/cassette; all agreed it was faster to obtain full section cuts. Four of 4 pathologist assistants felt SSC increased grossing time. Five of 6 pathologists preferred reading single section slides, reporting and measuring lesions was improved, and 3/6 reported faster signout.

Conclusions: SSC increases cassette number. Grossing time for pathology assistants is increased. Histotechnologists could obtain sufficient cuts faster. Most pathologists preferred single section slides.

Keywords: LEEP, cervix, workload evaluation

Back To Top

 

P706 Effect Of Different Strategies For Reduction Of Cold Ischemia Time In Breast Pathology

N. Nikzad, Y. Zhao, J.M. Yaholnitsky, M.J. Trotter, N. Myles.

Department of Pathology and Laboratory Medicine, Providence Health Care, St. Paul’s Hospital, University of British Columbia, Vancouver, BC.

Objective: The time from breast specimen removal to formalin fixation (Cold Ischemia Time – CIT) is a critical value which should not exceed one hour and should be monitored (ASCO2010/CAP2011). Prolonged CIT may adversely affect biomarker testing and tumour grading. As pathology departments undergo amalgamation and centralization, breast surgery services often remain decentralized leaving a remote site without pathology staff support. We address this system quality issue in our study.

Materials and Methods: We evaluated two strategies for reduction of CIT: (A) optimized specimen transfer to central facility and (B) direct handling of breast specimens by Pathologists’ Assistants (PAs) at the remote site. We captured, measured and plotted CIT for both strategies and historic baseline.

Result: Figure 1 shows observed CIT corresponding to the strategies used. The baseline mean CIT was 2 hrs 25 min, 2 h 15 min with strategy A and 44 min with strategy B. There are still a number of cases where CIT of 1 hour could not be met due to the other factors (specimen x-ray and multi-part surgeries).

– click here for figure

Conclusion: When operating with a remote surgical site in an urban setting, improved specimen delivery to a central site does not meet the one hour CIT. However, specimen handling by PAs directly at the remote site allowed the ASCO2010/CAP2011 standard to be achieved. Economic impact of both strategies should be evaluated against the risks of downstream testing errors due to delayed fixation. Based on our results we advocate for inclusion of PAs into pathology teams nationwide.

Keywords: Breast, Cold Ischemia Time

Back To Top

 

P707 Effect Of Pathologists’ Assistants On Turnaround Time For Surgical Pathology Specimens

N. Myles, Y. Zhao, N. Nikzad, J.M. Yaholnitsky, D.Holmes, M.J. Trotter.

Department of Pathology and Laboratory Medicine, Providence Health Care, St. Paul’s Hospital, University of British Columbia, Vancouver, BC.

Objective: Pathologists’ Assistants (PAs) are invaluable contributors to pathology services. However, research evidence for how PAs might influence pathologist productivity is lacking. In this study we compared turnaround time (TAT) for all classes of surgical pathology specimens before and after deployment of PAs for specimen grossing.

Materials and Methods: The TAT data (total 4001 cases) for all surgical pathology specimen types were completed within two similar service periods (in terms of work load, work force, month of the year and presence of residents in the department) using time to event univariate and multivariate analyses (using log rank test and Cox regression adjusting to individual pathologist TAT as a co-variate comparing TAT before and after PA implementation).

Results: There was a statistically significant difference in TAT between two service periods (log-rank test p=0.001), with shorter TAT after the implementation of PAs. A striking effect of elimination of outlier cases (with TAT of more than 20 days) was noted (18 cases vs. 1) after PA deployment (Figure 1). TATs appear pathologist-driven, yet an overall TAT improvement was achieved.

– click here for figure

Conclusion: The use of PAs allowed a marked reduction in TAT for the most complex outlier cases. Although the proportion of these cases appears small, they represent the main potential sources for complaints, delayed patient appointments and delayed post-surgical patient care. Therefore, the elimination of TAT outliers is essential for optimal and timely pathology delivery.

Keywords: Turnaround Time, Pathology

Back To Top

 

P708 The Use of CT in Forensic Post Mortem Examination to Facilitate Targeted Dissection Methods

Erika Chadwick1, Art Poon1, Michael Pickup2.

1Department of Pathology and Laboratory Medicine, Western University.
2Ontario Forensic Pathology Services, Toronto, ON.

Introduction: Computed Tomography (CT) is a non-invasive diagnostic imaging technique that is frequently being used in forensic post-mortem examination to aid pathologists in determination of cause of death. CT is a tool that can be used to supplement autopsy by creating detailed cross-sectional images of the body through associated x-ray measurements. CT imaging can be a useful method in identification of individuals, preservation of evidence and identifying hazards present in a post-mortem exam. This retrospective study will investigate a randomly selected population of cases from 2015 and 2017 to evaluate the usefulness of CT to motivate the pathologist to perform a targeted dissection or an external exam.

Methods: We randomly selected 100 cases; 50 cases from both 2017 and 50 cases from 2015; to analyze. The statistics from each case were compared to evaluate if CT a reliable non-invasive technique to encourage more targeted dissections, and in what situation is CT the most effective.

Results: Between both sets of data, it was proven that the most common death causes were drug toxicity, cardiovascular disease and severe trauma. The time difference between full autopsies and targeted autopsies was significant (P <0.001). It was shown that CT is most useful for traumatic deaths and cardiovascular disease, whereas forensic chemistry was most useful in determining the cause of death for drug toxicity.

Conclusions: Although full post-mortem examinations are the most reliable method, it can be shown that CT is a supplementary tool that can be beneficial for decreasing workload and exposure.

Keywords: forensic pathology, post-mortem examination, computed tomography, post-mortem CT

Back To Top

 

P709 Testicular hemangioma mimicking cystic dysplasia of the testis – a case report

Nicole A. Smith, Emily Goebel, Bret Wehrli, Jose A. Gomez, Nancy G. Chan.

Department of Pathology and Laboratory Medicine, Western University and London Health Sciences Centre, London, ON.

Introduction: Testicular hemangiomas are very rare, benign tumours resulting from blood vessel proliferation within the testes. They occur predominantly in infants and young adults. Cystic dysplasia is another rare, benign condition affecting the testes which arises due to cystic dilation of the rete testis. Ultrasound has been shown to be the most reliable and accurate method for analysing scrotal abnormalities in children—cystic dysplasia often demonstrates cystic lesions within the upper pole of the testis and testicular hemangiomas often show hypoechoic and hypervascular lesions. However, our case demonstrates that final diagnosis relies on histopathological evaluation.

Clinical presentation: A 3 week old male presented with a right scrotal mass and hydrocele. Ultrasound showed a mildly enlarged testicle with heterogeneous echotexture and multiple areas of anechoic cysts replacing the testicular tissue. Bilateral vascular flow was demonstrated with Doppler ultrasound. Testicular tumour markers were within the normal range. Based on these findings, it was believed that the enlargement was cystic dysplasia of the testis. An orchiectomy was performed at 8 months.

Results: On pathological examination, the testicle contained an ill-defined pale tan lesion. Histologically, the sections showed a vascular proliferation within the spermatic cord which showed positive immunohistochemical staining for CD31. Also present was a wedge infarct replacing approximately 75% of the testicle.

Discussion: Ultrasound is a good method for analysing scrotal masses in children and can help differentiate between benign and malignant conditions. However, histopathology may be required for definitive diagnosis.

Keywords: hemangioma, cystic dysplasia, testis, pediatric pathology

Back To Top

 

P710 Scope of Practice Descriptions Vary for Pathologists’ Assistants in Alberta, Manitoba, and Ontario

Chan, Ainsley, Keelan, Monika; Mather, Cheryl; Lee, Danielle.

Background and Aim: Pathologists’ Assistants (PAs) working in surgical pathology are highly skilled medical laboratory personnel who describe and dissect surgical resection specimens to contribute diagnostic and prognostic information. However, as a newly certified profession in Canada, there is no universally accepted national standard describing PAs’ responsibilities. The main objective of this study is to identify differences in practices and language to move toward establishing a national competency profile for the PA profession by first interviewing program directors of the Master’s degree PA (MPA) training programs and PAs in Canada.

Material and Methods: 4 MPA program directors, 1 assistant program director (PA) and 1 program coordinator (PA) (at the Universities of Alberta, Calgary, Manitoba, and Western Ontario) were interviewed to determine routine activities and professional competencies of PAs working in surgical pathology in Alberta, Manitoba, and Ontario. Interview transcripts were qualitatively analyzed to determine similarities and differences in job expectations, site requirements, and program learning objectives.

Results: There is strong consensus regarding minimum training, proficiencies, and continuing education expectations for PAs; however, descriptions of specific workplace duties and laboratory infrastructure vary across Alberta, Manitoba, and Ontario.

Conclusions: Disparities in scopes of practice for PAs across Alberta, Manitoba, and Ontario identified during interviews with program directors and PAs of MPA programs supports further research to elucidate these differences across a broader range of working Canadian PAs. Standardizing language and PA responsibilities will provide a basis for developing a national competency profile to define and increase recognition for this unique health care profession in Canada.

Back To Top

 

P711 Why wouldn’t we strip the fat? The Grace technique

Lance Fuczek.

Provincial Lead Pathologists’ Assistant, Diagnostic Services Manitoba, Department of Pathology, Pathologists’ Assistant Program, University of Manitoba.

Assessment of perinephric fat invasion is a crucial element of staging for Renal Cell Carcinoma. In general, recommended techniques for the assessment of the fat-renal capsule-tumour interface include cross sections through intact perinephric fat or examination after blunt dissection through fat outside the renal capsule. Both of these approaches result in relatively random sections and require that at least a component of perirenal fat remains attached to the specimen during fixation. The Grace “capsule stripping” technique involves the “stripping” of the renal capsule from the underlying kidney with careful gross assessment of the interior surface of the capsule. When utilizing this technique, tumour invading into capsule remains adherent to its inner surface. These areas of adhesion can be selectively sectioned to rule out perinephric fat invasion. Additional benefits of this technique are that kidney weight and dimension measurements are more accurate. It is our conclusion that this technique is superior to random sections through perinephric fat, and will be more likely to pick up areas of subtle perinephric invasion.

Back To Top

 

P712 Development of a Patient Information Sheet Regarding Surgical Pathology Fetal Examination

S. Cromwell1, A. Katz1, A. Martin1, F. Moid1,2.

1Pathology, Department of Laboratory Medicine, St. Joseph’s Health Centre, Toronto, Ontario.
2Department of Laboratory Medicine, University of Toronto, Toronto, Ontario.

Introduction: More frequently, parents are requesting to be informed of the details of fetal examinations that are performed for perinatal losses they have experienced at less than 20 weeks gestation. Reasons exist that may influence parental wishes regarding fetal examination, including religious beliefs, as well as lack of knowledge regarding the potential benefits that the performance of a fetal examination may provide, and a lack of understanding that desired limitations to examination that the parents may have can be accommodated. The provision of an information sheet prepared by the Pathology Department may provide helpful and valuable information to allow parents to make informed choices regarding the examination of their fetus subsequent to perinatal loss.

Methods: A review of the literature is conducted to obtain data to support the benefit of pathological fetal examination in the context of perinatal loss. Additionally, a variety of methods of patient information presentation are reviewed to allow for optimal patient engagement in the materials provided, with particular relevance to the reproductive age demographic.

Results: The literature demonstrates clear benefit to the performance of perinatal pathology examination for fetal losses, most prominently regarding confirmation and clarification of prenatal findings, and incorporation of findings in subsequent genetic counseling and future risk assessment. A FAQ oriented patient information sheet allows for exploration of potential parental questions and concerns about the surgical pathology examination of their infant, as well as providing the opportunity to request additional information using Hospital Social Workers as a conduit with Pathology.

Conclusion: Informed consent is facilitated by the provision of comprehensive patient information. A FAQ sheet for “Commonly Asked Questions” (currently for senior administrative health care centre assessment), has been developed to allow parents to have their enquiries about surgical pathology fetal examination addressed. The sheet will also enable parents to appreciate that they have control and choice over the degree of examination, if any, that is performed. The patient information sheet ultimately demonstrates that Pathology can be a constructive and active participant in important aspects of patient care.

Back To Top