Endometrial Pipelle Biopsy Computer-Aided Diagnosis: A Feasibility Study.

Endometrial biopsies are important in the diagnostic workup of women who present with abnormal uterine bleeding or hereditary risk of endometrial cancer. In general, approximately 10% of all endometrial biopsies demonstrate endometrial (pre)malignancy that requires specific treatment. As the diagnostic evaluation of mostly benign cases results in a substantial workload for pathologists, artificial intelligence (AI)-assisted preselection of biopsies could optimize the workflow. This study aimed to assess the feasibility of AI-assisted diagnosis for endometrial biopsies (endometrial Pipelle biopsy computer-aided diagnosis), trained on daily-practice whole-slide images instead of highly selected images. Endometrial biopsies were classified into 6 clinically relevant categories defined as follows: nonrepresentative, normal, nonneoplastic, hyperplasia without atypia, hyperplasia with atypia, and malignant. The agreement among 15 pathologists, within these classifications, was evaluated in 91 endometrial biopsies. Next, an algorithm (trained on a total of 2819 endometrial biopsies) rated the same 91 cases, and we compared its performance using the pathologist's classification as the reference standard. The interrater reliability among pathologists was moderate with a mean Cohen's kappa of 0.51, whereas for a binary classification into benign vs (pre)malignant, the agreement was substantial with a mean Cohen's kappa of 0.66. The AI algorithm performed slightly worse for the 6 categories with a moderate Cohen's kappa of 0.43 but was comparable for the binary classification with a substantial Cohen's kappa of 0.65. AI-assisted diagnosis of endometrial biopsies was demonstrated to be feasible in discriminating between benign and (pre)malignant endometrial tissues, even when trained on unselected cases. Endometrial premalignancies remain challenging for both pathologists and AI algorithms. Future steps to improve reliability of the diagnosis are needed to achieve a more refined AI-assisted diagnostic solution for endometrial biopsies that covers both premalignant and malignant diagnoses.

Recurrence rates and patterns of recurrence in stage IA p53abn endometrial cancer with and without myometrial invasion.

OBJECTIVES: Optimal management of patients with stage IA p53abn endometrial cancer without myoinvasion, classified as intermediate risk in the 2020 European Society of Gynaecological Oncology, European Society for Radiotherapy and Oncology, and European Society of Pathology (ESGO-ESTRO-ESP) guidelines, and the 2022 European Society of Medical Oncology (ESMO) guidelines, is currently unclear. Practice varies from surgery alone to adjuvant radiation±chemotherapy. Our aim was to assess the risk of disease recurrence in patients with stage IA p53abn endometrial cancer without myoinvasion compared with stage IA with myoinvasion (<50%). METHODS: Stage IA p53abn endometrial cancers were identified from retrospective cohorts. Cases were segregated into stage IA with no myoinvasion, including (1) tumor restricted to a polyp, (2) residual endometrial tumor, and (3) no residual tumor in hysterectomy specimen, versus stage IA p53abn with myoinvasion (<50%), with treatment and outcomes assessed. RESULTS: There were 65 stage IA p53abn endometrial cancers with no myoinvasion (22 polyp confined, 38 residual endometrial tumor, 2 no residual in hysterectomy specimen, 3 not specified) and 97 with myoinvasion. There was no difference in survival outcomes in patients with stage IA without myoinvasion (16% of patients recurred, 19% if there was residual endometrial disease) compared with stage IA with myoinvasion (17%). The risk of recurrence was lowest in patients with stage IA p53abn endometrial cancer without myoinvasion treated with chemotherapy±radiation (8%). Most recurrences in patients with stage IA without myoinvasion were distant (89%), with no isolated vaginal vault recurrences, and all except one distant recurrence occurred in patients who had not received adjuvant chemotherapy. CONCLUSION: The recurrence rate in patients with stage IA p53abn endometrial cancer without myoinvasion was 16%, highest in the setting of residual endometrial disease (19%), and exceeding the threshold where adjuvant therapy is often considered. The high frequency of distant recurrences observed may support chemotherapy as part of the treatment regimen.

Increased FOXJ1 protein expression is associated with improved overall survival in high-grade serous ovarian carcinoma: an Ovarian Tumor Tissue Analysis Consortium Study.

BACKGROUND: Recently, we showed a >60% difference in 5-year survival for patients with tubo-ovarian high-grade serous carcinoma (HGSC) when stratified by a 101-gene mRNA expression prognostic signature. Given the varied patient outcomes, this study aimed to translate prognostic mRNA markers into protein expression assays by immunohistochemistry and validate their survival association in HGSC. METHODS: Two prognostic genes, FOXJ1 and GMNN, were selected based on high-quality antibodies, correlation with protein expression and variation in immunohistochemical scores in a preliminary cohort (n = 134 and n = 80, respectively). Six thousand four hundred and thirty-four (FOXJ1) and 5470 (GMNN) formalin-fixed, paraffin-embedded ovarian neoplasms (4634 and 4185 HGSC, respectively) represented on tissue microarrays from the Ovarian Tumor Tissue Analysis consortium underwent immunohistochemical staining and scoring, then univariate and multivariate survival analysis. RESULTS: Consistent with mRNA, FOXJ1 protein expression exhibited a linear, increasing association with improved overall survival in HGSC patients. Women with >50% expression had the most favourable outcomes (HR = 0.78, 95% CI 0.67-0.91, p < 0.0001). GMNN protein expression was not significantly associated with overall HSGC patient survival. However, HGSCs with >35% GMNN expression showed a trend for better outcomes, though this was not significant. CONCLUSION: We provide foundational evidence for the prognostic value of FOXJ1 in HGSC, validating the prior mRNA-based prognostic association by immunohistochemistry.

p53-Abnormal "Fields of Dysplasia" in Human Papillomavirus-Independent Vulvar Squamous Cell Carcinoma Impacts Margins and Recurrence Risk.

Abnormal p53 (p53abn) immunohistochemical (IHC) staining patterns can be found in vulvar squamous cell carcinoma (VSCC) and differentiated vulvar intraepithelial neoplasia (dVIN). They can also be found in the adjacent skin that shows morphology that falls short of the traditional diagnostic threshold for dVIN. Vulvectomy specimens containing human papillomavirus-independent p53abn VSCC with margins originally reported as negative for invasive and in situ disease were identified. Sections showing the closest approach by invasive or in situ neoplasia to margins were stained with p53 IHC stains. We evaluated the following: (1) detection of morphologically occult p53abn in situ neoplasia, (2) rates of margin status change after p53 IHC staining, and (3) effect of p53abn IHC staining at margins on the 2-year local recurrence rates. Seventy-three human papillomavirus-independent p53abn VSCCs were included. Half (35/73, 48%) had documented an in situ lesion in the original report. The use of p53 IHC staining identified 21 additional cases (29%) with the p53abn in situ lesions that were originally unrecognized. The histology of in situ lesions in the p53abn "field" varied and became more subtle (morphologically occult) farther away from the VSCC. Fifteen (21%) cases had a morphologically occult and previously unrecognized p53abn in situ lesion present at a resection margin, which conferred an increased risk of local recurrence (5/7 [71.4%] vs 6/22 [27.3%], P = .036). The p53abn in situ lesions at a margin were confirmed to have TP53 mutations by sequencing. p53 IHC staining identified morphologically occult p53abn in situ lesions surrounding human papillomavirus-independent VSCC. p53abn IHC staining at a margin was associated with a 3-fold increased risk of local recurrence.

Classification of Vulvar Squamous Cell Carcinoma and Precursor Lesions by p16 and p53 Immunohistochemistry: Considerations, Caveats, and an Algorithmic Approach.

There is emerging evidence that vulvar squamous cell carcinoma (VSCC) can be prognostically subclassified into 3 groups based on human papillomavirus (HPV) and p53 status: HPV-associated (HPV+), HPV-independent/p53 wild-type (HPV-/p53wt), or HPV-independent/p53 abnormal (HPV-/p53abn). Our goal was to assess the feasibility of separating VSCC and its precursors into these 3 groups using p16 and p53 immunohistochemistry (IHC). A tissue microarray containing 225 VSCC, 43 usual vulvar intraepithelial neoplasia (uVIN/HSIL), 10 verruciform acanthotic vulvar intraepithelial neoplasia (vaVIN), and 34 differentiated VIN (dVIN), was stained for p16 and p53. Noncomplementary p16 and p53 patterns were resolved by repeating p53 IHC and HPV RNA in situ hybridization (ISH) on whole sections, and sequencing for TP53. Of 82 p16-positive VSCC, 73 (89%) had complementary p16 and p53 patterns and were classified into the HPV+ group, 4 (4.9%) had wild-type p53 staining, positive HPV ISH and were classified into the HPV+ group, whereas 5 (6.1%) had p53 abnormal IHC patterns (1 null, 4 overexpression), negativity for HPV ISH, and harbored TP53 mutations (1 splice site, 4 missense); they were classified as HPV-/p53abn. Of 143 p16-negative VSCC, 142 (99.3%) had complementary p53 and p16 patterns: 115 (80.4%) HPV-/p53abn and 27 (18.9%) HPV-/p53wt. One had a basal-sparing p53 pattern, positivity for HPV ISH and was negative for TP53 mutations-HPV+ category. The use of IHC also led to revised diagnoses-HSIL to dVIN (3/43), dVIN to vaVIN (8/34), and dVIN to HSIL (3/34). Overall, 215/225 VSCC (95.6%) could be easily classifiable into 3 groups with p16 and p53 IHC. We identified several caveats, with the major caveat being that "double-positive" p16/p53 should be classified as HPV-/p53abn. We propose an algorithm that will facilitate the application of p16 and p53 IHC to classify VSCC in pathology practice.

Profiling the immune landscape in mucinous ovarian carcinoma.

OBJECTIVE: Mucinous ovarian carcinoma (MOC) is a rare histotype of ovarian cancer, with low response rates to standard chemotherapy, and very poor survival for patients diagnosed at advanced stage. There is a limited understanding of the MOC immune landscape, and consequently whether immune checkpoint inhibitors could be considered for a subset of patients. METHODS: We performed multicolor immunohistochemistry (IHC) and immunofluorescence (IF) on tissue microarrays in a cohort of 126 MOC patients. Cell densities were calculated in the epithelial and stromal components for tumor-associated macrophages (CD68+/PD-L1+, CD68+/PD-L1-), T cells (CD3+/CD8-, CD3+/CD8+), putative T-regulatory cells (Tregs, FOXP3+), B cells (CD20+/CD79A+), plasma cells (CD20-/CD79a+), and PD-L1+ and PD-1+ cells, and compared these values with clinical factors. Univariate and multivariable Cox Proportional Hazards assessed overall survival. Unsupervised k-means clustering identified patient subsets with common patterns of immune cell infiltration. RESULTS: Mean densities of PD1+ cells, PD-L1- macrophages, CD4+ and CD8+ T cells, and FOXP3+ Tregs were higher in the stroma compared to the epithelium. Tumors from advanced (Stage III/IV) MOC had greater epithelial infiltration of PD-L1- macrophages, and fewer PD-L1+ macrophages compared with Stage I/II cancers (p = 0.004 and p = 0.014 respectively). Patients with high epithelial density of FOXP3+ cells, CD8+/FOXP3+ cells, or PD-L1- macrophages, had poorer survival, and high epithelial CD79a + plasma cells conferred better survival, all upon univariate analysis only. Clustering showed that most MOC (86%) had an immune depleted (cold) phenotype, with only a small proportion (11/76,14%) considered immune inflamed (hot) based on T cell and PD-L1 infiltrates. CONCLUSION: In summary, MOCs are mostly immunogenically 'cold', suggesting they may have limited response to current immunotherapies.

A Multiplex SNaPshot Assay is a Rapid and Cost-Effective Method for Detecting POLE Exonuclease Domain Mutations in Endometrial Carcinoma.

Determining the replicative DNA polymerase epsilon ( POLE) mutation status in endometrial carcinomas (ECs) has important clinical implications given that the majority of "ultramutated" tumors harboring pathogenic exonuclease domain mutations in POLE ( POLE mut) have a favorable prognosis, even among high-grade histotypes. Currently, there are no specific morphologic or immunophenotypic features that allow accurate detection of POLE mut tumors without molecular testing. Consequently, identifying POLE mut tumors has been challenging without employing costly and/or time-consuming DNA sequencing approaches. Here we developed a novel SNaPshot assay to facilitate routine and efficient POLE mutation testing in EC. The SNaPshot assay interrogates 15 nucleotide sites within exons 9, 11, 13, and 14 encoding the POLE exonuclease domain. The variant sites were selected based on recurrence, evidence of functional impact, association with high tumor mutation burden and/or detection in EC clinical outcome studies. Based on the pathogenic somatic variants reported in the literature, the assay is predicted to have a clinical sensitivity of 90% to 95% for ECs. Validation studies showed 100% specificity and sensitivity for the variants covered, with expected genotypic results for both the positive (n=11) and negative (n=20) patient controls on multiple repeat tests and dilution series. Analytic sensitivity was conservatively approximated at a 10% variant allele fraction (VAF), with documented detection as low as 5% VAF. As expected, the SNaPshot assay demonstrated greater sensitivity than Sanger sequencing for VAFs below 20%, an important characteristic for somatic mutation detection. Here we have developed and validated the first SNaPshot assay to detect hotspot POLE mutations. While next-generation sequencing and Sanger sequencing-based approaches have also been used to detect POLE mutations, a SNaPshot approach provides useful balance of analytical sensitivity, cost-effectiveness, and efficiency in a high-volume case load setting.

Performance of a HER2 testing algorithm specific for p53-abnormal endometrial cancer.

AIMS: Human epidermal growth factor receptor 2 (HER2) amplification in endometrial cancer (EC) is almost completely confined to the p53-abnormal (p53abn) molecular subtype and independent of histological subtype. HER2 testing should therefore be molecular subtype-directed. However, the most optimal approach for HER2 testing in EC has not been fully established. Therefore, we developed an EC-specific HER2 immunohistochemistry (IHC) scoring method and evaluated its reproducibility and performance to establish an optimal diagnostic HER2 testing algorithm for p53abn EC. METHODS AND RESULTS: HER2 IHC slides of 78 p53abn EC were scored by six gynaecopathologists according to predefined EC-specific IHC scoring criteria. Interobserver agreement was calculated using Fleiss' kappa and the first-order agreement coefficient (AC1). The consensus IHC score was compared with HER2 dual in-situ hybridisation (DISH) results. Sensitivity and specificity were calculated. A substantial interobserver agreement was found using three- or two-tiered scoring [κ = 0.675, 95% confidence interval (CI) = 0.633-0.717; AC1 = 0.723, 95% CI = 0.643-0.804 and κ = 0.771, 95% CI = 0.714-0.828; AC1 = 0.774, 95% CI = 0.684-0.865, respectively]. Sensitivity and specificity for the identification of HER2-positive EC was 100 and 97%, respectively, using a HER2 testing algorithm that recommends DISH in all cases with moderate membranous staining in >10% of the tumour (IHC+). Performing DISH on all IHC-2+ and -3+ cases yields a sensitivity and specificity of 100%. CONCLUSIONS: Our EC-specific HER2 IHC scoring method is reproducible. A screening strategy based on IHC scoring on all cases with subsequent DISH testing on IHC-2+/-3+ cases has perfect test accuracy for identifying HER2-positive EC.

Targeted Molecular Sequencing of Recurrent and Multifocal Non-HPV-associated Squamous Cell Carcinoma of the Vulva.

Recurrent vulvar squamous cell carcinomas (SCCs) are a poorly understood and aggressive group of treatment-resistant neoplasms. Currently, it remains unclear whether these are in fact recurrences of the same primary tumor, or the development of entirely new tumors. Here, to address this question, we examined the mutational profile of a series of patients with recurrent or multifocal non-human papilloma virus (HPV)-associated vulvar SCC. We performed a targeted 33-gene next-generation sequencing panel on a series of 14 patients with recurrent or multifocal non-HPV-associated vulvar SCC and precursor neoplasms. This amounted to 54 cases (33 SCC, 1 verrucous carcinoma, 13 differentiated vulvar intraepithelial neoplasia, and 7 differentiated exophytic vulvar intraepithelial lesion), with 79 mutations detected altogether. TP53 [51/79 (65%)] was the most frequently mutated gene. Mutations in PIK3CA [16/79 (20%)), HRAS [6/79 (8%)], PTEN [4/79 (5%)], EGFR [1/79 (1%)], and GNAS [1/79 (1%)] were occasionally seen. Most patients with SCC [5/9 (56%)] recurrent, 4/5 (80%) multifocal] demonstrated a clonal relationship, and harbored the same mutations in the same genes in metachronous or synchronous tumors. A subset of the recurrent tumors [2/5 (40%)] recurred with additional mutations. These clonal relationships were shared between SCC and differentiated vulvar intraepithelial neoplasia in each case. By contrast, a small number of recurrent tumors [3/9 (33%)] demonstrated novel mutations, entirely different from the primary tumor. Thus, our findings suggest that recurrent non-HPV-associated vulvar SCC can arise from 2 mechanisms.

International Endocervical Adenocarcinoma Criteria and Classification (IECC): An Independent Cohort With Clinical and Molecular Findings.

Recently, the International Endocervical Adenocarcinoma Criteria and Classification (IECC) has reorganized the classification of endocervical adenocarcinomas (ECAs), separating them into human papilloma virus (HPV)-associated (HPVA) and HPVA independent (HPVI) categories. In this study, we sought to revalidate the IECC clinical findings in an independent cohort and assess the mutational differences between HPVA and HPVI ECAs using next generation sequencing. Consecutive cases of ECAs were reclassified under the IECC. Clinicopathologic information was collected and tissue was sent for targeted next-generation sequencing in 33 genes. Associations between HPV status, clinicopathologic parameters and mutation status, with survival were evaluated. The series comprised of 85/100 HPVA (63 HPVA-usual type, 4 villoglandular, 3 mucinous intestinal, 15 mucinous not otherwise specified) and 15/100 HPVI (9 gastric, 4 mesonephric, 1 clear cell, 1 not otherwise specified). HPVA ECAs presented at a lower age (P=0.001), smaller tumor sizes (P=0.011), less margin positivity (P=0.027), less Silva pattern C (P=0.002), and lower FIGO stages (P=0.020). HPVA had superior survival compared with HPVI ECA [overall survival (P=0.0026), disease-specific survival (P=0.0092), and progression-free survival (P=0.0041)]. Factors that correlated with worse prognosis irrespective of HPV status were FIGO stage, positive margins and lymphovascular invasion (P<0.05). TP53 mutations were detected in a significantly higher proportion of HPVIs than HPVAs (P<<0.001). The study revalidates the IECC system by reaffirming the clinical and prognostic differences between HPVA and HPVI ECAs in an independent dataset.

SATB2 Expression in Uterine Sarcoma: A Multicenter Retrospective Study.

Uterine sarcomas represent a clinical challenge because of their difficult diagnosis and the poor prognosis of certain subtypes. The aim of this study was to evaluate the expression of the special AT-rich sequence-binding protein 2 (SATB2) in endometrial stromal sarcoma (ESS) and other types of uterine sarcoma by immunohistochemistry. We studied the expression of SATB2 on 71 full tissue sections of endometrial stromal nodule, low-grade ESS, uterine leiomyomas and leiomyosarcoma, undifferentiated uterine sarcoma, adenosarcoma, and carcinosarcoma samples. Nuclear SATB2 expression was then evaluated in an extended sample set using a tissue microarray, including 78 additional uterine tumor samples. Overall, with a cut-off of ≥10% of tumor cell staining as positive, the nuclear SATB2 score was negative in all endometrial stromal nodule samples (n=10) and positive in 83% of low-grade ESS samples (n=29/35), 40% of undifferentiated uterine sarcoma (n=4/10), 13% of leiomyosarcoma (n=2/16), 14% of adenosarcoma (n=3/22), and 8% carcinosarcoma (n=2/25) samples. Furthermore, in ESS patients, direct comparison of nuclear SATB2 scores with clinicopathologic parameters and other reported biomarkers such as progesterone receptor and estrogen receptor showed that nuclear SATB2 was associated with PR expression and a decreased risk of disease-specific death (odds ratio=0.06, 95% confidence interval=0.04-0.81, P=0.04). Our data suggest that SATB2 could be a marker with relative sensitivity (83%) for distinguishing between endometrial stromal nodule and ESS with potential prognostic value.

Use of Immunohistochemical Markers (HNF-1ß, Napsin A, ER, CTH, and ASS1) to Distinguish Endometrial Clear Cell Carcinoma From Its Morphologic Mimics Including Arias-Stella Reaction.

The diagnosis of clear cell (CC) carcinoma of the endometrium can be challenging, especially when endometrioid (EC) and serous (SC) endometrial cancers exhibit nonspecific clear cell changes, in carcinomas with mixed histology and in the setting of Arias-Stella reaction (ASR). In this study, classic CC immunohistochemical markers (Napsin A, HNF-1ß, and ER) and 2 recent novel markers, cystathionine gamma-lyase (CTH) and arginosuccinate synthase (ASS1), are assessed for their utility in distinguishing CC from its morphologic mimics. Tissue microarrays containing 64 CC, 128 EC, 5 EC with clear cell change, 16 SC, 5 mixed carcinomas, and 11 whole ASR sections were stained, with 12 additional examples of ASR stained subsequently. A cutoff of 70% and moderate intensity were used for HNF-1ß, 80% of cells and strong intensity were used for CTH, and any staining was considered positive for the remaining markers. For differentiating CC from pure EC and SC, HNF-1ß, Napsin A, and CTH all performed well. HNF-1ß had higher specificity (99.3% vs. 95.1%) but lower sensitivity (55.8% vs. 73.1%) compared with Napsin A. CTH did not substantially outperform HNF- 1ß or Napsin A (sensitivity 51.9%, specificity 99.3%). ASS1 and ER were not helpful (specificities of 60.1% and 22.6%). For differentiating CC from ASR, HNF-1ß, Napsin A, and CTH stained a large proportion of ASR and were not useful. However, ER positivity and ASS1 negativity were helpful for identifying ASR (specificity 88.2% and 95.1%, respectively). EC with clear cell changes exhibited immunohistochemical patterns similar to pure EC (HNF-1ß-, ER+, and CTH-). No markers were useful in confirming the CC components in mixed carcinomas.

Oncogenic mutations in histologically normal endometrium: the new normal?

The advent of next generation sequencing has vastly improved the resolution of mutation detection, thereby both increasing the resolution of the analysis of cancer tissues and shining light on the existence of somatic driver mutations in normal tissues, even in the absence of cancer. Studies have described somatic driver mutations in normal skin, blood, peritoneal washings, and esophageal epithelium. Such findings prompt speculation on whether such mutations exist in other tissues, such as the eutopic endometrium in particular, due to the highly regenerative nature of the endometrium and the recent observation of recurrent somatic driver mutations in deep infiltrating and iatrogenic endometriosis (tissues believed to be derived from the eutopic endometrium) by our group and others. In the current study we investigated the presence of somatic driver mutations in histologically normal endometrium from women lacking evidence of gynecologic malignancy or endometrial hyperplasia. Twenty-five women who underwent hysterectomies and 85 women who underwent endometrial biopsies were included in this study. Formalin-fixed, paraffin-embedded tissue specimens were analyzed by means of targeted sequencing followed by orthogonal validation with droplet digital PCR. PTEN and ARID1A immunohistochemistry (IHC) was also performed as surrogates for inactivating mutations in the respective genes. Overall, we observed somatic driver-like events in over 50% of normal endometrial samples analyzed, including hotspot mutations in KRAS, PIK3CA, and FGFR2 as well as PTEN-loss by IHC. Analysis of anterior and posterior samplings collected from women who underwent hysterectomies was consistent with the presence of somatic driver mutations within clonal pockets spread throughout the uterus. The prevalence of such oncogenic mutations also increased with age (OR: 1.05 [95% CI: 1.00-1.10], p = 0.035). These findings have implications on our understanding of aging and so-called 'normal tissues', thereby necessitating caution in the utilization of mutation-based early detection tools for endometrial or other cancers. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Mismatch repair deficiency and prognostic significance in patients with low-risk endometrioid endometrial cancers.

OBJECTIVES: Mismatch repair deficiency is observed in 25%-30% of all endometrial cancers. This can be detected by the absence of mismatch repair protein staining on immunohistochemistry, and is used as a screen for Lynch syndrome. Only 10% of women with mismatch repair deficiency have Lynch syndrome, but mismatch repair deficiency may still have prognostic significance. The objective of this study was to compare clinical outcomes between mismatch repair-deficient and mismatch repair-proficient low-risk endometrioid endometrial cancers (stage IA, grade 1 or 2). METHODS: This was a retrospective population-based cohort study of all low-risk endometrioid endometrial cancers (stage IA, grade 1 or 2) from the Vancouver Coastal Health Authority region from February 2011 to January 2016 that were assessed for mismatch repair deficiency. Any other histology, stage, or grade was excluded from the study. Primary outcome measures were progression-free survival and overall survival calculated using Kaplan-Meier method and log-rank tests. Cox proportional hazards model estimated the association between mismatch repair deficiency and recurrence and death after adjustment for covariates, expressed as hazard ratios (HRs). Secondary outcome measures were recurrence rates expressed per 100 person-years (p100py). RESULTS: There were 475 patients diagnosed with low-risk endometrioid endometrial cancer, including 131 with mismatch repair-deficient (27.6%) and 344 with mismatch repair-proficient (72.4%) tumors. Women with mismatch repair-deficient tumors had worse progression-free survival (24 months; p=0.0082) and higher recurrence rates (3.56 p100py) compared with those with mismatch repair-proficient tumors (27 months; 1.21 p100py, p=0.04). The absolute number of recurrences was overall low. There were 11 recurrences out of 131 mismatch repair-deficient cases (8.4%) and 14 out of 344 mismatch repair proficient cases (4.1%). After adjustment for age, lymphovascular space invasion status, adjuvant therapy, and post-operative grade, mismatch repair-deficient status remained associated with a higher risk of recurrence (HR 3.56, 95% CI 2.01 to 5.95). There was no significant difference in overall survival between mismatch repair groups (mismatch repair-proficient group 27.5 months vs 25.0 months in the deficient group) (HR 1.23, 95% CI 0.49 to 3.10). CONCLUSION: In low-risk stage IA grade 1 or 2 endometrioid endometrial cancers, mismatch repair deficiency is associated with a higher recurrence rate than mismatch repair proficiency after adjustment for covariates, implying that mismatch repair deficiency reflects a different biology in endometrial cancer.

Association of human papilloma virus status and response to radiotherapy in vulvar squamous cell carcinoma.

INTRODUCTION: Vulvar squamous cell carcinoma develops through two separate pathways, associated with the presence or absence of high-risk human papilloma virus (HPV). The objective of this study was to evaluate treatment response and clinical outcomes in women with HPV-associated versus HPV-independent vulvar squamous cell carcinoma treated with primary radiation therapy, in order to determine the ability to use HPV status as a predictor of response to radiation therapy. METHODS: This was a retrospective cohort study combining data from British Columbia Cancer, Canada and Duke University, USA. Patients were included who had been treated with radiation therapy but excluded if they had received major surgical interventions. Immunohistochemistry for p16 (as a surrogate for high-risk HPV infection) and p53 was performed. We analyzed the univariable association between p16 status and clinico-pathological features and performed univariable survival analysis for p16. RESULTS: Forty-eight patients with vulvar squamous cell carcinoma treated with primary radiation therapy were identified: 26 p16 positive/HPV-associated patients and 22 p16 negative/HPV-independent patients. p16 positive vulvar squamous cell carcinoma demonstrated a significantly improved overall survival (HR 0.39, p=0.03) and progression-free survival (HR 0.35, p=0.02). In women treated with definitive radiation therapy, p16 positivity was associated with improved overall survival (HR 0.29, p<0.01) and progression-free survival (HR 0.21, p<0.01). Among patients who received sensitizing chemotherapy, a significant association was observed with p16 positive tumors and overall survival (HR 0.25, p=0.03) and progression-free survival (HR 0.09, p<0.01). CONCLUSION: This study suggests that HPV status in vulvar squamous cell carcinoma has both prognostic and predictive implications, with increased radiosensitivity demonstrated in HPV-associated vulvar squamous cell carcinoma. Implications may include radiation dose de-escalation for HPV-associated vulvar squamous cell carcinoma and increased surgical aggressiveness for HPV-independent vulvar squamous cell carcinoma.

Histopathologic response to neoadjuvant chemotherapy as a prognostic biomarker in tubo-ovarian high-grade serous carcinoma: updated Chemotherapy Response Score (CRS) results.

OBJECTIVE: The Chemotherapy Response Scoring (CRS) system was developed to enable reproducible reporting of histologic tumor response in interval debulking specimens following neoadjuvant chemotherapy in advanced stage tubo-ovarian high-grade serous carcinoma. This prognostic biomarker has been included in ovarian cancer pathology reporting guidelines (International Collaboration on Cancer Reporting, College of American Pathologists) and in the upcoming European Society for Medical Oncology-European Society of Gynaecological Oncology (ESMO-ESGO) guidelines for ovarian cancer management. We present follow-up data on the CRS validation initiatives and suggest research with novel therapeutic agents incorporating this biomarker. METHODS: The cohort on whom CRS was originally developed was analyzed after an extended follow-up of an additional 36 months. The CRS histopathologic scoring system was applied to omental sections obtained at interval surgery from all 80 patients. Progression-free and overall survival were re-calculated. RESULTS: After a median follow-up of 4.3 years the CRS score predicted progression-free survival with an HR of 0.39 (95% CI 0.21 to 0.70), p = 0.002 adjusted for age, stage, and debulking status (median 1.08 vs 2.27 years for CRS1/2 vs CRS3). CRS was also predictive of overall survival with an HR of 0.17 (95% CI 0.07 to 0.44), p = 0.0002 adjusted for age, stage, and debulking status (median 2.55 vs 5.47 years for CRS1/2 vs CRS3). CONCLUSION: CRS3 is a reproducible prognostic biomarker for improved progression-free and overall survival in stage 3C or 4 tubo-ovarian high-grade serous carcinoma after neoadjuvant chemotherapy. The score, obtained at interval debulking surgery, can help facilitate research and biomarker driven first-line treatment of patients with advanced ovarian cancer.

Candidate biomarkers of PARP inhibitor sensitivity in ovarian cancer beyond the BRCA genes.

BACKGROUND: Olaparib (Lynparza™) is a PARP inhibitor approved for advanced BRCA-mutated (BRCAm) ovarian cancer. PARP inhibitors may benefit patients whose tumours are dysfunctional in DNA repair mechanisms unrelated to BRCA1/2. We report exploratory analyses, including the long-term outcome of candidate biomarkers of sensitivity to olaparib in BRCA wild-type (BRCAwt) tumours. METHODS: Tumour samples from an olaparib maintenance monotherapy trial (Study 19, D0810C00019; NCT00753545) were analysed. Analyses included classification of mutations in genes involved in homologous recombination repair (HRR), BRCA1 promoter methylation status, measurement of BRCA1 protein and Myriad HRD score. RESULTS: Patients with BRCAm tumours gained most benefit from olaparib; a similar treatment benefit was also observed in 21/95 patients whose tumours were BRCAwt but had loss-of-function HRR mutations compared to patients with no detectable HRR mutations (58/95). A higher median Myriad MyChoice® HRD score was observed in BRCAm and BRCAwt tumours with BRCA1 methylation. Patients without BRCAm tumours derived benefit from olaparib treatment vs placebo although to a lesser extent than BRCAm patients. CONCLUSIONS: Ovarian cancer patients with tumours harbouring loss-of-function mutations in HRR genes other than BRCA1/2 may constitute a small, molecularly identifiable and clinically relevant population who derive treatment benefit from olaparib similar to patients with BRCAm.

Characteristics and outcome of the COEUR Canadian validation cohort for ovarian cancer biomarkers.

BACKGROUND: Ovarian carcinoma is the most lethal gynecological malignancy due to early dissemination and acquired resistance to platinum-based chemotherapy. Reliable markers that are independent and complementary to clinical parameters are needed to improve the management of patients with this disease. The Canadian Ovarian Experimental Unified Resource (COEUR) provides researchers with biological material and associated clinical data to conduct biomarker validation studies. Using standards defined by the Canadian Tissue Repository Network (CTRNet), we have previously demonstrated the quality of the biological material from this resource. Here we describe the clinical characteristics of the COEUR cohort. METHODS: With support from 12 Canadian ovarian cancer biobanks in Canada, we created a central retrospective cohort comprised of more than 2000 patient tissue samples with associated clinical data, including 1246 high-grade serous, 102 low-grade serous, 295 endometrioid, 259 clear cell and 89 mucinous carcinoma histotypes. A two-step reclassification process was applied to assure contemporary histological classification (histotyping). For each histotypes individually, we evaluated the association between the known clinico-pathological parameters (stage, cytoreduction, chemotherapy treatment, BRCA1 and BRCA2 mutation) and patient outcome by using Kaplan-Meier and Cox proportional hazard regression analyses. RESULTS: The median follow-up time of the cohort was 45 months and the 5-year survival rate for patients with high-grade serous carcinomas was 34%, in contrast to endometrioid carcinomas with 80% at 5 years. Survival profiles differed by histotype when stratified by stage or cytoreduction. Women with mucinous or clear cell carcinomas at advanced stage or with non-optimally debulked disease had the worst outcomes. In high-grade serous carcinoma, we observed significant association with longer survival in women harboring BRCA1 or BRCA2 mutation as compared to patients without detectable mutation. CONCLUSIONS: Our results show the expected survival rates, as compared with current literature, in each histotype suggesting that the cohort is an unbiased representation of the five major histotypes. COEUR, a one stop comprehensive biorepository, has collected mature outcome data and relevant clinical data in a comprehensive manner allowing stratified analysis.

Hereditary Breast and Ovarian Cancer Syndrome: Moving Beyond BRCA1 and BRCA2.

The recent implementation of next generation sequencing and multigene platforms has expanded the spectrum of hereditary breast and ovarian cancer syndrome, beyond the traditional genes BRCA1 and BRCA2. A large number of other moderate penetrance genes have now been uncovered, which also play critical roles in repairing double stranded DNA breaks through the homologous recombination pathway. This review discusses the landmark discoveries of BRCA1 and BRCA2, the homologous repair pathway and new genes discovered in hereditary breast and ovarian cancer syndrome, as well as their clinicopathologic significance and implications for genetic testing. It also highlights the new role of PARP inhibitors in the context of synthetic lethality and prophylactic surgical options.

Endometrial Cancer Presentation and Outcomes Based on Mismatch Repair Protein Expression From a Population-Based Study.

OBJECTIVE: There is uncertainty about the prognostic significance of mismatch repair (MMR) deficiency in endometrial cancer. The objective was to evaluate clinical characteristics and outcomes of endometrial cancers based on MMR status within a population-based study. METHODS: This was a retrospective population-based cohort study of all endometrial cancer cases from the Vancouver Coastal Health Authority region, evaluated for 4 MMR proteins using immunohistochemistry from 2012 to 2015. Patients were classified as MMR deficient (dMMR, any MMR protein absent) or MMR proficient (pMMR), Demographics, tumor characteristics, recurrences, and survival rates were compared according to MMR status. RESULTS: There were 892 patients, with 650 pMMR (72.5%) and 242 dMMR tumors. The dMMR group had more endometrioid tumors (87.6% vs 74.0%, P < 0.001), lymphovascular space invasion (43.8% vs 30.8%, P = 0.001), and dedifferentiation (5.9% vs 1.5%, P < 0.001), but fewer grade 1 tumors compared with the pMMR group (31.8% vs 40.8%, P < 0.001). Median progression-free survival and overall survival have not been reached. After a median follow-up of 31 months (1-99 months), there was no difference in progression or recurrence rates between pMMR and dMMR tumors (19.5% vs 16.5%; P = 0.31). However, among those with nonendometrioid tumors, recurrence and mortality rates were significantly higher for pMMR than dMMR tumors (42.0% vs 10.0%, P = 0.001, and 36.1% vs 13.1%, P = 0.01, respectively), despite similar stage and lymphovascular space invasion distributions. DISCUSSION: In this population-based study, there were no significant differences in recurrence or survival outcomes according to MMR status in endometrial cancer. However, among those with nonendometrioid tumors, there were lower recurrence and mortality rates associated with MMR-deficient compared with MMR-proficient tumors.