Oral Presentations

Oral Presentations Session 1: Molecular Pathology and Biomarkers

 

1100-1115

Genetic Testing for Lynch syndrome in the Province of Ontario

Marina Wanga,b, Saud Aldubayanc,d, Ashton A. Connore,f,g, Beatrix Wonga, Kate Mcnamarae, Tahsin Khana, Kara Semotiukh, Sam Khaloueia,b, Spring Holtere,h, Melyssa Aronsone,h, Zane Cohene,h, Steve Gallingere,f,g,h, George Charamesa,b, Aaron Polletta,b, Jordan Lerner-Ellisa,b,f,h.

aPathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, ON; bLaboratory Medicine and Pathobiology, University of Toronto, Toronto, ON; cDepartment of Genetics, Harvard Medical School, Boston; dDepartment of Genetics and Genomics, Boston Children’s Hospital, Boston; eLunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON; fOntario Institute for Cancer Research, Toronto, ON; gDepartment of Surgery, Faculty of Medicine, University of Toronto, Toronto; hZane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, Toronto, Ontario.

Objective: We describe the outcomes of the genetic testing for Lynch syndrome (LS) program introduced by the Ontario Ministry of Health and Long-Term Care (MOH) in in 2001for individuals at high risk for LS cancers.

Methods: Testing was conducted from January 2001 to March 2015 at the molecular diagnostic laboratory at Mount Sinai Hospital in Toronto. Based on either tumour immunohistochemistry (IHC) staining or family history, subjects from a population at high-risk of LS were referred for molecular testing of the mismatch repair (MMR) genes MLH1, MSH2, and MSH6 if they met one of seven MOH criteria. Some subjects were tested for mutations in more than one MMR gene.

Data and Results: A total of 1452 subjects were tested. Of 662 subjects referred for testing because their tumour was immunodeficient for one or more of the MMR genes, 251 (37.9%) carried a germline mutation. Of those who underwent MLH1 testing, 25.6% had a mutation, of those who underwent MSH2 testing, 51.5% had a mutation, and of those who underwent MSH6 testing, 41.0% had a mutation.

Conclusions: These results indicate that the provincial criteria are useful in identifying LS carriers after an MMR deficient tumour is identified.

Keywords: Lynch syndrome, genetic testing, colorectal cancer, immunohistochemistry, microsatellite instability testing

 

1115-1130

Validation of Significant Prognostic Association of Hormone Receptor Expression with Survival In Ovarian Endometrioid Carcinoma, A Rationale For Hormonal Therapy

Peter Rambau (PR)1, Linda E. Kelemen2,3, Helen Steed4, Mary Lynn Quan5, Prafull Ghatage6, Martin Koebel1.

1Department of Pathology and Laboratory Medicine, University of Calgary, AB Canada; 2Department of Public Health Sciences, College of Medicine, Medical University of South Carolina, Charleston, SC, USA; 3Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA; 4Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada; 5Division of General Surgery and Surgical Oncology, University of Calgary, AB Canada; 6Department of Gynecological Oncology, Tom Baker Cancer Centre, University of Calgary, AB, Canada.

Objective: To validate whether hormone expression is associated with survival of women diagnosed with ovarian endometrioid carcinoma (EC) using the large, retrospective, population-based Alberta Ovarian tumor (AOVT) cohort with a histotype diagnosis confirmed by a diagnostic immunohistochemical marker panel.

Methods: Expression of estrogen (ER) and progesterone receptor (PR) was assessed on 182 EC samples represented on tissue microarrays. Statistical analyses were performed to test for associations with ovarian cancer specific survival.

Results: ER and PR expression was present in 87.3% and 86.7% of cases with co-expression present in 83.0% of cases. Hormonal receptor expression was higher in low grade and tumors with squamous differentiation. ER and PR expression were significantly associated with longer ovarian cancer specific survival (HR = 0.175 95% confidence interval 0.076-0.42, p=0.0002, HR=0.218, 95% confidence interval 0.096-0.527, p=0.0011, respectively) when adjusted for age, grade, treating center, stage and residual disease. However, in the group of interest (stage IC/II), the five year survival rate was not significantly different between ER expressing and negative cases (89.0% versus 76.1%, log rank p=0.0529).

Conclusion: Although we validated the prognostic value of hormone receptor expression in EC, it is unlikely of clinical utility to spare women diagnosed at stage IC/II from adjuvant therapy. However, our data provide further rationale for hormonal therapy in selected patients diagnosed with EC.

Keywords: Hormonal receptor expression, ovarian endometrioid carcinoma, survival

 

1130-1145

Association of p16 Expression with Prognosis Varies Across Ovarian Carcinoma Histotypes: An Ovarian Tumor Tissue Analysis Consortium Study

Peter F. Rambau (PR)1,2, Susan Ramus3, Michael Anglesio4, David Huntsman4, Martin Köbel1.

1Department of Pathology and Laboratory Medicine, University of Calgary, AB Canada; 2Department of Pathology, Catholic University of Health and Allied Sciences, Mwanza, Tanzania; 3University of New South Wales, Sydney, NSW, Australia; 4Department of Pathology and Laboratory Medicine, University of British Columbia, BC Cancer Agency, 600 West 10th Avenue, Vancouver, BC V5E 4E6, Canada.

Objective: P16 expression has been linked to prognosis in ovarian high-grade serous carcinoma. The purpose of this study was to validate prognostic association of p16 expression across different ovarian carcinoma histotypes.

Methods: p16 expression was assessed by immunohistochemistry on 4985 tumor samples; represented on tissue microarrays from 21 study sites participating in the Ovarian Tumor Tissue Analysis (OTTA) consortium. We recorded two abnormal expression patterns (block and absence of staining) and the normal (heterogeneous) pattern while applying a clinical grade assay and previously established staining pattern criteria. Survival analyses were performed by histotypes.

Data and Results: Block expression was highest in high-grade serous carcinoma (56%) compared to other types (1-15%). 93 of 620 patients diagnosed with clear cell carcinomas showing p16 block expression were associated with an increased risk of death (HR 1.62, 95% CI 1.17-2.20) in multivariate analysis. Absent expression was associated with indolent course in clear cell carcinoma (HR 0.67, 95% CI 0.46-0.96) but aggressive in low-grade serous carcinoma (HR 2.02, 95% CI 1.02-3.81). No significant associations were seen for high-grade serous, endometrioid and mucinous carcinomas.

Conclusion: The prognostic value of p16 expression is limited to clear cell and low-grade serous carcinoma with opposite effects suggesting a difference in the mechanisms underlying abnormal expression.

Keywords: ovarian carcinoma, p16, prognosis

 

1145-1200

Higher Expression of CDKN2A Gene is Potential Prognostic Marker for Clear Cell Renal Cell Carcinoma

Eriny Tawedrousa, Samantha Walaa,b, Rola Saleeba,b, Fabio Rotondoa, Qiang Dinga, George M Yousefa,b.

aDepartment of Laboratory Medicine, and the Keenan Research Centre for Biomedical Science at the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Ontario ; bDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Ontario.

Objective: We aim to investigate the expression of CDKN2A gene by immunohistochemistry and correlate its expression with the prognosis in clear cell renal cell carcinoma.

Methods: We investigated the prognostic value of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene expression, which is encoded on chromosome 9p21, in 294 primary ccRCC cases by immunohistochemistry on tissue microarray. We compared its expression with clinicopathologic parameters and patients’ survival. We also validated our results at the mRNA level on an independent set (415) from The Cancer Genome Atlas (TCGA).

Data and Results: There was a significant association between CDKN2A expression and tumor size, with higher expression associated with smaller tumor size (p < 0.001). As a dichotomous variable (positive vs. negative expression), there was a significant association between CDKN2A expression and tumor grade, with positive expression associated with lower tumor grades (p < 0.001). In the univariate analysis, positive expression was associated with significantly longer disease-free survival (HR= 0.46; p = 0.006). This was maintained in the multivariate analysis (HR= 0.44; p = 0.005). Kaplan-Meier survival analyses showed that positive CDKN2A expression was associated with statistically significant increase in disease-free survival (p = 0.007). We independently validated our results on 415 patients from the TCGA cohort which similarly showed a significant increase of the overall survival with higher CDKN2A expression levels (P = 0.04).

Conclusion: Our results indicated that CDKN2A is a potential prognostic marker for ccRCC that may give clinicians an extra tool to guide individual patient’s management.

Keywords: Kidney cancer, biomarkers, prognosis

 

1200-1215

Characterization of the Human Urinary Proteome and Peptidome

Ashley Di Meoa,b,c, Ihor Batruchb, Arsani G. Yousefb, Maria D. Pasicc,d, Eleftherios P. Diamandisb,c, George M. Yousefa,b,c.

aDepartment of Laboratory Medicine, and the Keenan Research Centre for Biomedical Science at the Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Canada. bDepartment of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Canada. cDepartment of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada. dDepartment of Laboratory Medicine, St. Joseph’s Health Centre, Toronto, Canada.

Objectives: To develop an integrated proteomic and peptidomic approach to characterize the normal urinary proteome and peptidome. To identify proteases involved in the generation of the endogenous peptide signature.

Methods: We performed label-free quantitative LC-MS/MS urine proteomic and peptidomic analysis on 6 healthy subjects that had no history of kidney-related or systemic disease. To identify proteases, the native urinary peptide signature was screened against a database that contains 3500 protease/cleavage site combinations of 191 proteases using Proteasix.

Data and Results: Our integrated analytical approach enabled identification of 1754 proteins and 4543 endogenous peptides, arising from 566 proteins in urine. We identified a total of 2091 non-redundant proteins. In silico protease activity analysis indicated that metalloproteases are predominantly involved in the generation of the endogenous peptide signature. MMP-9, -8, -12, -13 and -3 significantly contribute to the production of urinary peptides. Moreover, KLK2 and KLK6 were also found to contribute to the generation of the urine peptide signature.

Conclusion: Characterization of the normal urinary proteome and peptidome can provide insight into normal physiological processes and can be a basis for the discovery of non-invasive biomarkers in cancer. Employing an integrated proteomic and peptidomic approach allowed us to characterize a total of 2091 proteins with high-confidence. Our analysis provides one of the largest sets of protein identifications documented in normal human urine and provides a useful reference for disease biomarker discovery. Moreover, a thorough understanding of protease activity networks in normal physiology can offer insight into altered activity in disease.

Keywords: protease activity analysis, mass spectrometry, urinary peptidome, urinary proteome

 

1215-1230

Discrepancy in Detection of Anaplastic Lymphoma Kinase (ALK) Gene Status in Lung Cancer by Immunohistochemistry (IHC), and Fluor

Hemlata Shirsat, Weei-Yuarn Huang, Wenda Greer, Mathieu Castonguay, Zhaolin Xu.

Dalhousie University, Halifax, NS, Canada.

Background: Determination of anaplastic lymphoma kinase (ALK) gene status in lung cancer has become important in order to identify potential candidates for highly effective targeted chemotherapy. The gold standard test is fluorescent in situ hybridization (FISH). It is current practice in many centers using immunohistochemistry (IHC) as a screening test to examine ALK protein expression and use ALK FISH for confirmation of ALK gene rearrangement if IHC is positive or equivocal. Although the results of ALK IHC and FISH are consistent in general, the concordance is not 100% since the assays measure gene expression vs gene structure respectively.

Design: We examined all ALK results including ALK IHC (5A4 clone) and ALK FISH for lung cancer in our file in the last 3 years since the tests were implemented in the clinical setting to identify the discrepancy between IHC and FISH in order to determine the level of concordance in detecting ALK abnormalities.

Results: A total of 98 cases were subjected to both FISH and IHC. Four of these cases demonstrated discordance between IHC and FISH. Three cases which were positive, or weakly positive for ALK IHC were negative on FISH while one case which had negative result on IHC turned out to be positive for ALK gene rearrangement on FISH. All the IHC equivocal cases were FISH negative. One of the IHC positive FISH negative cases was further tested by RNA sequencing using next generation sequencing technology and was found to be positive for ALK gene rearrangement.

Conclusion: Discrepancy between IHC and FISH result is unusual but does exist. In such unusual circumstance further verification using different methods such as next generation sequencing should be applied.

Keywords: Anaplastic lymphoma kinase (ALK), Fluorescent in situ hybridization (FISH), Lung cancer, immunohistochemistry (IHC)

 

 

Oral Presentations Session 2: Pathology Education and QA

 

1100-1115

Developing, Implementing and Evaluating an Interactive Introduction to Laboratory Hematology Curriculum

Kathleen Wonga.

aDepartment of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada.

Objective: Resident evaluations of the 2014-2015 Joint Hematopathology and Hematology academic halfday program identified a need for a distinct introductory curriculum. My objective was to develop, implement and evaluate an Introduction to Laboratory Hematology curriculum that occurred July 2015. Goals were to provide a framework of core concepts and references, orient residents to laboratory hematology, and foster camaraderie and teamwork.

Method: The first session provided residents the curriculum plan with weekly objectives and references. Most sessions began with an individual or small group activity to facilitate active collaborative learning. Residents then engaged in facilitated discussions with content experts. Sessions concluded with case reviews to illustrate and consolidate concepts. During the final session, residents evaluated curricular content and teaching/learning methods with questionnaires using a 5-point Likert scale and free text comments.

Results: 13 residents participated, 6 from pathology (4 hematopathology; 2 general), and 7 from clinical hematology (5 adult; 2 pediatric fellows). 9 were junior residents with up to 3 months lab rotation experience. Residents found the content useful (4.83/5). They enjoyed the interactive teaching and active learning (4.54/5), and would like more case-based studies to enhance relevance and application to clinical and laboratory hematology practice (4.15/5).

Conclusions: The introductory curriculum oriented residents from different disciplines to the principles and practices of laboratory hematology through interactive teaching and active learning strategies. The template was used to build the first theme-based joint academic halfday program. Future iterations of the introductory curriculum will incorporate further opportunities for small group work through case-based studies.

Keywords: residency, education, curriculum development, innovation

 

1115-1130

Pathology Case Conferences: An Integrated Approach to Pathology Education for Third Year Medical Students

Matthew J. Cecchini1, David K. Driman1, Mariamma G. Joseph1.

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

Background and Objectives: At Western, pathology education for medical students is primarily focused on the first two pre-clerkship years to teach the pathological basis of disease. Clerkship and beyond is the time in training where students apply the fundamentals taught in years 1 and 2 to clinical situations. We identified a gap in pathology education during the clerkship year.

Methods: We developed a series of competencies in pathology that should be attained by the completion of medical school. To address these and increase the exposure of students to pathology in clerkship we developed an integrated teaching program. A series of ten modules were developed to cover diverse areas of pathology. A practical module was also developed to teach FNA biopsy techniques.

Results: All third year medical students had electronic access to the modules and spent 2-3 hours during their surgery rotations in the Department of Pathology, where they participated in small group discussions, practical demonstrations and had a tour of the department. Over the past 2 years, the program has had favorable reviews from both students and faculty involved in the project. In particular the students have found the practical approach to the teaching sessions and the FNA demonstrations beneficial.

Conclusion: The introductory curriculum oriented residents from different disciplines to the principles and practices of laboratory hematology through interactive teaching and active learning strategies. The template was used to build the first theme-based joint academic halfday program. Future iterations of the introductory curriculum will incorporate further opportunities for small group work through case-based studies.

Keywords: residency, education, curriculum development, innovation

 

1130-1145

Changing the Image of Pathology

Leslie M. Andersona.

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

Objective: Pathology has suffered from negative stereotypes and low interest in the specialty during the past few decades. This review examines how pathology has been previously perceived and discusses current and future efforts to change the image of pathology.

Methods: Through a literature review, media references, and discussion of various public relations campaigns and medical education initiatives, the stereotypes surrounding pathology and the efforts to change them are examined.

Data and Results: Pathologists have previously been stereotyped as eccentric and strange recluses, an image that has contributed to the low numbers of medical students choosing pathology as a career. Forensic pathologists are more commonly portrayed in the media than other types of pathologists, and are portrayed inaccurately, two factors that contribute further to misunderstanding of pathology as a specialty. To counteract these problems, more medical schools are providing exposure to pathology throughout the curriculum, various health organizations are creating awareness campaigns that seek to clarify the role pathology plays in health care, and increasing numbers of pathologists are participating in social media and leadership roles to engage with the public about what they do and how pathology impacts patients.

Conclusion: Negative stereotypes surrounding pathology are slowly changing and will continue to do so with current and future initiatives to change the image of pathology as a specialty.

Keywords: stereotypes, pathology, medical education, media

 

1145-1200

Implementation of a Peer to Peer Learning Initiative in Anatomical Pathology Residency Training

David Garcia-Marqueza, Matthew J. Cecchinia, Qi Zhanga.

aWestern University, London, Ontario, Canada.

Background and Objectives: Peer learning is the acquisition of knowledge through interactive teaching among individuals with equal levels of training. The participants are not professional teachers but through the process are able to enhance the learning of the group and solidify their own understanding of important concepts. It is not a substitute for formal teaching, but it is an important addition to the repertoire of learning activities.

Methods: We have organized peer learning rounds for the past 1.5 years. These rounds organized and attended by residents occur 2-3 days per week at the end of the day. Each resident contributes cases from their daily sign out so that all areas of Pathology have representation. The cases typically have important teaching points to share with the group. We have evaluated the success of the rounds through the distribution of a survey to the residents that have participated.

Results: Since its creation, we have seen over 761 cases from all areas of Pathology, presented by residents of all levels of training. We have scanned over 150 representative slides from the rounds that are stored in our own cataloged data base. There is consensus from participants that these rounds have provided a venue for continual exposure to diverse topics, discussion of complex subjects and to maintain camaraderie and communication between residents.

Conclusion: Peer to peer teaching is an effective adjunctive teaching modality that provides additional exposure to core pathology teaching concepts in an open and safe learning environment.

Keywords: medical education, peer to peer learning, Anatomical Pathology, Residents

 

1200-1215

Diagnostic Accuracy of Osmolal Gap, Anion Gap, and Acidosis for Methanol, Ethylene Glycol, and Isopropanol Testing In Calgary: A Review of Current Practice and Evaluation of Laboratory Predictors

Amy T. Thommasena, Dr. Christopher Nauglera,b, Dr. Mark Yaremac,d, Dr. Isolde Seiden-Longa.

aDepartment of Pathology and Laboratory Medicine, Cumming School of Medicine, University of Calgary, 3535 Research Rd NW, Calgary, Alberta, Canada, T2L 2K8; bDepartment of Family Medicine, Cumming School of Medicine, University of Calgary, Health Sciences Centre, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1; cPoison and Drug Information Service, Alberta Health Services, Foothills Medical Centre, 1403 29th St NW, Calgary, Alberta, Canada T2N 2T9; dDepartment of Emergency Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada, T2N 4N1.

Objective: Investigate (1) the diagnostic utility of osmolal gap (OGAP) as a screening test for serum methanol, ethylene glycol, and isopropanol exposure and (2) the effect of ethanol correction, anion gap (AGAP) and pH on the accuracy of OGAP.

Methods: All patient encounters where serum methanol, ethylene glycol, and isopropanol were ordered between January 2013 and June 2014 from 5 hospitals and 4 health centres in Calgary, Alberta, were collected. A correction coefficient for serum ethanol in OGAP was calculated by linear regression. The diagnostic accuracy of OGAP, serum pH and AGAP to identify patients with any detectable serum methanol, ethylene glycol, or isopropanol concentration was analyzed using sensitivity, specificity, odds ratio, multivariate receiver operator curves, and decision trees using SPSS software.

Data and Results: Seventy-nine of 886 encounters had detectable serum methanol, ethylene glycol, or isopropanol concentrations. A coefficient of 1.1 best corrected for ethanol contribution to measured serum osmolality. The resulting OGAP equation (OGAP = osmolalitymeasured – (2*sodium+glucose+UREA+Ethanol*1.1) had a sensitivity and specificity of 89% and 54%, respectively, above a threshold of ≥10. OGAP, serum ethanol, and arterial or venous pH had signifcant odds ratios to any detectable serum toxic alcohol. The area under the curve (AUC) for OGAP alone (AUC= 0.67) was improved by ethanol (AUC= 0.85) and ethanol and pH (AUC=0.91) (p<0.001 in all comparisons).

Conclusion: OGAP is a sensitive but non-specific test at a decision threshold of 10 that is improved by consideration of serum ethanol, AGAP and pH in evaluation of suspected toxic alcohol ingestion.

Keywords: osmolality, methanol, ethylene glycol, isopropanol, diagnosis

 

1215-1230

Breast Biopsy Case Selection for Prospective QA Review

Niloufar Hosseinia, Wedad Hannaa, Fang-I Lua, Guangming Hana, Sharon Nofech-Mozesa, Elzbieta Slodkowskaa.

aDepartment of Pathology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON.

Objectives: We recently introduced diagnostic breast coding (BC) for breast biopsies (BB) in our institution and aimed to investigate usefulness of this method in selection of BB for prospective QA review (PR).

Design: Recent BB in our institution are assigned a BC as follows (1:invasive mammary carcinoma, 2:DCIS, 3:LCIS, papilloma, FEL, any atypia, 4:benign 5:other) and all BC3 should undergo PR before sign-out. All in-house BB from Jan2014-Jul2015 were examined for adherence to abovementioned policy, PR rate in different BC, and distribution of BC in pathologists A to E. Rate of amended reports during this period was compared with Jan2009-Jul2010 period when PR of all BB was mandatory regardless of diagnosis.

Results: Of 2562 in-house BB, 2412(94.1%) were assigned BC. PR was performed on 606(23.6%) BB as follows: 49(7.6%)BC1, 50(31.2%)BC2, 270(87.9%)BC3, 182(14.1%)BC4 and 12(85.7%)BC5.BC distribution among pathologists is shown in Table1. Pathologist-C’s rates were skewed possibly due to low case volume. Differences in BC distribution are attributed to personal variation in coding. 15(0.6%) reports were amended, while for Jan2009-Jul2010 period there were 1639 BB of which 94.5% had PR and 12(0.7%) were amended.

A
N (%)
B
N (%)
C
N (%)
D
N (%)
E
N (%)
Mean
%
BC1 175 (25.6) 166(26.1) 21(16.5) 177(29.9) 143(28.6) 25.3
BC2 52 (7.6) 38(6.0) 15(11.8) 31(5.2) 32(6.4) 7.4
BC3 94 (13.7) 105(16.5) 16(12.6) 63(10.6) 39(7.8) 12.2
BC4 359 (52.5) 325(51.1) 74(58.3) 318(53.3) 282(56.4) 54.4
BC5 4 (0.6) 2(0.3) 1(0.8) 5(0.8) 4(0.8) 0.7
Total 684 636 127 594 500

Conclusion: BC is useful for selecting controversial cases for PR. It prevents PR of all BB without affecting amended reports rate.

Keywords: breast biopsy, diagnostic breast coding, prospective review, QA