Citations

Abstract Background: Chronic inflammation is implicated in ovarian carcinogenesis, but how different inflammation-related exposures individually or jointly affect histotype-specific associations remains unclear. Materials and Methods: We pooled data from 16 case-control studies in the Ovarian Cancer Association Consortium to evaluate associations of eight inflammation-related factors (anti-inflammatory: aspirin use, tubal ligation (TL); pro-inflammatory: endometriosis, obesity, lifetime ovulatory cycles (LOC), smoking, pelvic inflammatory disease (PID), polycystic ovary syndrome (PCOS)) with epithelial ovarian cancer (OvC) by histologic subtype. We examined individual associations and clustering of risk factors across histotypes and computed population attributable risk (PAR) for each factor. We assessed additive and multiplicative interactions for exposure combinations. Results: Associations with OvC risk differed by histotype (e.g., high-grade serous: aspirin: OR=0.90; 95%CI 0.82, 0.99; TL: OR=0.80; 95%CI 0.73, 0.88; overall serous: endometriosis: OR=1.17; 95%CI 1.03, 1.31; high LOC: OR=1.42; 95%CI 1.28, 1.58; obesity (low-grade serous): OR=1.50; 95%CI 1.14, 1.98). Clustering analyses showed highly correlated risk profiles in endometrioid and clear cell (r=0.91). High-grade serous and mucinous profiles were moderately correlated with endometrioid and clear cell (r=0.60) tumors. The profile for low-grade serous (r=0.36) tumors was distinct from other histotypes. PAR estimates suggested modifying aspirin use, TL, and LOCs could substantially reduce burdens of endometrioid, clear cell and mucinous tumors. Out of 28 exposure combinations tested in overall OvC and 189 by histotype, we observed 12 interactions. Not using aspirin regularly showed positive additive interactions with obesity and high LOCs, particularly in endometrioid tumors (obesity relative excess risk due to interaction (RERI)=0.74, 95%CI 0.31, 1.18; Pint=0.001 for; LOCs RERI=0.80, 95%CI 0.03, 1.56; Pint=0.04). Not using aspirin regularly also showed a positive additive interaction with endometriosis in clear cell tumors (RERI=1.77, 95%CI 0.03, 3.52; Pint=0.05). Lack of TL showed positive interactions with obesity in endometrioid (RERI=0.86, 95%CI 0.17, 1.53; Pint=0.01) and mucinous (RERI=1.10, 95%CI 0.23, 1.97; Pint=0.01) tumors, while negative additive interactions were observed for smoking and endometriosis in endometrioid tumors (RERI=-1.12, 95%CI -2.19, -0.05; Pint=0.04). A multiplicative interaction was observed between obesity and endometriosis in mucinous tumors (Pint=0.01). Conclusion: The findings suggest ovarian tumorigenesis is strongly shaped by pro- and anti-inflammatory pathways that act largely independently. Further examining these pathways may clarify the origins of histotype heterogeneity and guide prevention strategies. Citation Format: Maxwell Akonde, Britton Trabert, SHELLEY TWOROGER, Allan Jensen, Kathryn L. Terry, Joshua Sampson, Hoda Anton-Culver, David Bowtell, Elisa V. Bandera, Angela Brooks-Wilson, Andrew Berchuck, Daniel William Cramer, Linda S. Cook, Julie M. Cunningham, Jennifer A. Doherty, Ellen L. Goode, Marc T. Goodman, Holly Ruth Harris, Susanne K. Kjaer, Nhu Le, Alice Wen-Ron Lee, Francesmary Modugno, Kirsten B. Moysich, Celeste Pearce, Malcolm C. Pike, Harvey A. Risch, Mary A. Rossing, Joellen M. Schildkrau, Daniel O. Stram, Rebecca Sutphen, David Van Den Berg, Penelope M. Webb, Anna Wu, Argyrios Ziogas, Nicolas A. Wentzensen. Inflammation-related exposures and histotype- specific ovarian cancer risk in the Ovarian Cancer Association Consortium (OCAC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 6261.

Abstract Background: Ovarian high-grade serous carcinomas (HGSC) comprise four distinct molecular subtypes based on mRNA expression patterns, with differential survival. Understanding risk factor associations is important to elucidate the etiology of HGSC. We investigated associations between different epidemiologic risk factors and HGSC molecular subtypes. Methods: We pooled data from 11 case–control studies with epidemiologic and tumor gene expression data from custom NanoString CodeSets developed through a collaboration within the Ovarian Tumor Tissue Analysis consortium. The PrOTYPE-validated NanoString-based 55-gene classifier was used to assign HGSC gene expression subtypes. We examined associations between epidemiologic factors and HGSC subtypes in 2,070 cases and 16,633 controls using multivariable-adjusted polytomous regression models. Results: Among the 2,070 HGSC cases, 556 (27%) were classified as C1.MES, 340 (16%) as C5.PRO, 538 (26%) as C2.IMM, and 636 (31%) as C4.DIF. The key factors, including oral contraceptive use, parity, breastfeeding, and family history of ovarian cancer, were similarly associated with all subtypes. Heterogeneity was observed for several factors. Former smoking [OR = 1.25; 95% confidence interval (CI) = 1.03, 1.51] and genital powder use (OR = 1.42; 95% CI = 1.08, 1.86) were uniquely associated with C2.IMM. History of endometriosis was associated with C5.PRO (OR = 1.46; 95% CI = 0.98, 2.16) and C4.DIF (OR = 1.27; 95% CI = 0.94, 1.71) only. Family history of breast cancer (OR = 1.44; 95% CI = 1.16, 1.78) and current smoking (OR = 1.40; 95% CI = 1.11, 1.76) were associated with C4.DIF only. Conclusions: This study observed heterogeneous associations of epidemiologic and modifiable factors with HGSC molecular subtypes. Impact: The different patterns of associations may provide key information about the etiology of the four subtypes.

This cross-sectional study evaluates the prevalence of and characteristics associated with discontinuation of cancer treatment among patients who received a diagnosis of COVID-19 during their treatment planning.

ImportanceRacially and ethnically minoritized US adults were disproportionately impacted by the COVID-19 pandemic and experience poorer cancer outcomes, including inequities in cancer treatment delivery.ObjectiveTo evaluate racial and ethnic disparities in cancer treatment delays and discontinuations (TDDs) among patients with cancer and SARS-CoV-2 during different waves of the COVID-19 pandemic in the United States.Design, Setting, and ParticipantsThis cross-sectional study used data from the American Society of Clinical Oncology Survey on COVID-19 in Oncology Registry (data collected from April 2020 to September 2022), including patients with cancer also diagnosed with SARS-CoV-2 during their care at 69 US practices. Racial and ethnic differences were examined during 5 different waves of the COVID-19 pandemic in the United States based on case surge (before July 2020, July to November 2020, December 2020 to March 2021, April 2021 to February 2022, and March to September 2022).ExposuresRace and ethnicity.Main Outcomes and MeasuresTDD was defined as any cancer treatment postponed more than 2 weeks or cancelled with no plans to reschedule. To evaluate TDD associations with race and ethnicity, adjusted prevalence ratios (aPRs) were estimated using multivariable Poisson regression, accounting for nonindependence of patients within clinics, adjusting for age, sex, body mass index, comorbidities, cancer type, cancer extent, and SARS-CoV-2 severity (severe defined as death, hospitalization, intensive care unit admission, or mechanical ventilation).ResultsA total of 4054 patients with cancer and SARS-CoV-2 were included (143 [3.5%] American Indian or Alaska Native, 176 [4.3%] Asian, 517 [12.8%] Black or African American, 469 [11.6%] Hispanic or Latinx, and 2747 [67.8%] White; 2403 [59.3%] female; 1419 [35.1%] aged 50-64 years; 1928 [47.7%] aged ≥65 years). The analysis focused on patients scheduled (at SARS-CoV-2 diagnosis) to receive drug-based therapy (3682 [90.8%]), radiation therapy (382 [9.4%]), surgery (218 [5.4%]), or transplant (30 [0.7%]), of whom 1853 (45.7%) experienced TDD. Throughout the pandemic, differences in racial and ethnic inequities based on case surge with overall TDD decreased over time. In multivariable analyses, non-Hispanic Black (third wave: aPR, 1.56; 95% CI, 1.31-1.85) and Hispanic or Latinx (third wave: aPR, 1.35; 95% CI, 1.13-1.62) patients with cancer were more likely to experience TDD compared with non-Hispanic White patients during the first year of the pandemic. By 2022, non-Hispanic Asian patients (aPR, 1.51; 95% CI, 1.08-2.12) were more likely to experience TDD compared with non-Hispanic White patients, and non-Hispanic American Indian or Alaska Native patients were less likely (aPR, 0.37; 95% CI, 0.16-0.89).Conclusions and RelevanceIn this cross-sectional study of patients with cancer and SARS-CoV-2, racial and ethnic inequities existed in TDD throughout the pandemic; however, the disproportionate burden among racially and ethnically minoritized patients with cancer varied across SARS-CoV-2 waves. These inequities may lead to downstream adverse impacts on cancer mortality among minoritized adults in the United States.

Abstract Background: With the widespread use of multigene panel genetic testing, population-based studies are necessary to accurately assess penetrance in unselected individuals. We evaluated the prevalence of germline pathogenic or likely pathogenic variants (mutations) in 12 cancer-predisposition genes and associations with ovarian cancer risk in three population-based prospective studies [Nurses’ Health Study (NHS), NHSII, Cancer Prevention Study II]. Methods: We included women with epithelial ovarian or peritoneal cancer (n = 776) and controls who were alive and had at least one intact ovary at the time of the matched case diagnosis (n = 1,509). Germline DNA was sequenced for mutations in 12 genes. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for ovarian cancer risk by mutation status. Results: The mutation frequency across all 12 genes was 11.2% in cases and 3.3% in controls (P < 0.0001). BRCA1 and BRCA2 were the most frequently mutated (3.5% and 3.8% of cases and 0.3% and 0.5% of controls, respectively) and were associated with increased ovarian cancer risk [OR, BRCA1 = 12.38; 95% confidence interval (CI) = 4.72–32.45; OR, BRCA2 = 9.18; 95% CI = 3.98–21.15]. Mutation frequencies for the other genes were ≤1.0% and only PALB2 was significantly associated with risk (OR = 5.79; 95% CI = 1.09–30.83). There was no difference in survival for women with a BRCA germline mutation versus no mutation. Conclusions: Further research is needed to better understand the role of other mutations in ovarian cancer among unselected populations. Impact: Our data support guidelines for germline genetic testing for BRCA1 and BRCA2 among women diagnosed with epithelial ovarian cancer; testing for PALB2 may be warranted.

AbstractBackgroundKnown risk alleles for epithelial ovarian cancer (EOC) account for approximately 40% of the heritability for EOC. Copy number variants (CNVs) have not been investigated as EOC risk alleles in a large population cohort.MethodsSingle nucleotide polymorphism array data from 13 071 EOC cases and 17 306 controls of White European ancestry were used to identify CNVs associated with EOC risk using a rare admixture maximum likelihood test for gene burden and a by-probe ratio test. We performed enrichment analysis of CNVs at known EOC risk loci and functional biofeatures in ovarian cancer–related cell types.ResultsWe identified statistically significant risk associations with CNVs at known EOC risk genes; BRCA1 (PEOC = 1.60E-21; OREOC = 8.24), RAD51C (Phigh-grade serous ovarian cancer [HGSOC] = 5.5E-4; odds ratio [OR]HGSOC = 5.74 del), and BRCA2 (PHGSOC = 7.0E-4; ORHGSOC = 3.31 deletion). Four suggestive associations (P < .001) were identified for rare CNVs. Risk-associated CNVs were enriched (P < .05) at known EOC risk loci identified by genome-wide association study. Noncoding CNVs were enriched in active promoters and insulators in EOC-related cell types.ConclusionsCNVs in BRCA1 have been previously reported in smaller studies, but their observed frequency in this large population-based cohort, along with the CNVs observed at BRCA2 and RAD51C gene loci in EOC cases, suggests that these CNVs are potentially pathogenic and may contribute to the spectrum of disease-causing mutations in these genes. CNVs are likely to occur in a wider set of susceptibility regions, with potential implications for clinical genetic testing and disease prevention.

Abstract Introduction: There is growing evidence to support a modest inverse association between daily aspirin use and ovarian cancer risk. We previously hypothesized that this association may differ by immune cell infiltration. In our prior study evaluating heterogeneity by tumor-associated macrophage (TAM) infiltration, aspirin use was associated with lower risk of ovarian cancer with high protumorigenic M2-type TAM infiltration, but not low M2-type TAM infiltration. The goal of the present study was to evaluate the hypothesis that the association between aspirin use and ovarian cancer risk also differs by infiltration with tumor-infiltrating lymphocytes (TILs). Methods: We included cases and matched controls from the Nurses’ Health Study (NHS), NHSII, and New England Case Control Study. Study participants self-reported aspirin use including regular use (≥1 x per week), duration of use, and number of tablets. A gynecologic pathologist (JLH), who was blinded to exposure status, reviewed hematoxylin and eosin stained tumor slides to quantify TILs for all cases (n=547). We used polytomous logistic regression, adjusted for ovarian cancer risk factors, to estimate odds ratios (OR) for aspirin use and ovarian cancer risk by TIL infiltration. Results: Overall, recent aspirin use was associated with lower risk of ovarian cancer compared with no regular aspirin use (OR=0.65, 95%CI=0.47-0.89). Recent aspirin use was associated with a lower risk of ovarian cancer exhibiting TIL infiltration (OR=0.38, 95%CI=0.26-0.56) but not with TIL-negative cancers (OR=1.00, 95%CI=0.71-1.41; p-heterogeneity <0.001). We observed similar results for aspirin duration and tablets. For duration, comparing ≥10 years of aspirin use to <1 year we observed a significantly lower risk of ovarian cancer with TILs (OR=0.47, 95%CI=0.41-0.71; p-trend=0.004), but a nonsignificant reduction for ovarian cancer without TILs (OR=0.86, 95%CI=0.59-1.26; p-trend=0.72; p-heterogeneity=0.03). Comparing ≥6 tablets to <1 tablet per week, there was evidence of a lower risk of ovarian cancer with TILs (OR=0.47, 95%CI=0.30-0.75; p-trend=0.001) but not without TILs (OR=1.02, 95%CI=0.70-1.48; p-trend=0.84; p-heterogeneity=0.003). Conclusions: Our results suggest that prediagnosis aspirin use may be an important modulator of immune cell infiltration in ovarian tumors, supporting an immunogenic mechanism for aspirin in ovarian carcinogenesis. Further work is under way to evaluate nonaspirin nonsteroidal anti-inflammatory drugs, and to consider which subsets of TAMs and TILs may be driving heterogeneity in the associations between anti-inflammatory drugs and ovarian cancer risk. Citation Format: Mollie E. Barnard, Britton Trabert, Jonathan L. Hecht, Ellen L. Goode, Naoko Sasamoto, Kathryn L. Terry, Shelley S. Tworoger. Aspirin use and ovarian cancer risk by lymphocyte infiltration [abstract]. In: Proceedings of the AACR Special Conference on Modernizing Population Sciences in the Digital Age; 2019 Feb 19-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(9 Suppl):Abstract nr A19.

AbstractAn association between genetic variants in the vitamin D receptor (VDR) gene and epithelial ovarian cancer (EOC) was previously reported in women of African ancestry (AA). We sought to examine associations between genetic variants in VDR and additional genes from vitamin D biosynthesis and pathway targets (EGFR, UGT1A, UGT2A1/2, UGT2B, CYP3A4/5, CYP2R1, CYP27B1, CYP24A1, CYP11A1, and GC). Genotyping was performed using the custom‐designed 533,631 SNP Illumina OncoArray with imputation to the 1,000 Genomes Phase 3 v5 reference set in 755 EOC cases, including 537 high‐grade serous (HGSOC), and 1,235 controls. All subjects are of African ancestry (AA). Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (CI). We further evaluated statistical significance of selected SNPs using the Bayesian False Discovery Probability (BFDP). A significant association with EOC was identified in the UGT2A1/2 region for the SNP rs10017134 (per allele OR = 1.4, 95% CI = 1.2‐1.7, P = 1.2 × 10−6, BFDP = 0.02); and an association with HGSOC was identified in the EGFR region for the SNP rs114972508 (per allele OR = 2.3, 95% CI = 1.6‐3.4, P = 1.6 × 10−5, BFDP = 0.29) and in the UGT2A1/2 region again for rs1017134 (per allele OR = 1.4, 95% CI = 1.2‐1.7, P = 2.3 × 10−5, BFDP = 0.23). Genetic variants in the EGFR and UGT2A1/2 may increase susceptibility of EOC in AA women. Future studies to validate these findings are warranted. Alterations in EGFR and UGT2A1/2 could perturb enzyme efficacy, proliferation in ovaries, impact and mark susceptibility to EOC.

Abstract DNA methylation is instrumental for gene regulation. Global changes in the epigenetic landscape have been recognized as a hallmark of cancer. However, the role of DNA methylation in epithelial ovarian cancer (EOC) remains unclear. In this study, high-density genetic and DNA methylation data in white blood cells from the Framingham Heart Study (N = 1,595) were used to build genetic models to predict DNA methylation levels. These prediction models were then applied to the summary statistics of a genome-wide association study (GWAS) of ovarian cancer including 22,406 EOC cases and 40,941 controls to investigate genetically predicted DNA methylation levels in association with EOC risk. Among 62,938 CpG sites investigated, genetically predicted methylation levels at 89 CpG were significantly associated with EOC risk at a Bonferroni-corrected threshold of P < 7.94 × 10−7. Of them, 87 were located at GWAS-identified EOC susceptibility regions and two resided in a genomic region not previously reported to be associated with EOC risk. Integrative analyses of genetic, methylation, and gene expression data identified consistent directions of associations across 12 CpG, five genes, and EOC risk, suggesting that methylation at these 12 CpG may influence EOC risk by regulating expression of these five genes, namely MAPT, HOXB3, ABHD8, ARHGAP27, and SKAP1. We identified novel DNA methylation markers associated with EOC risk and propose that methylation at multiple CpG may affect EOC risk via regulation of gene expression. Significance: Identification of novel DNA methylation markers associated with EOC risk suggests that methylation at multiple CpG may affect EOC risk through regulation of gene expression.

As a follow‐up to genome‐wide association analysis of common variants associated with ovarian carcinoma (cancer), our study considers seven well‐known ovarian cancer risk factors and their interactions with 28 genome‐wide significant common genetic variants. The interaction analyses were based on data from 9971 ovarian cancer cases and 15,566 controls from 17 case–control studies. Likelihood ratio and Wald tests for multiplicative interaction and for relative excess risk due to additive interaction were used. The top multiplicative interaction was noted between oral contraceptive pill (OCP) use (ever vs. never) and rs13255292 (p value = 3.48 × 10−4). Among women with the TT genotype for this variant, the odds ratio for OCP use was 0.53 (95% CI = 0.46–0.60) compared to 0.71 (95%CI = 0.66–0.77) for women with the CC genotype. When stratified by duration of OCP use, women with 1–5 years of OCP use exhibited differential protective benefit across genotypes. However, no interaction on either the multiplicative or additive scale was found to be statistically significant after multiple testing correction. The results suggest that OCP use may offer increased benefit for women who are carriers of the T allele in rs13255292. On the other hand, for women carrying the C allele in this variant, longer (5+ years) use of OCP may reduce the impact of carrying the risk allele of this SNP. Replication of this finding is needed. The study presents a comprehensive analytic framework for conducting gene–environment analysis in ovarian cancer.