McAlpine, Jessica N.

Abstract Background Opportunistic bilateral salpingectomy (OBS), the removal of fallopian tubes during hysterectomy or instead of tubal ligation, is recommended to reduce ovarian cancer risk. However, data on the effectiveness of prophylactic OBS is limited. Methods This population-based retrospective cohort included individuals aged 18–80 in Ontario, Canada, who underwent OBS or comparator surgeries (hysterectomy with ovarian and tubal conservation or tubal ligation) from 2011 to 2023. Individuals with gynecologic cancer before or within six months of surgery were excluded. Hazard ratios and 95% confidence intervals were estimated using Cox proportional hazards regression. Sensitivity analyses varied the time between surgery and cancer diagnosis to account for pre-existing serous tubal intraepithelial carcinomas. Results Among 196,839 individuals, 57,941 underwent OBS and 138,898 underwent comparator surgeries. 142 epithelial ovarian cancers were diagnosed (19 in the OBS group and 123 in the comparator surgery group). OBS was associated with reduced risk of any ovarian carcinoma, with an adjusted hazard ratio (aHR) of 0.60 (95% CI, 0.36 to 0.98). For serous ovarian carcinoma (high- and low-grade combined due to missing grade data), the aHR was 0.47 (95% CI, 0.22 to 0.99). Sensitivity analyses with 12- and 18-month intervals showed aHRs of 0.59 (95% CI, 0.35 to 0.99) and 0.60 (95% CI, 0.35 to 1.01) for all ovarian carcinomas, and 0.49 (95% CI, 0.23 to 1.01) and 0.47 (95% CI, 0.22 to 0.99) for serous ovarian carcinoma, respectively. Conclusions OBS was associated with reduced risk of ovarian carcinoma, supporting its role as a primary prevention strategy.

This cohort study evaluates the reduction in risk of high-grade serous carcinoma among women undergoing opportunistic bilateral salpingectomy in Canada.

Abstract Introduction: The purpose of this study is to evaluate the effectiveness of opportunistic salpingectomy (OS), a procedure that aims to remove only the fallopian tubes of general population risk women, for the prevention of epithelial ovarian cancer. Currently, the method of prevention for individuals at high risk of ovarian cancer involves a bilateral salpingo-oophorectomy (BSO), a procedure that removes both the fallopian tubes and ovaries. However, this procedure is not recommended for individuals of the general population, who make up about 80% of ovarian cancers, due to negative health implications to the cardiovascular and skeletal systems because of surgically induced menopause. The effectiveness of the OS in preventing ovarian cancers and how the procedure impacts the histotype distribution of ovarian cancers remains unknown. Study Methods: This study uses a population-based approach and a case-based approach to determine the effectiveness of OS and its impact on histotype distribution, respectively. For the population-based analysis, we will search through clinical databases to acquire cases of individuals who have had an OS and a tumor. A control population who have their fallopian tubes in-tact will also be acquired. A cox-proportional hazard analysis will be performed to determine the effectiveness of the procedure. Using pathological records, the case-based ascertainment of tumors from individuals who have had an OS will be selected and reviewed for histotype confirmation. Fallopian tubes of these patients will also be reviewed for precursor lesions. This cohort will be compared to a historical histotype distribution of ovarian cancers. Results: For the population-based approach, we have to date, identified less than five serous ovarian cancers in individuals who have had an OS (n=40, 477). A comparator surgery was used as a control and showed 21 cancers. For the case-based approach, we have partnered with 23 collaborating institutions from around the world to identify tumors in individuals who have had an OS. We have identified 26 epithelial ovarian cancers, with the most lethal gynecological histotype, high grade serous carcinoma (HGSC), accounting for 23.1% of the total proportion of epithelial ovarian cancer cases (n=6/26). This is significantly less than the historical histotype distribution of HGSC, which is 69.3% (Fisher’s exact test, p<0.0001). One HGSC case had a precursor lesion called a serous tubal intraepithelial carcinoma (STIC) while reviewing fallopian tubes of this individual. TP53 mutation analysis on one HGSC tumor sample showed a frameshift mutation in TP53 (c229fs) with the tumor and the corresponding STIC staining negative for p53 protein expression by immunohistochemistry. Conclusion: This evidence demonstrates the effectiveness of opportunistic salpingectomy for the prevention of ovarian cancer and shows a histotype distribution shift, with the most lethal gynecological malignancy having a significant reduction in cases following the procedure. Citation Format: Ramlogan Sowamber, Alice J. Mei, Paramdeep Kaur, Julianne McLeod, Emily McKay, Alex Lukey, Jamie Bakkum-Gamez, Natalia Buza, Paul Cohen, Kyle Devins, Rhonda Farrell, Christine Garcia, Blake Gilks, Ellen Goode, Anjelica Hodgson, Brooke Howitt, Pei Hui, Jutta Huvila, Anthony Karnezis, Kianoosh Keyhanian, Mary Kinloch, Martin Köbel, Felix KF. Kommoss, Lawrence Kushi, Janice S. Kwon, Kara Long-Roche, Anais Malpica, Jessica N. McAlpine, Dianne Miller, Esther Oliva, Andrea Palicelli, Aleksandra Paliga, Carlos Parra-Herran, Celeste Leigh Pearce, Sharnel Perera, Jurgen M. Piek, Haiyan Qiu, Joseph Rabban, Robert Rome, Miranda Steenbeek, Rebecca Stone, Aline Talhouk, Kristin M. Tischer, Britton Trabert, Penelope M. Webb, John R. Zalcberg, Gillian E. Hanley, David G. Huntsman. Evaluating the effectiveness of opportunistic salpingectomy (OS) for the prevention of epithelial ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Ovarian Cancer Research; 2025 Sep 19-21; Denver, CO. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl):Abstract nr B045.

Abstract Purpose: Endometrioid ovarian carcinoma (ENOC) is the second most-common type of ovarian carcinoma, comprising 10%–20% of cases. Recently, the study of ENOC has benefitted from comparisons to endometrial carcinomas including defining ENOC with four prognostic molecular subtypes. Each subtype suggests differential mechanisms of progression, although tumor-initiating events remain elusive. There is evidence that the ovarian microenvironment may be critical to early lesion establishment and progression. However, while immune infiltrates have been well studied in high-grade serous ovarian carcinoma, studies in ENOC are limited. Experimental Design: We report on 210 ENOC, with clinical follow-up and molecular subtype annotation. Using multiplex IHC and immunofluorescence, we examine the prevalence of T-cell lineage, B-cell lineage, macrophages, and populations with programmed cell death protein 1 or programmed death-ligand 1 across subtypes of ENOC. Results: Immune cell infiltrates in tumor epithelium and stroma showed higher densities in ENOC subtypes with known high mutation burden (POLEmut and MMRd). While molecular subtypes were prognostically significant, immune infiltrates were not (overall survival P > 0.2). Analysis by molecular subtype revealed that immune cell density was prognostically significant in only the no specific molecular profile (NSMP) subtype, where immune infiltrates lacking B cells (TILB minus) had inferior outcome (disease-specific survival: HR, 4.0; 95% confidence interval, 1.1–14.7; P < 0.05). Similar to endometrial carcinomas, molecular subtype stratification was generally superior to immune response in predicting outcomes. Conclusions: Subtype stratification is critical for better understanding of ENOC, in particular the distribution and prognostic significance of immune cell infiltrates. The role of B cells in the immune response within NSMP tumors warrants further study.

Abstract Background: Accumulating evidence suggests a relationship between endometrial cancer and ovarian cancer. Independent genome-wide association studies (GWAS) for endometrial cancer and ovarian cancer have identified 16 and 27 risk regions, respectively, four of which overlap between the two cancers. We aimed to identify joint endometrial and ovarian cancer risk loci by performing a meta-analysis of GWAS summary statistics from these two cancers. Methods: Using LDScore regression, we explored the genetic correlation between endometrial cancer and ovarian cancer. To identify loci associated with the risk of both cancers, we implemented a pipeline of statistical genetic analyses (i.e., inverse-variance meta-analysis, colocalization, and M-values) and performed analyses stratified by subtype. Candidate target genes were then prioritized using functional genomic data. Results: Genetic correlation analysis revealed significant genetic correlation between the two cancers (rG = 0.43, P = 2.66 × 10−5). We found seven loci associated with risk for both cancers (PBonferroni < 2.4 × 10−9). In addition, four novel subgenome-wide regions at 7p22.2, 7q22.1, 9p12, and 11q13.3 were identified (P < 5 × 10−7). Promoter-associated HiChIP chromatin loops from immortalized endometrium and ovarian cell lines and expression quantitative trait loci data highlighted candidate target genes for further investigation. Conclusions: Using cross-cancer GWAS meta-analysis, we have identified several joint endometrial and ovarian cancer risk loci and candidate target genes for future functional analysis. Impact: Our research highlights the shared genetic relationship between endometrial cancer and ovarian cancer. Further studies in larger sample sets are required to confirm our findings.

AbstractBackgroundBRCA1 methylation has been associated with homologous recombination deficiency, a biomarker of platinum sensitivity. Studies evaluating BRCA1-methylated tubal and ovarian cancer (OC) do not consistently support improved survival following platinum chemotherapy. We examine the characteristics of BRCA1-methylated OC in a meta-analysis of individual participant data.MethodsData of 2636 participants across 15 studies were analyzed. BRCA1-methylated tumors were defined according to their original study. Associations between BRCA1 methylation and clinicopathological characteristics were evaluated. The effects of methylation on overall survival (OS) and progression-free survival (PFS) were examined using mixed-effects models. All statistical tests were 2-sided.Results430 (16.3%) tumors were BRCA1-methylated. BRCA1 methylation was associated with younger age and advanced-stage, high-grade serous OC. There were no survival differences between BRCA1-methylated and non–BRCA1-methylated OC (median PFS = 20.0 vs 18.5 months, hazard ratio [HR] = 1.01, 95% CI = 0.87 to 1.16; P = .98; median OS = 46.6 vs 48.0 months, HR = 1.02, 95% CI = 0.87 to 1.18; P = .96). Where BRCA1/2 mutations were evaluated (n = 1248), BRCA1 methylation displayed no survival advantage over BRCA1/2-intact (BRCA1/2 wild-type non–BRCA1-methylated) OC. Studies used different methods to define BRCA1 methylation. Where BRCA1 methylation was determined using methylation-specific polymerase chain reaction and gel electrophoresis (n = 834), it was associated with improved survival (PFS: HR = 0.80, 95% CI = 0.66 to 0.97; P = .02; OS: HR = 0.80, 95% CI = 0.63 to 1.00; P = .05) on mixed-effects modeling.ConclusionBRCA1-methylated OC displays similar clinicopathological features to BRCA1-mutated OC but is not associated with survival. Heterogeneity within BRCA1 methylation assays influences associations. Refining these assays may better identify cases with silenced BRCA1 function and improved patient outcomes.

Abstract Background: Mucinous ovarian carcinomas (MC) and mucinous borderline ovarian tumours (MBOT) are associated with ERBB2 amplification and KRAS activating mutations. These events occur in a near-mutually exclusive pattern, and KRAS mutations are more prevalent in MBOTs than MC's whereas ERBB2 amplification is more frequently seen in MCs. Frequencies of mutations in other oncogenes and tumour suppressor genes in MC are not well established though TP53, BRAF, NRAS, and CDKN2A mutations have all been reported. As these carcinomas are commonly chemo-resistant a definitive molecular categorization of this subtype is needed as treatment options are explored. Methods: We undertook review of pathology reports and after exclusion of potential gastric, appendiceal or pancreatic involvement over 100 mucinous ovarian tumours were identified. HPV testing was undertaken to exclude rare metastasis from endocervical primary site. All specimens were assayed for p53 expression via TMA and subject to sequencing of common cancer gene hotspots using Ion-Torrent or Illumina MiSeq. Previously derived data on ERBB2 status was combined in our analysis and, where available, samples showing heterogeneity of ERBB2 amplification and any other Ras-pathway activating mutation were microdissected with components evaluated independently for concurrent hotspot mutations. Results: All samples were consistent with mucinous tumours of ovarian origin and none were HPV positive. We detected mutations in KRAS, BRAF, CDKN2A, TP53, PTEN, PIK3CA as well as presumed somatic/detrimental, variants in APC that have not previously been reported in mucinous tumours. Despite some samples having enriched tumour content, lower than expected allelic frequencies of KRAS activating mutations suggested intra-tumoural heterogeneity. This was consistent with results observed previously with rare ERBB2 amplification coinciding KRAS mutations. Conclusions: The prevalence of Ras-pathway mutations, especially amongst borderline lesions, suggests these mutations are critical for tumour onset. However varying allelic frequencies of KRAS mutations suggest progression to carcinoma is strongly influenced by other molecular features. Citation Format: Michael S. Anglesio, Robertson Mackenzie, Stefan Kommoss, Boris J. Winterhoff, Benjamin Kipp, Jaoquin Garcia, Jesse S. Voss, Kevin Halling, Sarah Kerr, Janine Senz, Winnie Yang, Magnus von Knebel Doeberitz, Elena-Sophie Prigge, Miriam Reuschenbach, Anna V. Tinker, Blake Gilks, Jamie N. Bakkum-Gamez, David G. Huntsman, Jessica N. McAlpine. Defining ovarian mucinous tumors: Cancer genes and heterogeneity. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A18.

AbstractMucinous ovarian carcinomas (MCs) typically do not respond to current conventional therapy. We have previously demonstrated amplification of HER2 in 6 of 33 (18.2%) mucinous ovarian carcinomas (MCs) and presented anecdotal evidence of response with HER2‐targeted treatment in a small series of women with recurrent HER2‐amplified (HER2+) MC. Here, we explore HER2 amplification and KRAS mutation status in an independent cohort of 189 MCs and 199 mucinous borderline ovarian tumours (MBOTs) and their association to clinicopathological features. HER2 status was assessed by immunohistochemistry (IHC), FISH, and CISH, and interpreted per ASCO/CAP guidelines, with intratumoural heterogeneity assessment on full sections, where available. KRAS mutation testing was performed with Sanger sequencing. Stage and grade were associated with recurrence on both univariate and multivariate analysis (p < 0.001). Assessment of HER2 status revealed overexpression/amplification of HER2 in 29/154 (18.8%) MCs and 11/176 (6.2%) MBOTs. There was excellent agreement between IHC, FISH, and CISH assessment of HER2 status (perfect concordance of HER2 0 or 1+ IHC with non‐amplified status, and 3+ IHC with amplified status). KRAS mutations were seen in 31/71 (43.6%) MCs and 26/33 (78.8%) MBOTs, and were near mutually exclusive of HER2 amplification. In the 189 MC cases, a total of 54 recurrences and 59 deaths (53 of progressive disease) were observed. Within MCs, either HER2 amplification/overexpression or KRAS mutation was associated with decreased likelihood of disease recurrence (p = 0.019) or death (p = 0.0041) when compared to cases with neither feature. Intratumoural heterogeneity was noted in 26% of HER2‐overexpressing cases. These data support the stratification of MCs for the testing of new treatments, with HER2‐targeted therapy as a viable option for HER2+ advanced or recurrent disease. Further research is required to delineate the molecular and clinical features of the ∼34% of MC cases with neither HER2 amplification nor KRAS mutations.