Plasma microRNA expression in adolescents and young adults with endometriosis: the importance of hormone use

Introduction

Prior studies have investigated the diagnostic potential of microRNA (miRNA) expression profiles for endometriosis. However, the vast majority of previous studies have only included adult women. Therefore, we sought to investigate differential expression of miRNAs among adolescents and young adults with endometriosis.

Methods

The Women's Health Study: from Adolescence to Adulthood (A2A) is an ongoing WERF EPHect compliant longitudinal cohort. Our analysis included 64 patients with surgically-confirmed endometriosis (96% rASRM stage I/II) and 118 females never diagnosed with endometriosis frequency matched on age (median = 21 years) and hormone use at blood draw. MicroRNA measurement was separated into discovery (10 cases and 10 controls) and internal replication (54 cases and 108 controls) phases. The levels of 754 plasma miRNAs were assayed in the discovery phase using PCR with rigorous internal control measures, with the relative expression of miRNA among cases vs. controls calculated using the 2-ΔΔCt method. miRNAs that were significant in univariate analyses stratified by hormone use were included in the internal replication phase. The internal replication phase was split 2:1 into a training and testing set and utilized FirePlex miRNA assay to assess 63 miRNAs in neural network analyses. The testing set of the validation phase was utilized to calculate the area under the curve (AUC) of the best fit models from the training set including hormone use as a covariate.

Results

In the discovery phase, 49 miRNAs were differentially expressed between endometriosis cases and controls. The associations of the 49 miRNAs differed by hormone use at the time of blood draw. Neural network analysis in the testing set of the internal replication phase determined a final model comprising 5 miRNAs (miR-542-3p, let-7b-3p, miR-548i, miR-769-5p, miR-30c-1-3p), yielding AUC = 0.77 (95% CI: 0.67-0.87, p < 0.001). Sensitivity in the testing dataset improved (83.3% vs. 72.2%) while the specificity decreased (58.3% vs. 72.2%) compared to the training set.

Conclusion

The results suggest that miR-542-3p, let-7b-3p, miR-548i, miR-769-5p, miR-30c-1-3p may be dysregulated among adolescent and young adults with endometriosis. Hormone use was a significant modifier of miRNA dysregulation and should be considered rigorously in miRNA diagnostic studies.

The Cancer Spectrum Theory

SUMMARY

Biological characteristics of tumors are heterogeneous, forming spectra in terms of several factors such as age at onset, anatomic spatial localization, tumor subtyping, and the degree of tumor aggressiveness (encompassing a neoplastic property spectrum). Instead of blindly using dichotomized approaches, the application of the multicategorical and continuous analysis approaches to detailed cancer spectrum data can contribute to a better understanding of the etiology of cancer, ultimately leading to effective prevention and precision oncology. We provide examples of cancer spectra and emphasize the importance of integrating the cancer spectrum theory into large-scale population cancer research.

Subgroups of pelvic pain are differentially associated with endometriosis and inflammatory comorbidities: a latent class analysis

ABSTRACT

Chronic pelvic pain is heterogeneous with potentially clinically informative subgroups. We aimed to identify subgroups of pelvic pain based on symptom patterns and investigate their associations with inflammatory and chronic pain-related comorbidities. Latent class analysis (LCA) identified subgroups of participants (n = 1255) from the Adolescence to Adulthood (A2A) cohort. Six participant characteristics were included in the LCA: severity, frequency, and impact on daily activities of both menstruation-associated (cyclic) and non-menstruation-associated (acyclic) pelvic pain. Three-step LCA quantified associations between LC subgroups, demographic and clinical variables, and 18 comorbidities (10 with prevalence ≥10%). Five subgroups were identified: none or minimal (23%), moderate cyclic only (28%), severe cyclic only (20%), moderate or severe acyclic plus moderate cyclic (9%), and severe acyclic plus severe cyclic (21%). Endometriosis prevalence within these 5 LCA-pelvic pain-defined subgroups ranged in size from 4% in "none or minimal pelvic pain" to 24%, 72%, 70%, and 94%, respectively, in the 4 pain subgroups, with statistically significant odds of membership only for the latter 3 subgroups. Migraines were associated with significant odds of membership in all 4 pelvic pain subgroups relative to those with no pelvic pain (adjusted odds ratios = 2.92-7.78), whereas back, joint, or leg pain each had significantly greater odds of membership in the latter 3 subgroups. Asthma or allergies had three times the odds of membership in the most severe pain group. Subgroups with elevated levels of cyclic or acyclic pain are associated with greater frequency of chronic overlapping pain conditions, suggesting an important role for central inflammatory and immunological mechanisms.

Plasma proteins and persistent postsurgical pelvic pain among adolescents and young adults with endometriosis

BACKGROUND

Noninvasive biomarkers that predict surgical treatment response would inform personalized treatments and provide insight into potential biologic pathways underlying endometriosis-associated pain and symptom progression.

OBJECTIVE

To use plasma proteins in relation to the persistence of pelvic pain following laparoscopic surgery in predominantly adolescents and young adults with endometriosis using a multiplex aptamer-based proteomics biomarker discovery platform.

STUDY DESIGN

We conducted a prospective analysis including 142 participants with laparoscopically-confirmed endometriosis from the Women's Health Study: From Adolescence to Adulthood observational longitudinal cohort with study enrollment from 2012-2018. Biologic samples and patient data were collected with modified World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonization Project tools. In blood collected before laparoscopic ablation or excision of endometriosis, we simultaneously measured 1305 plasma protein levels, including markers for immunity, angiogenesis, and inflammation, using SomaScan. Worsening or persistent postsurgical pelvic pain was defined as having newly developed, persistent (ie, stable), or worsening severity, frequency, or persistent life interference of dysmenorrhea or acyclic pelvic pain at 1-year postsurgery compared with presurgery. We calculated odds ratios and 95% confidence intervals using logistic regression adjusted for age, body mass index, fasting status, and hormone use at blood draw. We applied Ingenuity Pathway Analysis and STRING analysis to identify pathophysiologic pathways and protein interactions.

RESULTS

The median age at blood draw was 17 years (interquartile range, 15-19 years), and most participants were White (90%). All had superficial peritoneal lesions only and were treated by excision or ablation. One-year postsurgery, pelvic pain worsened or persisted for 76 (54%) of these participants with endometriosis, whereas pelvic pain improved for 66 (46%). We identified 83 proteins associated with worsening or persistent pelvic pain 1-year postsurgery (nominal P<.05). Compared with those with improved pelvic pain 1-year postsurgery, those with worsening or persistent pelvic pain had higher plasma levels of CD63 antigen (odds ratio, 2.98 [95% confidence interval, 1.44-6.19]) and CD47 (odds ratio, 2.68 [95% confidence interval, 1.28-5.61]), but lower levels of Sonic Hedgehog protein (odds ratio, 0.55 [95% confidence interval, 0.36-0.84]) in presurgical blood. Pathways related to cell migration were up-regulated, and pathways related to angiogenesis were down-regulated in those with worsening or persistent postsurgical pelvic pain compared with those with improved pain. When we examined the change in protein levels from presurgery to postsurgery and its subsequent risk of worsening or persistent postsurgical pain at 1-year follow-up, we observed increasing levels of Sonic Hedgehog protein from presurgery to postsurgery was associated with a 4-fold increase in the risk of postsurgical pain (odds ratio [quartile 4 vs 1], 3.86 [1.04-14.33]).

CONCLUSION

Using an aptamer-based proteomics platform, we identified plasma proteins and pathways associated with worsening or persistent pelvic pain postsurgical treatment of endometriosis among adolescents and young adults that may aid in risk stratification of individuals with endometriosis.

Large-scale genome-wide association study of 398,238 women unveils seven novel loci associated with high-grade serous epithelial ovarian cancer risk

Background

Nineteen genomic regions have been associated with high-grade serous ovarian cancer (HGSOC). We used data from the Ovarian Cancer Association Consortium (OCAC), Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA), UK Biobank (UKBB), and FinnGen to identify novel HGSOC susceptibility loci and develop polygenic scores (PGS).

Methods

We analyzed >22 million variants for 398,238 women. Associations were assessed separately by consortium and meta-analysed. OCAC and CIMBA data were used to develop PGS which were trained on FinnGen data and validated in UKBB and BioBank Japan.

Results

Eight novel variants were associated with HGSOC risk. An interesting discovery biologically was finding that TP53 3'-UTR SNP rs78378222 was associated with HGSOC (per T allele relative risk (RR)=1.44, 95%CI:1.28-1.62, P=1.76×10-9). The optimal PGS included 64,518 variants and was associated with an odds ratio of 1.46 (95%CI:1.37-1.54) per standard deviation in the UKBB validation (AUROC curve=0.61, 95%CI:0.59-0.62).

Conclusions

This study represents the largest GWAS for HGSOC to date. The results highlight that improvements in imputation reference panels and increased sample sizes can identify HGSOC associated variants that previously went undetected, resulting in improved PGS. The use of updated PGS in cancer risk prediction algorithms will then improve personalized risk prediction for HGSOC.

Differences in characteristics and use of complementary and alternative methods for coping with endometriosis-associated acyclic pelvic pain across adolescence and adulthood

Introduction

Over four million women in the US alone have been diagnosed with endometriosis. For those living with this disease, surgery and hormonal treatment reduce associated pelvic pain in some, while others continue to experience life impacting pain. Therefore, identification of accessible and cost-effective methods of pain reduction to compliment current treatment is urgently needed. Our objective was to quantify the prevalence of complementary and alternative methods used to manage acyclic pelvic pain and their reported benefit among women of different age groups living with endometriosis.

Methods

We used baseline questionnaire data from laparoscopically-confirmed endometriosis cases who completed a WERF EPHect compliant questionnaire in the longitudinal cohort of The Women's Health Study: From Adolescence to Adulthood (A2A). Participants with acyclic pelvic pain were asked to indicate specific methods or activities that either helped or worsened their pelvic/lower abdominal pain. Differences among age groups [adolescent (<18 years), young adult (18-25 years), and adult (>25 years)] were assessed using Fisher's exact test.

Results

Of the 357 participants included in analysis, sleep for coping was reported more frequently among adolescents (n = 59, 57.3%) compared to young adults (n = 40, 44.0%) and adults (n = 19, 31.1%; p = 0.004). Adolescents also reported more frequent use of music (n = 29, 21.2%) than young adults (n = 10, 7.0%) and adults (n = 7, 9.1%; p = 0.001). Exercise worsened pain most commonly among adolescents (n = 82, 59.9%), followed by younger adults (n = 67, 46.9%), and adults (n = 27, 35.1%; p = 0.002).

Discussion

Our analysis of participants in the A2A cohort showed that the prevalence of complementary and alternative methods used for coping with endometriosis-associated acyclic pelvic pain varied by age group. Future studies should aim to provide information that will further inform decisions in making care plans for managing endometriosis-associated pain that is effective, accessible, and tailored to the preferences of the patient.

Visualized peritoneal fluid variation in adolescents and young adults with endometriosis: is there more to it?

Background

Peritoneal fluid is a medium for endometriosis-associated biomarker discovery from which the local peritoneal environment and pathophysiologic pathways are often inferred. Therefore, we evaluated the associations between peritoneal fluid color and volume at time of endometriosis-related laparoscopic surgery with patient characteristics, endometriosis type and lesion location in adolescents and young adults with endometriosis.

Methods

We conducted a cross-sectional analysis among 545 patients undergoing surgery for endometriosis who enrolled in the Women's Health Study: from Adolescence to Adulthood cohort study. Patient characteristics, surgically visualized endometriosis phenotypes, and gross characteristics of peritoneal fluid were collected in compliance with World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonization Project (EPHect) tools. Chi-square or Fisher's exact tests were applied to test for differences across categories.

Results

Most of the patients were adolescents or young adults (86% age <25 years) of white race (89%), with only superficial peritoneal lesions and rASRM stage = I/II observed at surgery (both 95%). We observed variation in peritoneal fluid color across different menstrual cycle phases at time of surgery (p = 0.006). Among those who were cycling at time of surgery, endometriosis patients with red peritoneal fluid were most likely to be in the proliferative phase (49%) compared to the secretory phase (27%), while those with yellow or orange peritoneal fluid were most likely to be in the secretory phase (57% and 86% respectively). Yellow color was significantly less common in those taking combined oral contraceptives but much more common with progesterone only formulation exposure (p = 0.002). Peritoneal fluid volume did not differ by cycle phase but was more likely to be low (≤6 ml) for those exposed to hormones at time of surgery (p = 0.01). Those with acyclic pelvic pain were less likely to have red peritoneal fluid (p = 0.001) but had greater volume (p = 0.02) compared to those without.

Conclusion

Our findings highlight the importance of accounting for menstrual cycle phase and hormonal exposures when designing research using peritoneal fluid samples and inferring from biomarker results intended to advance our understanding of endometriosis and associated symptom pathophysiology.

Early Detection of Ovarian Cancer

The risk of death from ovarian cancer is highly associated with the clinical stage at diagnosis. Efforts to implement screening for ovarian cancer have been largely unsuccessful, due to the low prevalence of the disease in the general population and the heterogeneity of the various cancer types that fall under the ovarian cancer designation. A practical test for early detection will require both high sensitivity and high specificity to balance reducing the number of cancer deaths with minimizing surgical interventions for false positive screens. The technology must be cost-effective to deliver at scale, widely accessible, and relatively noninvasive. Most importantly, a successful early detection test must be effective not only at diagnosing ovarian cancer but also in reducing ovarian cancer deaths. Stepwise or multimodal approaches among the various areas under investigation will likely be required to make early detection a reality.

The relationship of lifetime history of depression on the ovarian tumor immune microenvironment

BACKGROUND

Depression is associated with a higher ovarian cancer risk. Prior work suggests that depression can lead to systemic immune suppression, which could potentially alter the anti-tumor immune response.

METHODS

We evaluated the association of pre-diagnosis depression with features of the anti-tumor immune response, including T and B cells and immunoglobulins, among women with ovarian tumor tissue collected in three studies, the Nurses' Health Study (NHS; n = 237), NHSII (n = 137) and New England Case-Control Study (NECC; n = 215). Women reporting depressive symptoms above a clinically relevant cut-point, antidepressant use, or physician diagnosis of depression at any time prior to diagnosis of ovarian cancer were considered to have pre-diagnosis depression. Multiplex immunofluorescence was performed on tumor tissue microarrays to measure immune cell infiltration. In pooled analyses, we estimated odds ratios (OR) and 95% confidence intervals (CI) for the positivity of tumor immune cells using a beta-binomial model comparing those with and without depression. We used Bonferroni corrections to adjust for multiple comparisons.

RESULTS

We observed no statistically significant association between depression status and any immune markers at the Bonferroni corrected p-value of 0.0045; however, several immune markers were significant at a nominal p-value of 0.05. Specifically, there were increased odds of having recently activated cytotoxic (CD3+CD8+CD69+) and exhausted-like T cells (CD3+Lag3+) in tumors of women with vs. without depression (OR = 1.36, 95 %CI = 1.09-1.69 and OR = 1.24, 95 %CI = 1.01-1.53, respectively). Associations were comparable when considering high grade serous tumors only (comparable ORs = 1.33, 95 %CI = 1.05-1.69 and OR = 1.25, 95 %CI = 0.99-1.58, respectively). There were decreased odds of having tumor infiltrating plasma cells (CD138+) in women with vs. without depression (OR = 0.54, 95 %CI = 0.33-0.90), which was similar among high grade serous carcinomas, although not statistically significant. Depression was also related to decreased odds of having naïve and memory B cells (CD20+: OR = 0.54, 95 %CI = 0.30-0.98) and increased odds of IgG (OR = 1.22, 95 %CI = 0.97-1.53) in high grade serous carcinomas.

CONCLUSION

Our results provide suggestive evidence that depression may influence ovarian cancer outcomes through changes in the tumor immune microenvironment, including increasing T cell activation and exhaustion and reducing antibody-producing B cells. Further studies with clinical measures of depression and larger samples are needed to confirm these results.

Associations between prediagnostic aspirin use and ovarian tumor gene expression

BACKGROUND

Aspirin use has been associated with reduced ovarian cancer risk, yet the underlying biological mechanisms are not fully understood. To gain mechanistic insights, we assessed the association between prediagnosis low and regular-dose aspirin use and gene expression profiles in ovarian tumors.

METHODS

RNA sequencing was performed on high-grade serous, poorly differentiated, and high-grade endometrioid ovarian cancer tumors from the Nurses' Health Study (NHS), NHSII, and New England Case-Control Study (n = 92 cases for low, 153 cases for regular-dose aspirin). Linear regression identified differentially expressed genes associated with aspirin use, adjusted for birth decade and cohort. False discovery rates (FDR) were used to account for multiple testing and gene set enrichment analysis was used to identify biological pathways.

RESULTS

No individual genes were significantly differentially expressed in ovarian tumors in low or regular-dose aspirin users accounting for multiple comparisons. However, current versus never use of low-dose aspirin was associated with upregulation of immune pathways (e.g., allograft rejection, FDR = 5.8 × 10-10 ; interferon-gamma response, FDR = 2.0 × 10-4 ) and downregulation of estrogen response pathways (e.g., estrogen response late, FDR = 4.9 × 10-8 ). Ovarian tumors from current regular aspirin users versus never users were also associated with upregulation in interferon pathways (FDR <1.5 × 10-4 ) and downregulation of multiple extracellular matrix (ECM) architecture pathways (e.g., ECM organization, 4.7 × 10-8 ).

CONCLUSION

Our results suggest low and regular-dose aspirin may impair ovarian tumorigenesis in part via enhancing adaptive immune response and decreasing metastatic potential supporting the likely differential effects on ovarian carcinogenesis and progression by dose of aspirin.

Measurement of Ovarian Tumor Immune Profiles by Multiplex Immunohistochemistry: Implications for Epidemiologic Studies

BACKGROUND

Despite the immunogenic nature of many ovarian tumors, treatment with immune checkpoint therapies has not led to substantial improvements in ovarian cancer survival. To advance population-level research on the ovarian tumor immune microenvironment, it is critical to understand methodologic issues related to measurement of immune cells on tissue microarrays (TMA) using multiplex immunofluorescence (mIF) assays.

METHODS

In two prospective cohorts, we collected formalin-fixed, paraffin-embedded ovarian tumors from 486 cases and created seven TMAs. We measured T cells, including several sub-populations, and immune checkpoint markers on the TMAs using two mIF panels. We used Spearman correlations, Fisher exact tests, and multivariable-adjusted beta-binomial models to evaluate factors related to immune cell measurements in TMA tumor cores.

RESULTS

Between-core correlations of intratumoral immune markers ranged from 0.52 to 0.72, with more common markers (e.g., CD3+, CD3+CD8+) having higher correlations. Correlations of immune cell markers between the whole core, tumor area, and stromal area were high (range 0.69-0.97). In multivariable-adjusted models, odds of T-cell positivity were lower in clear cell and mucinous versus type II tumors (ORs, 0.13-0.48) and, for several sub-populations, were lower in older tissue (sample age > 30 versus ≤ 10 years; OR, 0.11-0.32).

CONCLUSIONS

Overall, high correlations between cores for immune markers measured via mIF support the use of TMAs in studying ovarian tumor immune infiltration, although very old samples may have reduced antigenicity.

IMPACT

Future epidemiologic studies should evaluate differences in the tumor immune response by histotype and identify modifiable factors that may alter the tumor immune microenvironment.

Plasma proteomic profiles of pain subtypes in adolescents and young adults with endometriosis

STUDY QUESTION

What are the similarities and differences in the systemic proteomic profiles by endometriosis-associated pain subtypes among adolescents and young adults with endometriosis?

SUMMARY ANSWER

Endometriosis-associated pain subtypes exhibited distinct plasma proteomic profiles.

WHAT IS KNOWN ALREADY

Endometriosis patients, especially those diagnosed in adolescents and young adults, are often plagued by various pain symptoms. However, it is not clear what biological processes underlie this heterogeneity.

STUDY DESIGN, SIZE, DURATION

We conducted a cross-sectional analysis using data and plasma samples from 142 adolescent or young adult participants of the Women's Health Study: From Adolescence to Adulthood cohort with laparoscopically confirmed endometriosis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We measured 1305 plasma protein levels by SomaScan. We classified self-reported endometriosis-associated pain into subtypes of dysmenorrhea, acyclic pelvic pain, life impacting pelvic pain, bladder pain, bowel pain, and widespread pain phenotype. We used logistic regression to calculate the odds ratios and 95% confidence intervals for differentially expressed proteins, adjusting for age, BMI, fasting status, and hormone use at blood draw. Ingenuity Pathway Analysis identified enriched biological pathways.

MAIN RESULTS AND THE ROLE OF CHANCE

Our study population consisted mainly of adolescents and young adults (mean age at blood draw = 18 years), with nearly all (97%) scored as rASRM stage I/II at laparoscopic diagnosis of endometriosis, which is a common clinical presentation of endometriosis diagnosed at a younger age. Pain subtypes exhibited distinct plasma proteomic profiles. Multiple cell movement pathways were downregulated in cases with severe dysmenorrhea and life impacting pelvic pain compared to those without (P < 7.5×10-15). Endometriosis cases with acyclic pelvic pain had upregulation of immune cell adhesion pathways (P < 9.0×10-9), while those with bladder pain had upregulation of immune cell migration (P < 3.7×10-8) and those with bowel pain had downregulation (P < 6.5×10-7) of the immune cell migration pathways compared to those without. Having a wide-spread pain phenotype involved downregulation of multiple immune pathways (P < 8.0×10-10).

LIMITATIONS, REASONS FOR CAUTION

Our study was limited by the lack of an independent validation cohort. We were also only able to explore any presence of a pain subtype and could not evaluate multiple combinations by pain subtypes. Further mechanistic studies are warranted to elucidate the differences in pathophysiology by endometriosis-pain subtype.

WIDER IMPLICATIONS OF THE FINDINGS

The observed variation in plasma protein profiles by pain subtypes suggests different underlying molecular mechanisms, highlighting the need for potential consideration of pain subtypes for effectively treating endometriosis patients presenting with various pain symptoms.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Department of Defense W81XWH1910318 and the 2017 Boston Center for Endometriosis Trainee Award. Financial support for establishment of and data collection within the A2A cohort were provided by the J. Willard and Alice S. Marriott Foundation. N.S., A.F.V., S.A.M., and K.L.T. have received funding from the Marriott Family Foundation. C.B.S. is funded by an R35 MIRA Award from NIGMS (5R35GM142676). S.A.M. and K.L.T. are supported by NICHD R01HD094842. S.A.M. reports serving as an advisory board member for AbbVie and Roche, Field Chief Editor for Frontiers in Reproductive Health, personal fees from Abbott for roundtable participation; none of these are related to this study. Other authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Abstract 3008: Association between distress and the tumor immune microenvironment in women with ovarian cancer

Various forms of distress, most notably depression, increase ovarian cancer risk. Prior work suggests depression can lead to systemic immune suppression; moreover, after ovarian cancer diagnosis, ongoing depression can lower tumor T cell infiltration. Here, we evaluated the relationship between pre-diagnosis depression and the ovarian tumor immune microenvironment.

Analyses were conducted among women with ovarian cancer in the Nurses’ Health Study (NHS; n=250), NHSII (n=122) and New England Case-Control Study (NEC; n=215). Self-report of depressive symptoms, antidepressant use, or physician diagnosis were used to define depression status. Multiplex immunofluorescence assays were performed on tumor tissue microarrays to measure infiltration of T cells, immune checkpoints, B cells, and immunoglobulins in the tumor area. In pooled analyses, we estimated odds ratios (OR) and 95% confidence intervals (CI) for positivity of tumor immune cells using a beta-binomial model within a repeated measures framework comparing those with and without depression.

Depression was not associated with abundance of CD3+ T cells, CD3+CD8+ cytotoxic T cells, or CD3+CD4+ T helper cells. However, we observed significantly increased odds of having recently activated cytotoxic (CD3+CD8+CD69+) and exhausted T cells (CD3+Lag3+) in tumors of women with vs. without depression (OR=1.34, 95%CI=1.08-1.65 and OR=1.25, 95%CI=1.02-1.53, respectively). Associations were comparable considering only high grade serous tumors (comparable ORs=1.31, 95%CI=1.04-1.65 and OR=1.25, 95%CI=1.00-1.56, respectively). No associations were observed for total B cells (CD19+) and naïve or memory B cells (CD20+). However, there were significantly decreased odds of having tumor infiltrating plasma cells (CD138+) in women with vs. without depression (OR=0.54, 95%CI=0.33-0.89). Among high grade serous carcinomas, the association with plasma cells was similar, though not statistically significant, and depression was related to decreased odds of having naïve and memory B cells (OR=0.56, 95%CI=0.32-0.97) and increased odds of IgG (OR=1.26, 95%CI=1.01-1.58).

Unexpectedly, we observed that immune cells indicative of T cell activation were higher in ovarian tumors of depressed vs. non-depressed women. This may be due to increased inflammation in women with depressive symptomology. Conversely, analyses of plasma cells suggested a reduced adaptive tumor immune response for women with vs. without depression. These results suggest depression may influence ovarian cancer outcomes through changes in the tumor immune microenvironment and that interventions to improve distress in ovarian cancer patients may be a potential strategy to improve outcomes.

Citation Format: Cassandra A. Hathaway, Mary K. Townsend, Jose R. Conejo-Garcia, Brooke L. Fridley, Carlos Moran Segura, Jonathan V. Nguyen, Naoko Sasamoto, Daryoush Saeed-Vafa, Kathryn L. Terry, Laura D. Kubzansky, Shelley S. Tworoger. Association between distress and the tumor immune microenvironment in women with ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3008.

Abstract 3017: Breastfeeding and ovarian cancer risk by tumor immune profiles

Introduction: Breastfeeding is associated with decreased ovarian cancer risk, yet the biological mechanisms are not fully understood. We conducted an agnostic investigation of tumor immune profiles to better understand the role of the tumor microenvironment in the protective association between breastfeeding and ovarian cancer risk.

Methods: Multiplex immunofluorescence was used to measure the abundance of T cells and B cells in ovarian tumor samples on tissue microarrays from the Nurses’ Health Study (NHS; n=337), NHSII (n=127), and New England Case Control Study (NECC; n=214). We averaged the percent of cells within the tumor epithelium that were positive for the immune cell of interest across 3 cores per tumor and categorized tumors as having high or low immune cell abundance based on the median value across all tumors. Controls were non-cases and did not provide tissue samples (n=2,045). Self-reported history of breastfeeding was used to define ever/never and total duration of breastfeeding. Polytomous logistic regression models adjusted for age, birth cohort, race, parity, oral contraception use, and study, was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for breastfeeding and ovarian cancer risk by immune cell level.

Results: Overall, breastfeeding was associated with a reduced risk of tumors with low, but not high, subtypes of T cell abundance. Among parous women, history of ever breastfeeding decreased the risk of tumors with low helper T cells (CD3+CD4+; ORlow: 0.56, 95% CI: 0.41-0.77), but not high helper T cells (ORhigh: 0.85, 95% CI: 0.63-1.35; p-het=0.06). For total B cells (CD19+), having ever breastfed was associated with decreased risk of both low (ORlow: 0.64, 95% CI: 0.47-0.87) and high abundance in the tumor (ORhigh: 0.70, 95% CI: 0.62-0.96, p-het=0.67) among parous women. Similar results were observed for CD138+ plasma cells (ORlow:0.76, 95% CI: 0.56-0.99; ORhigh: 0.59, 95% CI: 0.37-0.94; p-het=0.34). Longer duration of breastfeeding was associated with decreased risk of developing tumors with low abundance of total B cells (CD19+, p-trend=0.02) and regulatory B cells (CD19+TNFR2+, p-trend=0.05), but not high abundance of CD19+ or CD19+TNFR2+ (p-het=0.01 and 0.03, respectively).

Conclusion: These results indicate that among parous women breastfeeding is associated with reduced risk of ovarian tumors with low infiltration of helper T cells while no heterogeneity was observed for risk by total B cells or plasma cells. Longer breastfeeding duration was associated with reduced risk of tumors low in regulatory B cells (CD19+TNFR+) with a dose-dependent response. Together, these results suggest breastfeeding may play a role in the activation of the tumor immune response. Further efforts are ongoing to disentangle the relationships between breastfeeding and parity with the tumor immune microenvironment.

Citation Format: Jennifer Mongiovi, Mary Townsend, Allison Vitonis, Ana Babic, Jonathan Hecht, Jose Conejo-Garcia, Brooke Fridley, Shelley Tworoger, Kathryn Terry, Naoko Sasamoto. Breastfeeding and ovarian cancer risk by tumor immune profiles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3017.

Abstract 3024: Development of a plasma metabolomics prediction model for early detection of ovarian cancer using prospectively collected blood samples in two independent cohorts

Background: Ovarian cancer has poor survival due to more than 60% of patients being diagnosed at advanced stage. Therefore, discovery of novel, non-invasive early detection biomarkers has high potential to improve outcomes. Here, using prospectively collected blood samples, we developed a model using plasma metabolite levels to discriminate ovarian cancer cases from controls and applied it to an independent dataset.

Method: We examined 251 lipid and lipid-related metabolites measured using a liquid chromatography tandem mass spectrometry method (Broad Institute, Cambridge, MA) in plasma collected up to three years prior to ovarian cancer diagnosis and controls matched on age, blood collection characteristics, and menopausal status at blood draw and diagnosis in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO; n=100, testing dataset) and the Nurses’ Health Studies (NHS; n=98, replication dataset). We used a paired t-test to identify metabolites with a significant difference (p&lt;0.05) between ovarian cancer cases and controls. Then we used LASSO to identify metabolites that best discriminated ovarian cancer cases from controls in PLCO. We estimated the area under the receiver operating characteristic curve (AUC) and 95% confidence interval (CI) to assess model performance in discriminating ovarian cancer cases from controls when adding the selected metabolite score to a model based on CA125 using the clinical cutoff of 35U/mL, in PLCO and NHS.

Results: Ten metabolites were significantly different between ovarian cancer cases and controls (p&lt;0.05) in PLCO. LASSO selected 9 of the 10 metabolites into a prediction model including CA125 [i.e., C16:0 cholesteryl ester (CE), C22:6 CE, C30:0 phosphatidyl choline (PC), C32:1 PC, C40:10 PC, C38:2 phosphatidylethanolamine, C45:0 triglyceride, acetaminophen, 4-hydroxyhippurate]. In PLCO, adding a metabolite score derived from the 9 LASSO selected metabolites to a model with CA125 alone resulted in a significant (p&lt;0.01) increase in AUC (95%CI) from 0.66(0.59-0.72) to 0.87(0.80-0.94). In NHS, adding the metabolite score to a model with CA125 alone also resulted in a significant (p=0.05) increase in AUC from 0.63(0.56-0.71) to 0.72(0.61-0.83).

Conclusion: Using prospectively collected blood samples, we created a metabolite score which significantly increased the AUC compared to a model with CA125 alone and discriminated ovarian cancer cases from controls in the training dataset (PLCO). We replicated our findings in an independent test dataset (NHS). Further investigations assessing the performance of other statistical methods for replication (e.g., bootstrapping) and model building (e.g., random forest) are ongoing. These results suggest plasma metabolites represent promising novel early detection biomarkers for ovarian cancer.

Citation Format: Oana A. Zeleznik, Julian Avila-Pacheco, Daniel W. Cramer, Britton Trabert, Clary B. Clish, Shelley Tworoger, Kathryn L. Terry, Naoko Sasamoto. Development of a plasma metabolomics prediction model for early detection of ovarian cancer using prospectively collected blood samples in two independent cohorts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3024.

Trends in pelvic pain symptoms over 2 years of follow-up among adolescents and young adults with and without endometriosis

ABSTRACT

We described trends in pelvic pain characteristics over 2 years of follow-up among adolescents and adults with and without endometriosis participating in the longitudinal observational cohort of the Women's Health Study: From Adolescence to Adulthood, using data reported at baseline and at years 1 and 2 of follow-up. Participants completed a questionnaire at baseline (between November 2012 and May 2019) and annually thereafter that included validated measures of severity, frequency, and life interference of dysmenorrhea, acyclic pelvic pain, and dyspareunia. Our study population included 620 participants with surgically confirmed endometriosis (rASRM stage I/II = 95%) and 671 community-based and hospital-based controls, with median age = 19 and 24 years, respectively. The proportion reporting hormone use varied across the 3 years ranging from 88% to 92% for cases and 56% to 58% for controls. At baseline, endometriosis cases were more likely to report severe, frequent, and life-interfering dysmenorrhea, acyclic pelvic pain, and dyspareunia compared with controls. Among cases, frequency and severity of dysmenorrhea and dyspareunia were relatively static across 2 years. However, acyclic pelvic pain improved. Severe acyclic pain decreased from 69% at baseline to 46% at year 2. Daily pain decreased from 28% to 14%, and life interference from 68% to 38%. Trends among controls remained fairly stable across 2 years. Among endometriosis cases who completed the questionnaire at all 3 time points, 18% reported persistent, severe acyclic pelvic pain at all 3 time points. Over time, different trends were observed by pelvic pain type among endometriosis cases and controls, supporting the importance of assessing multidimensional features of pelvic pain.

CCNE1 and survival of patients with tubo-ovarian high-grade serous carcinoma: An Ovarian Tumor Tissue Analysis consortium study

BACKGROUND

Cyclin E1 (CCNE1) is a potential predictive marker and therapeutic target in tubo-ovarian high-grade serous carcinoma (HGSC). Smaller studies have revealed unfavorable associations for CCNE1 amplification and CCNE1 overexpression with survival, but to date no large-scale, histotype-specific validation has been performed. The hypothesis was that high-level amplification of CCNE1 and CCNE1 overexpression, as well as a combination of the two, are linked to shorter overall survival in HGSC.

METHODS

Within the Ovarian Tumor Tissue Analysis consortium, amplification status and protein level in 3029 HGSC cases and mRNA expression in 2419 samples were investigated.

RESULTS

High-level amplification (>8 copies by chromogenic in situ hybridization) was found in 8.6% of HGSC and overexpression (>60% with at least 5% demonstrating strong intensity by immunohistochemistry) was found in 22.4%. CCNE1 high-level amplification and overexpression both were linked to shorter overall survival in multivariate survival analysis adjusted for age and stage, with hazard stratification by study (hazard ratio [HR], 1.26; 95% CI, 1.08-1.47, p = .034, and HR, 1.18; 95% CI, 1.05-1.32, p = .015, respectively). This was also true for cases with combined high-level amplification/overexpression (HR, 1.26; 95% CI, 1.09-1.47, p = .033). CCNE1 mRNA expression was not associated with overall survival (HR, 1.00 per 1-SD increase; 95% CI, 0.94-1.06; p = .58). CCNE1 high-level amplification is mutually exclusive with the presence of germline BRCA1/2 pathogenic variants and shows an inverse association to RB1 loss.

CONCLUSION

This study provides large-scale validation that CCNE1 high-level amplification is associated with shorter survival, supporting its utility as a prognostic biomarker in HGSC.

Predictors of residual disease after debulking surgery in advanced stage ovarian cancer

Objective

Optimal debulking with no macroscopic residual disease strongly predicts ovarian cancer survival. The ability to predict likelihood of optimal debulking, which may be partially dependent on tumor biology, could inform clinical decision-making regarding use of neoadjuvant chemotherapy. Thus, we developed a prediction model including epidemiological factors and tumor markers of residual disease after primary debulking surgery.

Methods

Univariate analyses examined associations of 11 pre-diagnosis epidemiologic factors (n=593) and 24 tumor markers (n=204) with debulking status among incident, high-stage, epithelial ovarian cancer cases from the Nurses' Health Studies and New England Case Control study. We used Bayesian model averaging (BMA) to develop prediction models of optimal debulking with 5x5-fold cross-validation and calculated the area under the curve (AUC).

Results

Current aspirin use was associated with lower odds of optimal debulking compared to never use (OR=0.52, 95%CI=0.31-0.86) and two tissue markers, ADRB2 (OR=2.21, 95%CI=1.23-4.41) and FAP (OR=1.91, 95%CI=1.24-3.05) were associated with increased odds of optimal debulking. The BMA selected aspirin, parity, and menopausal status as the epidemiologic/clinical predictors with the posterior effect probability ≥20%. While the prediction model with epidemiologic/clinical predictors had low performance (average AUC=0.49), the model adding tissue biomarkers showed improved, but weak, performance (average AUC=0.62).

Conclusions

Addition of ovarian tumor tissue markers to our multivariable prediction models based on epidemiologic/clinical data slightly improved the model performance, suggesting debulking status may be in part driven by tumor characteristics. Larger studies are warranted to identify those at high risk of poor surgical outcomes informing personalized treatment.

Abstract P030: Prospective analysis of plasma metabolites for early detection of high-grade serous ovarian cancer

Background: Ovarian cancer has poor prognosis due to &gt;60% of the patients being diagnosed at late-stage. However, there is currently no ovarian cancer biomarker appropriate for screening. This may be, in part, due to many prior studies using clinical samples obtained at the time of diagnosis for biomarker discovery. Here, we sought to discover novel plasma metabolomic biomarkers for ovarian cancer early detection using prospectively collected blood samples. Methods: We examined 250 plasma metabolites in 93 high-grade serous ovarian cancer (HGSOC) cases with blood drawn up to five years prior to diagnosis and 93 matched controls in the prospective Nurses’ Health Studies and Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We also measured metabolites in 40 early-stage HGSOC cases with blood collected at diagnosis and 40 matched controls in a hospital-based study. We used conditional logistic regression to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of the association between one standard deviation increase in metabolite levels and ovarian cancer risk, and used metabolite set enrichment analysis (MSEA) to identify metabolite group associations. False discovery rate (FDR) was used to correct for multiple testing. For the prospectively collected blood samples, we conducted analyses by time between blood draw and diagnosis. Results: Plasma metabolites associated with ovarian cancer in blood samples collected prospectively were different than in blood samples collected at diagnosis of early-stage disease compared to controls. There were 45 individual metabolites associated with early-stage disease (FDR&lt;0.05), and none of these metabolites were associated with ovarian cancer in the prospectively collected blood samples (FDR&lt;0.05). There were 10 metabolites associated with ovarian cancer diagnosed within 3 years of blood collection (p&lt;0.05), including 7 lipid metabolites (2 lysophosphatidylcholines, 2 diglycerides, 1 phosphatidylcholine, 1 cholesteryl esters, 1 phosphatidylethanolamines) that were inversely associated with ORs ranging from 0.61-0.66. Interestingly, the direction of association remained similar when restricting to cases with blood collected up to 2 years and 1 year prior to diagnosis, and the magnitude of association generally became stronger for cases closer to diagnosis. Similarly, distinct profiles were observed in MSEA, with diglycerides being inversely associated with ovarian cancer diagnosis in prospectively collected blood samples (FDR ranging from &lt;0.05 to &lt;0.20) and positively associated in blood collected at early-stage disease diagnosis (FDR&lt;0.05).Conclusion: Our results revealed plasma metabolomic profiles differ between prospectively collected blood samples up to 3 years prior to diagnosis and blood samples collected at time of diagnosis, even for early-stage disease, suggesting the use of prospectively collected blood samples may discover promising novel early detection biomarkers for ovarian cancer.

Citation Format: Naoko Sasamoto, Oana A. Zeleznik, Allison F. Vitonis, Daniel W. Cramer, Julian Avila-Pacheco, Clary B. Clish, Britton Trabert, Shelley S. Tworoger, Kathryn L. Terry. Prospective analysis of plasma metabolites for early detection of high-grade serous ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P030.

Is early-onset cancer an emerging global epidemic? Current evidence and future implications

Over the past several decades, the incidence of early-onset cancers, often defined as cancers diagnosed in adults <50 years of age, in the breast, colorectum, endometrium, oesophagus, extrahepatic bile duct, gallbladder, head and neck, kidney, liver, bone marrow, pancreas, prostate, stomach and thyroid has increased in multiple countries. Increased use of screening programmes has contributed to this phenomenon to a certain extent, although a genuine increase in the incidence of early-onset forms of several cancer types also seems to have emerged. Evidence suggests an aetiological role of risk factor exposures in early life and young adulthood. Since the mid-20th century, substantial multigenerational changes in the exposome have occurred (including changes in diet, lifestyle, obesity, environment and the microbiome, all of which might interact with genomic and/or genetic susceptibilities). However, the effects of individual exposures remain largely unknown. To study early-life exposures and their implications for multiple cancer types will require prospective cohort studies with dedicated biobanking and data collection technologies. Raising awareness among both the public and health-care professionals will also be critical. In this Review, we describe changes in the incidence of early-onset cancers globally and suggest measures that are likely to reduce the burden of cancers and other chronic non-communicable diseases.

Comparative Study of Postoperative Analgesic Effects of Intraoperative Levobupivacaine Local Infiltration Anesthesia and Transversus Abdominis Plane Block Following Gynecologic Laparoscopy

Objectives

We aim to assess the postoperative analgesic effect of intraoperative levobupivacaine local infiltration anesthesia (LA) and transversus abdominis plane (TAP) block in gynecologic laparoscopy.

Materials and Methods

We conducted a retrospective analysis on the data of 260 patients treated by gynecologic laparoscopy (adnexal surgery, hysterectomy, and myomectomy) between January 2019 and December 2020 at Minoh City Hospital, Osaka Japan. Patients were divided into two groups: intraoperative LA group and TAP block group. We assessed clinical characteristics, surgical results, postoperative numerical rating scale (NRS) pain scores, and the frequency of analgesic use up to 24 h after surgery in overall and by each type of surgery. Pearson's χ² test, Fisher's exact test, and Wilcoxon/Kruskal-Wallis test were used for statistical analysis. Multiple regression analysis was used for multivariate analysis.

Results

NRS pain score was statistically significantly higher in the LA group than in the TAP group 1 h after surgery in overall (P = 0.04), with NRS difference of 0.4 which was not clinically significant. No significant differences were observed in NRS pain scores at 3, 6, 12, and 24 h after surgery or in the frequency of analgesic use up to 24 h after surgery in overall and by type of surgery. Endometriosis was associated with increased postoperative pain at 1 h after surgery in adnexal surgeries (P = 0.04) and suggestive for all surgeries. Younger age was related to more frequency of analgesic use up to 24 h after surgery in overall, adnexal surgeries, and hysterectomy.

Conclusion

Intraoperative levobupivacaine LA may have similar postoperative analgesic effects as TAP block in gynecologic laparoscopy.

Diagnostic accuracy of pelvic examination in pelvic inflammatory disease: A meta‐analysis

Background

Pelvic inflammatory disease (PID) is not a mere transient infection. PID can lead to chronic pain, ectopic pregnancy, and infertility. Although the Centers for Disease Control and Prevention have established minimum diagnostic criteria, including pelvic examination, the diagnostic value of pelvic tenderness has recently garnered controversy. Our meta‐analysis aimed to confirm whether pelvic tenderness, cervical motion tenderness, and adnexal tenderness can help diagnose PID.

Methods

We searched for studies reporting the diagnostic test accuracy of pelvic tenderness, cervical motion tenderness, and adnexal tenderness among female patients at risk for PID, using MEDLINE, EMBASE, CENTRAL, CINAHL, Google, and Google Scholar through May 25th, 2022. After quality assessment using QUADAS‐2, we performed data synthesis using a bivariate random effect model and Bayesian hierarchical summary receiver operating characteristic model. We then conducted sensitivity analysis excluding studies with non‐PID cases.

Results

The literature search produced 6769 articles. After quality assessment, 14 studies and their 2808 participants were eligible for synthesis on pelvic tenderness. Laparoscopy, either alone or in combination, was the most frequent reference standard. The main results for pelvic tenderness sensitivity and specificity were 0.81, 95% confidence interval (CI) [0.67–0.90] and 0.40, 95% CI [0.25–0.57], respectively. Sensitivity and specificity were 0.72, 95% CI [0.57–0.83] and 0.50, 95% CI [0.34–0.66], for cervical motion tenderness, and 0.87 [0.64–0.96] and 0.27, 95% CI [0.12–0.52] for adnexal tenderness, respectively.

Conclusions

Our meta‐analysis suggests that pelvic tenderness assessed by pelvic examination may be useful for PID examination with moderate‐to‐high sensitivity, whereas clinicians should be aware of the diagnostic significance of pelvic tenderness.

Stability and reproducibility of proteomic profiles in epidemiological studies: comparing the Olink and SOMAscan platforms

Limited data exist on the performance of high-throughput proteomics profiling in epidemiological settings, including the impact of specimen collection and within-person variability over time. Thus, the Olink (972 proteins) and SOMAscan7Kv4.1 (7322 proteoforms of 6596 proteins) assays were utilized to measure protein concentrations in archived plasma samples from the Nurses' Health Studies and Health Professionals Follow-Up Study. Spearman's correlation coefficients (r) and intraclass correlation coefficients (ICCs) were used to assess agreement between (1) 42 triplicate samples processed immediately, 24-h or 48-h after blood collection from 14 participants; and (2) 80 plasma samples from 40 participants collected 1-year apart. When comparing samples processed immediately, 24-h, and 48-h later, 55% of assays had an ICC/r ≥ 0.75 and 87% had an ICC/r ≥ 0.40 in Olink compared to 44% with an ICC/r ≥ 0.75 and 72% with an ICC/r ≥ 0.40 in SOMAscan7K. For both platforms, >90% of the assays were stable (ICC/r ≥ 0.40) in samples collected 1-year apart. Among 817 proteins measured with both platforms, Spearman's correlations were high (r > 0.75) for 14.7% and poor (r < 0.40) for 44.8% of proteins. High-throughput proteomics profiling demonstrated reproducibility in archived plasma samples and stability after delayed processing in epidemiological studies, yet correlations between proteins measured with the Olink and SOMAscan7K platforms were highly variable.

Circulating proteomic profiles associated with endometriosis in adolescents and young adults

STUDY QUESTION

What are the systemic molecular profiles of endometriosis diagnosed in adolescents and young adults?

SUMMARY ANSWER

Significant enrichment and increased activation of proteins related to angiogenesis and cell migration pathways were observed in endometriosis cases compared to controls (P-value < 2.4 × 10-8).

WHAT IS KNOWN ALREADY

Little is known about the pathophysiology of adolescent endometriosis despite the fact that over 50% of adults with endometriosis report onset of severe pelvic pain during adolescence.

STUDY DESIGN, SIZE, DURATION

A cross-sectional analysis using data on 142 laparoscopically confirmed endometriosis cases and 74 controls from the observational longitudinal cohort of Women's Health Study: From Adolescence to Adulthood (A2A).

PARTICIPANTS/MATERIALS, SETTING, METHODS

We measured 1305 plasma protein levels using the validated, multiplex aptamer-based proteomics discovery platform, SOMAscan. We calculated odds ratios and 95% CIs using logistic regression adjusting for age, BMI, fasting status and hormone use at blood draw for differentially expressed proteins (P < 0.05). Ingenuity Pathway Analysis and STRING analysis were performed to identify biological pathways and protein interactions. We also examined proteins and pathways associated with superficial peritoneal lesion colors (i.e. red, vascularized, white, blue/black, brown).

MAIN RESULTS AND THE ROLE OF CHANCE

Average age at blood draw was 18 years for endometriosis cases and 22 years for controls. We identified 63 proteins associated with endometriosis with type-I error set at 0.05, and absolute fold change >1.2, revealing significant enrichment of dysregulated proteins in biological pathways associated with endometriosis. Increased activation of pathways related to angiogenesis and cell migration was observed in plasma from endometriosis cases compared to controls (P-value < 2.4 × 10-8). Furthermore, when we examined proteins and pathways associated with lesion colors, vascularized lesions were associated with upregulation of pathways related to immune cell migration/activation and inflammation, whereas white, blue/black and brown lesions were associated with downregulation of these pathways.

LIMITATIONS, REASONS FOR CAUTION

Validation of our results in independent datasets and mechanistic studies are warranted to further our understanding of the pathophysiological characteristics of this common but understudied patient population.

WIDER IMPLICATIONS OF THE FINDINGS

To our knowledge, this was the first study to comprehensively examine circulating proteins in predominantly adolescents and young adult women with and without endometriosis. Results from this study provide novel biological insight that will build toward further research to elucidate endometriosis pathophysiology during the earlier course of the disease trajectory.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Department of Defense (W81XWH1910318) and the 2017 Boston Center for Endometriosis Trainee Award. Financial support for establishment of and data collection within the A2A cohort were provided by the J. Willard and Alice S. Marriott Foundation. N.S., A.F.V., S.A.M., K.L.T. have received funding from Marriott Family Foundation. S.A.M. and K.L.T. are supported by NICHD (R01 HD94842). S.A.M. serves as an advisory board member for AbbVie and Roche; neither are related to this study. The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Abstract 277: High agreement between immune profiling assays on the detection of infiltrating immune cells in ovarian tumor tissue

Detecting immune cells and estimating their heterogeneity in the tumor microenvironment (TME) is critical to inform assessments of cancer prognosis and response to immunotherapies. Many immune activity assays to detect immune cells are available, including multiplex immunofluorescence (mIF) of tissue slices to assess co-localization of immune cell markers and traditional immunohistochemistry (IHC) staining. More recently, statistical approaches to define cell types from RNAseq data (e.g., deconvolution, gene set enrichment) have been widely adopted due to the wide availability of transcriptomics profiles. Here, we interrogated the level of agreement between immune cells in the ovarian TME assessed by mIF (Vectra images processed via InForm/Halo), IHC, and deconvoluted whole exome RNAseq. We leveraged data from epithelial ovarian tumor cores embedded in tissue microarrays from participants in the Nurses’ Health Study I and II and the New England Case-Control Study (mIF, n=668 women; IHC, n=467; RNAseq, n=241). To explore agreement between technologies, we calculated the overall and compartment-specific percentages of cells positive for mIF markers CD3, CD4, CD8, CD19, CD20, CD138 and FOXP3, including cell specific phenotypes based on these markers. For IHC, a pathologist generated scores based on proportion of positive cells and/or aggregation into four levels (0, 1, 2, or 3) for markers CD8, CD68, and CD163. Deconvolution of transcriptomic profiles was performed with CIBERSORT (22 cell types) and xCell (64 cell types). Spearman correlation between technologies for cell specific markers (i.e., cytotoxic T cells, regulatory T cells (Tregs), B cells, macrophages, monocytes, among others) was used to assess agreement. We observed that detection of CD8+ and CD3+CD8+ cells from mIF (cytotoxic T cells) was consistent with the other assays (r &gt;0.25), and the highest correlation was observed with IHC CD8+ cells (r=0.52). For deconvoluted transcriptomic predictions, CD8 T cells (xCell, CIBERSORT), and memory CD8 T cells (xCell) showed high agreement with mIF CD8+ and CD3+CD8+ cells (r=0.25 to 0.48). CD4+ and CD3+CD4+ cells detected with mIF also showed correlation with xCell CD4 memory T cells (r=0.25 to 0.34). As expected, only general class B cells from xCell showed agreement with mIF CD20+ cells (r=0.35). In addition, xCell Tregs correlated with mIF FOXP3+ cells (r=0.34). These results highlight the importance of considering the predictive power of immunological assays for the study of the TME. Compared to mIF, the robustness of deconvoluted RNAseq data varies with the cell type being predicted. Finally, RNAseq should be considered a complementary technology to staining of archival tissues given that the former does conserve spatial distribution of cell types.

Citation Format: Oscar E. Ospina, Mary K. Townsend, Tianyi Wang, Naoko Sasamoto, Paul Stewart, Jose Conejo-Garcia, Kathryn Terry, Shelley S. Tworoger, B L. Fridley. High agreement between immune profiling assays on the detection of infiltrating immune cells in ovarian tumor tissue [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 277.

Abstract 2253: Plasma metabolomic profiles associated with early and late-stage high-grade serous ovarian cancer

Background: Ovarian cancer has poor survival due to more than 60% of patients being diagnosed at advanced stage. Therefore, discovery of novel, non-invasive early detection biomarkers has high potential to improve survival. Here, we identified plasma metabolomic profiles associated with early-stage and late-stage high-grade serous ovarian cancer (HGSOC), the most common histotype.

Method: We examined 197 lipid and lipid-related metabolites measured using a validated, liquid chromatography tandem mass spectrometry method (Broad Institute, Cambridge, MA) in plasma collected prior to surgery from 40 early-stage and 40 late-stage HGSOC patients and 40 population-based controls matched on age, year, and menopausal status at blood draw. We used multivariable logistic regression, adjusted for matching factors, tubal ligation, oral contraceptive use, and parity, to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of ovarian cancer risk per 1 standard deviation increase in probit-transformed metabolite levels. We used Metabolite Set Enrichment Analysis (MSEA) to identify metabolite groups. We accounted for testing multiple correlated hypotheses using the number of effective tests (NEF) or false discovery rate (FDR).

Results: Compared to controls, there were 34 metabolites associated with early-stage HGSOC and 88 metabolites associate with late-stage HGSOC (unadjusted p-value&lt;0.05). All metabolites associated with risk of early-stage HGSOC and majority (n=80, 90%) of the metabolites associated with risk of late-stage HGSOC were inversely associated with ORs ranging from 0.28 to 0.48 for early-stage and 0.08 to 0.59 for late-stage HGSOC. Interestingly, the direction of association across all these metabolites were similar in both early-stage and late-stage HGSOC, with stronger effect estimates for late-stage HGSOC. After multiple testing correction, there were 9 statistically significant metabolites associated with risk of late-stage HGSOC (NEF p-value&lt;0.05) whereas no individual metabolites remained associated with risk of early-stage HGSOC. MSEA revealed similar patterns of association compared to controls across the 11 lipid groups assessed in early and late-stage HGSOC cases. Metabolite groups of phosphatidylethanolamine plasmalogens and triglycerides were inversely associated with early-stage HGSOC compared to controls (FDR p-value&lt;0.05). Metabolite groups of phosphatidylethanolamine plasmalogens and phosphatidylcholines were inversely, and diglycerides were positively associated with late-stage HGSOC compared to controls (FDR p-value&lt;0.05).

Conclusion: Our results revealed early-stage and late-stage HGSOC having similar plasma metabolomic profiles overall although there were more metabolites that were significantly associated with late-stage HGSOC than early-stage HGSOC compared to population-based controls.

Citation Format: Naoko Sasamoto, Oana A. Zeleznik, Allison F. Vitonis, Daniel W. Cramer, Julian Avila-Pacheco, Clary B. Clish, Shelley S. Tworoger, Kathryn L. Terry. Plasma metabolomic profiles associated with early and late-stage high-grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2253.

Abstract 5887: Association of ovarian tumor immune profiles with overall survival

Despite being immunogenic, high-grade serous ovarian carcinomas (HGSC), the most common histotype, generally are not responsive to immune checkpoint inhibitors. To understand potential reasons for this, we examined associations of tumor-infiltrating B cells and T cells, including sub-populations defined by expression of immune checkpoints and T cell exhaustion markers, with survival in three epidemiologic studies. Analyses included participants in the Nurses’ Health Study (NHS), NHSII, and New England Case-control study who were diagnosed with stage 1-3 HGSC for whom tumor tissue was obtained. B cells (CD19, CD20, CD138), T cells (CD3), and T cell subpopulations (CD3 co-localized with CD8, CD4, PD1, PDL1, LAG3, TIM3) were measured using multiplex immunofluorescence assays performed on tissue microarray slides containing 3 cores per case. For each participant, we summed counts of immune cells infiltrating the tumor and total tumor cells across cores. Counts of immune cell subpopulations were adjusted for the parent cell count using residuals from beta-binomial models. Hazard ratios (HR) and 95% confidence intervals (CI) for overall mortality according to presence/absence or quantiles of immune cells were calculated using Cox proportional hazards regression models adjusting for age at diagnosis, diagnosis year, stage, study, and total tumor cell count. Among 389 women with HGSC, presence vs. absence of CD19+ B cells was suggestively associated with lower mortality (HR 0.79, 95%CI:0.61-1.01); similar associations were observed for CD19-adjusted CD20+ B cells and CD138+ plasma cells (HRs 0.75-0.78, quintile 5 vs. 1).Higher total T cells was associated with improved survival (HR 0.67, 95%CI:0.45-0.99, quintile 5vs. 1). Similar reduced risks were observed with high levels of both CD19+ B cells and CD3+ T cells (HR 0.66) or high levels of one cell type (HRs 0.65-0.75) compared with low levels of both. For the two primary T cell subfractions, lower risk was observed with higher CD3-adjustedCD3+CD8+ cytotoxic T cells (HRs 0.68, 0.73, 0.69, 0.59 for quintiles 2-5 vs. 1), but notCD3+CD4+ helper T cells (HR 0.97, 95%CI: 0.72-1.31, tertile 3 vs. 1). T cells with immune checkpoint markers (PD1, PDL1) and/or markers of T-cell exhaustion (LAG3, TIM3) generally were not associated with mortality or tended to be associated with lower mortality risk, with a significant inverse association observed for CD3-adjusted CD3+PD1+TIM3- cells (HR 0.61,95%CI:0.41-0.92, quintile 5 vs. 1).Overall, higher levels of B cells and CD3+CD8+ T cells in tumor were associated with improved outcomes, consistent with other studies. Congruent with the apparent ineffectiveness of immune checkpoint inhibitors in ovarian cancer, our results do not support that T cells expressing immune checkpoint and/or T cell exhaustion markers are related to worse outcome among women with HGSC. Future analyses will consider multiple cell types simultaneously and the stroma compartment.

Citation Format: Shelley S. Tworoger, Mary K. Townsend, Jose Conejo-Garcia, Brooke L. Fridley, Carlos Moran Segura, Daryoush Saeed-Vafa, Naoko Sasamoto, Kathryn L. Terry. Association of ovarian tumor immune profiles with overall survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5887.

Cohort profile: The Endometriosis pain QUality aftEr Surgical Treatment (EndoQUEST) Study

Endometriosis affects reproductive-aged females and varies considerably in terms of symptom presentation, morphologic features, and treatment response. Most studies investigating symptom recurrence after an endometriosis-related surgery have been conducted among adults. The Endometriosis pain QUality aftEr Surgical Treatment (EndoQUEST) Study was established to assess characteristics and biomarkers that are associated with pain remediation and improved quality of life after an endometriosis-related surgery among adolescents and young adults. This paper describes the EndoQUEST methodology, summarizes baseline descriptive factors, and compares characteristics by participant retention status. We enrolled 100 surgically-confirmed endometriosis participants aged 12–23 years who provided questionnaire data on reproductive and behavioral factors, pain characteristics and quality of life at three time points; before surgery, 6 weeks to 26 weeks after surgery, and 1 year after surgery. Among these 100 participants, 88 provided blood and/or saliva at all three time points, while 12 provided blood and/or saliva samples only before surgery and 6 to 26 weeks after surgery. There was little evidence of lost to follow-up at 1 year after surgery due to pain symptoms, as pain and quality of life characteristics were similar between participants who completed the questionnaire 1 year after surgery and those who did not. Analyses utilizing these longitudinal data will advance personalized treatment decision making for adolescents and young adults with endometriosis.

Lifetime ovulatory years and ovarian cancer gene expression profiles

BACKGROUND

Greater ovulatory years is associated with increased ovarian cancer risk. Although ovulation leads to an acute pro-inflammatory local environment, how long-term exposure to ovulation impacts ovarian carcinogenesis is not fully understood. Thus, we examined the association between gene expression profiles of ovarian tumors and lifetime ovulatory years to enhance understanding of associated biological pathways.

METHODS

RNA sequencing data was generated on 234 invasive ovarian cancer tumors that were high-grade serous, poorly differentiated, or high-grade endometrioid from the Nurses' Health Study (NHS), NHSII, and the New England Case Control Study. We used linear regression to identify differentially expressed genes by estimated ovulatory years, adjusted for birth decade and cohort, overall and stratified by menopausal status at diagnosis. We used false discovery rates (FDR) to account for multiple testing. Gene set enrichment analysis (GSEA) with Cancer Hallmarks, KEGG, and Reactome databases was used to identify biological pathways associated with ovulatory years.

RESULTS

No individual genes were significantly differentially expressed by ovulatory years (FDR > 0.19). However, GSEA identified several pathways that were significantly associated with ovulatory years, including downregulation of pathways related to inflammation and proliferation (FDR < 1.0 × 10-5). Greater ovulatory years were more strongly associated with downregulation of genes related to proliferation (e.g., E2F targets, FDR = 1.53 × 10-24; G2M checkpoints, FDR = 3.50 × 10-22) among premenopausal versus postmenopausal women at diagnosis. The association of greater ovulatory years with downregulation of genes involved in inflammatory response such as interferon gamma response pathways (FDR = 7.81 × 10-17) was stronger in postmenopausal women.

CONCLUSIONS

Our results provide novel insight into the biological pathways that link ovulatory years to ovarian carcinogenesis, which may lead to development of targeted prevention strategies for ovarian cancer.

MCM3 is a novel proliferation marker associated with longer survival for patients with tubo-ovarian high-grade serous carcinoma

Tubo-ovarian high-grade serous carcinomas (HGSC) are highly proliferative neoplasms that generally respond well to platinum/taxane chemotherapy. We recently identified minichromosome maintenance complex component 3 (MCM3), which is involved in the initiation of DNA replication and proliferation, as a favorable prognostic marker in HGSC. Our objective was to further validate whether MCM3 mRNA expression and possibly MCM3 protein levels are associated with survival in patients with HGSC. MCM3 mRNA expression was measured using NanoString expression profiling on formalin-fixed and paraffin-embedded tissue (N = 2355 HGSC) and MCM3 protein expression was assessed by immunohistochemistry (N = 522 HGSC) and compared with Ki-67. Kaplan-Meier curves and the Cox proportional hazards model were used to estimate associations with survival. Among chemotherapy-naïve HGSC, higher MCM3 mRNA expression (one standard deviation increase in the score) was associated with longer overall survival (HR = 0.87, 95% CI 0.81-0.92, p < 0.0001, N = 1840) in multivariable analysis. MCM3 mRNA expression was highest in the HGSC C5.PRO molecular subtype, although no interaction was observed between MCM3, survival and molecular subtypes. MCM3 and Ki-67 protein levels were significantly lower after exposure to neoadjuvant chemotherapy compared to chemotherapy-naïve tumors: 37.0% versus 46.4% and 22.9% versus 34.2%, respectively. Among chemotherapy-naïve HGSC, high MCM3 protein levels were also associated with significantly longer disease-specific survival (HR = 0.52, 95% CI 0.36-0.74, p = 0.0003, N = 392) compared to cases with low MCM3 protein levels in multivariable analysis. MCM3 immunohistochemistry is a promising surrogate marker of proliferation in HGSC.

Presurgical blood metabolites and risk of postsurgical pelvic pain in young patients with endometriosis

OBJECTIVE

To identify metabolites in presurgical blood associated with risk of persistent postsurgical pelvic pain 1 year after endometriosis surgery in adolescent and young adult patients.

DESIGN

Prospective observational study within the Women's Health Study: From Adolescence to Adulthood, a US-based longitudinal cohort of adolescents and women enrolled from 2012-2018.

SETTING

Two tertiary care hospitals.

PATIENT(S)

Laparoscopically confirmed endometriosis patients (n = 180) with blood collected before their endometriosis surgery. Of these, 77 patients additionally provided blood samples 5 weeks to 6 months after their surgery. We measured plasma metabolites using liquid chromatography tandem mass spectrometry, and a total of 390 known metabolites were included in our analysis.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Persistent postsurgical pelvic pain, defined as severe, life-impacting pelvic pain 1 year after endometriosis surgery.

RESULT(S)

Most patients (>95%) were at stage I/II of the revised American Society for Reproductive Medicine classification. Their average age at diagnosis was 18.7 years, with 36% reporting persistent postsurgical pelvic pain. Of the 21 metabolites in presurgical blood that were associated with risk of persistent postsurgical pelvic pain, 19 metabolites, which were mainly lipid metabolites, were associated with increased risk. Only 2 metabolites-pregnenolone sulfate (odds ratio = 0.64, 95% confidence interval = 0.44-0.92) and fucose (odds ratio = 0.69, 95% confidence interval = 0.47-0.97)-were associated with decreased risk. Metabolite set enrichment analysis revealed that higher levels of lysophosphatidylethanolamines (false discovery rate = 0.01) and lysophosphatidylcholines (false discovery rate = 0.01) in presurgical blood were associated with increased risk of persistent postsurgical pelvic pain.

CONCLUSION(S)

Our results suggest that dysregulation of multiple groups of lipid metabolites may play a role in the persistence of pelvic pain postsurgery among young endometriosis patients.

Vertical transmission of methicillin-resistant Staphylococcus aureus at delivery and its clinical impact: An observational, prospective cohort study

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) infection has a significant clinical impact on both pregnant women and neonates. The aim of this study was to assess accurately the vertical transmission rate of MRSA and its clinical impacts on both pregnant mothers and neonates.

MATERIAL AND METHODS

We conducted a prospective observational cohort study of 898 pregnant women who were admitted to our department and 905 neonates from August 2016 to December 2017. MRSA was cultured from nasal and vaginal samples taken from the mothers at enrollment and from nasal and umbilical surface swabs taken from neonates at the time of delivery. We examined the vertical transmission rate of MRSA in mother-neonate pairs. We used multivariable logistic regression to identify risk factors for maternal MRSA colonization and maternal/neonatal adverse outcomes associated with maternal MRSA colonization.

RESULTS

The prevalence of maternal MRSA colonization was 6.1% (55 of 898) at enrollment. The independent risk factors were multiparity and occupation (healthcare provider) (odds ratio [OR] 2.35, 95% confidence interval [CI] 1.25-4.42 and OR 2.58, 95% CI 1.39-4.79, respectively). The prevalence of neonatal MRSA colonization at birth was 12.7% (7 of 55 mother-neonate pairs) in the maternal MRSA-positive group, whereas it was only 0.12% (one of 843 pairs) in the maternal MRSA-negative group (OR 121, 95% CI 14.6-1000). When maternal vaginal samples were MRSA-positive, vertical transmission was observed in four of nine cases (44.4%) in this study. Skin and soft tissue infections developed more frequently in neonates in the maternal MRSA-positive group than in the MRSA-negative group (OR 7.47, 95% CI 2.50-22.3).

CONCLUSIONS

The prevalence of MRSA in pregnant women was approximately 6%. Vertical transmission caused by maternal vaginal MRSA colonization was observed in four of nine cases (44.4%). Although our study includes a limited number of maternal MRSA positive cases, the vertical transmission of MRSA may occur in up to 44% of neonates of mothers with vaginal MRSA colonization. Maternal MRSA colonization may be associated with increased development of skin and soft tissue infections in neonates via vertical transmission.

Common Analgesic Use for Menstrual Pain and Ovarian Cancer Risk

Menstrual pain has been associated with increased ovarian cancer risk, presumably through increased inflammation, which is known to play a critical role in ovarian carcinogenesis. Analgesic medications are frequently used to treat menstrual pain, some of which lower ovarian cancer risk. In this study, we examined the association between analgesic use for menstrual pain during the premenopausal period and ovarian cancer risk among women with history of menstrual pain. We used data from the New England Case-Control Study, including 1,187 epithelial ovarian cancer cases and 1,225 population-based controls enrolled between 1998 and 2008 with detailed information on analgesic use for their menstrual pain. We used unconditional logistic regression to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for the association between analgesic use (i.e., aspirin, ibuprofen, acetaminophen) for menstrual pain and ovarian cancer risk. We further conducted a stratified analysis by intensity of menstrual pain (mild/moderate, severe). Among women with menstrual pain during their 20s and 30s, ever use of analgesics for menstrual pain was not significantly associated with ovarian cancer risk. However, among women with severe menstrual pain, ever use of aspirin or acetaminophen for menstrual pain was inversely associated with risk (OR, 0.41; 95% CI, 0.18-0.94 and OR, 0.43; 95% CI, 0.21-0.88 compared with never users, respectively). No significant association was observed between analgesic use and ovarian cancer risk among women with mild/moderate menstrual pain (P _interaction ≤ 0.03). Our results suggest that use of aspirin or acetaminophen for severe menstrual pain may be associated with lower risk of ovarian cancer. PREVENTION RELEVANCE: This study investigates whether analgesic use specifically for menstrual pain during the premenopausal period influences ovarian cancer risk. Our results suggest use of aspirin or acetaminophen for severe menstrual pain may be associated with lower risk of ovarian cancer among women with severe menstrual pain.

Prospective Analyses of Lifestyle Factors Related to Energy Balance and Ovarian Cancer Risk by Infiltration of Tumor-Associated Macrophages

BACKGROUND

Lifestyle factors related to energy balance have been associated with ovarian cancer risk and influence the tumor immune microenvironment, including tumor-associated macrophages (TAM). However, no studies have assessed whether these factors differentially impact ovarian cancer risk by TAM densities.

METHODS

We conducted a prospective analysis in the Nurses' Health Studies to examine the associations of physical activity, sitting time, and a food-based empirical dietary inflammatory pattern (EDIP) score with invasive epithelial ovarian cancer risk by TAM density assessed by immunohistochemistry. We considered density of CD68 (marker of total TAMs) and CD163 (marker of pro-carcinogenic M2-type TAMs), and their ratios. We used multivariable Cox proportional hazards regression to calculate hazard ratios (HR) and 95% confidence intervals (CI) of exposures with risk of ovarian tumors with high versus low TAMs, including analyses stratified by body mass index.

RESULTS

Analyses included 312 incident ovarian cancer cases with TAM measurements. Physical activity, sitting time, and EDIP score were not differentially associated with ovarian cancer risk by TAM densities (P heterogeneity > 0.05). Among overweight and obese women, higher EDIP score was associated with increased risk of CD163 low-density tumors (HR comparing extreme tertiles, 1.57; 95% CI, 0.88-2.80; P trend = 0.01), but not CD163 high-density tumors (comparable HR, 1.16; 95% CI, 0.73-1.86; P trend = 0.24), though this difference was not statistically significant (P heterogeneity = 0.22).

CONCLUSIONS

We did not observe differential associations between lifestyle factors and ovarian cancer risk by TAM densities.

IMPACT

Future investigations examining the interplay between other ovarian cancer risk factors and the tumor immune microenvironment may help provide insight into ovarian cancer etiology.

Intrauterine device use and risk of ovarian cancer: Results from the New England Case-Control study and Nurses' Health Studies

Results of studies assessing intrauterine device (IUD) use and ovarian cancer risk are inconsistent. We examined the association between IUD use, including duration, type and timing of use, and ovarian cancer risk using three population-based studies. Data from the New England Case-Control Study (NEC) and two prospective cohort studies, the Nurses' Health Studies (NHS/NHSII), were included in the analysis. Information on IUD use was collected by in-person interview in NEC and by biennial questionnaire in NHS/NHSII. We used unconditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI) in NEC and Cox regression to calculate hazard ratios (HR) and 95% CI in NHS/NHSII. We used meta-analysis to combine the NEC and the pooled NHS/NHSII results. Overall, IUD use was not associated with epithelial ovarian cancer risk (OR = 0.96, 95% CI: 0.81-1.14 in NEC; HR = 0.89, 95% CI: 0.69-1.15 in NHS/NHSII; combined RR = 0.94, 95% CI: 0.81-1.08). Among IUD users, older age at first use was associated with increased ovarian cancer risk (P-trend = .03). We did not observe significant associations by IUD type or duration of use. In conclusion, IUD use was not associated with ovarian cancer risk in our study.

IgA transcytosis and antigen recognition govern ovarian cancer immunity

Most ovarian cancers are infiltrated by prognostically relevant activated T cells^1–3, yet exhibit low response rates to immune checkpoint inhibitors⁴. Memory B cell and plasma cell infiltrates have previously been associated with better outcomes in ovarian cancer^5,6, but the nature and functional relevance of these responses are controversial. Here, using 3 independent cohorts that in total comprise 534 patients with high-grade serous ovarian cancer, we show that robust, protective humoral responses are dominated by the production of polyclonal IgA, which binds to polymeric IgA receptors that are universally expressed on ovarian cancer cells. Notably, tumour B-cell-derived IgA redirects myeloid cells against extracellular oncogenic drivers, which causes tumour cell death. In addition, IgA transcytosis through malignant epithelial cells elicits transcriptional changes that antagonize the RAS pathway and sensitize tumour cells to cytolytic killing by T cells, which also contributes to hindering malignant progression. Thus, tumour-antigen-specific and -antigen-independent IgA responses antagonize the growth of ovarian cancer by governing coordinated tumour cell, T cell and B cell responses. These findings provide a platform for identifying targets that are spontaneously recognized by intratumoural B-cell-derived antibodies, and suggest that immunotherapies that augment B cell responses may be more effective than approaches that focus on T cells, particularly for malignancies that are resistant to checkpoint inhibitors.

In patients with high-grade serous ovarian cancer, robust and protective humoral responses are dominated by B-cell-derived polyclonal IgA that binds to polymeric IgA receptors that are universally expressed on ovarian cancer cells.

Epidemiologic and biologic correlates of serum HE4 and CA125 in women from the National Health and Nutritional Survey (NHANES)

OBJECTIVES

In women with ovarian cancer, tumor features largely determine serum HE4 and CA125 levels, but non-tumor factors may also influence levels and be better understood by studying determinants in a well-characterized sample of women without cancer.

METHODS

Serum HE4 and CA125 were measured in 2302 women from the 2001-2002 cohort of the National Heath and Nutritional Survey (NHANES). Publicly-available data on this cohort included demographic/reproductive variables, blood counts, and measurements of C-reactive protein (CRP), total homocysteine (tHcy), cotinine, and creatinine which were examined as predictors of HE4 and CA125 using multivariate models and correlational analyses.

RESULTS

HE4 increased non-linearly by age and current smokers had higher HE4. CA125 was lower in postmenopausal women and non-whites and trended downward with increasing BMI. Current-users of oral contraceptives (OCs) had lower HE4 and CA125; and a downward trend for CA125 was seen with increasing OC use. Pregnant women had higher CA125 and nursing women higher HE4. HE4 and CA125 were positively correlated with neutrophils, monocytes, and the neutrophil-to-lymphocyte ratio and inversely correlated with lymphocytes and the lymphocyte-to-monocyte ratio. CRP was positively correlated with both HE4 and CA125 in postmenopausal women. Strong positive correlations existed for HE4 with both tHcy and creatinine.

CONCLUSIONS

Serum levels of HE4 and CA125 are influenced by several hormonal or environmental stimuli which affect non-cancerous tissues normally expressing HE4 or CA125. Cytokine co-expression in those tissues may, in turn, affect white cell counts and account for their correlation with HE4 or CA125 levels.

Abstract A19: Aspirin use and ovarian cancer risk by lymphocyte infiltration

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 &lt;0.001). We observed similar results for aspirin duration and tablets. For duration, comparing ≥10 years of aspirin use to &lt;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 &lt;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.

Evaluation of CA125 in relation to pain symptoms among adolescents and young adult women with and without surgically-confirmed endometriosis

Endometriosis is a painful gynecologic disease affecting one in ten reproductive aged women worldwide. Few studies have correlated this symptomatology with biomarker levels among women with and without endometriosis, and no studies correlating pain with biomarker levels have been performed in young patient populations. The purpose of this study was to examine whether CA125 correlates with different types and severity of pain among adolescents and young women with and without endometriosis and assess its performance as an endometriosis biomarker among those presenting with dysmenorrhea in this young population. Reproductive-aged women with laparoscopically-confirmed endometriosis (n = 282) and controls (n = 293) who participated in The Women's Health Study: From Adolescence to Adulthood (A2A), a cohort of adolescents and young women enrolled from 2012-2018, were included in this cross-sectional analysis. Plasma CA125 values were measured using WERF EPHect compliant blood samples collected at enrollment. Average CA125 were calculated by self-reported pain type (i.e. dysmenorrhea, non-cyclic/general pelvic pain, dyspareunia), severity, and frequency in endometriosis cases and controls. Median age at blood draw was 24 years in controls and 17 years in cases, with 68% and 89% non-Hispanic white, respectively. Most endometriosis cases (95%) were rASRM stage I/II. Average CA125 values were 12.5 U/mL in controls and 12.1 U/mL in cases adjusted for age. CA125 did not differ by pain type, its severity, or frequency in endometriosis cases or controls. Among participants who reported dysmenorrhea, CA125 did not discriminate endometriosis cases from controls using cutoff of 35 U/mL (AUC = 0.51, 95%CI = 0.50-0.53). Among adolescents and young adult women, CA125 did not correlate with pain type. CA125 did not efficiently discriminate endometriosis cases from controls even when accounting for pain symptomatology. Average CA125 values were low in adolescents and young women in both endometriosis cases and controls, suggesting cautious interpretation may be needed when measuring CA125 in this population.

Abstract 34: Predictors of discordance between image-based and manual scoring of immunohistochemical stains in ovarian cancer tissue microarrays

Digital image-based scoring of immunohistochemistry (IHC) staining allows faster, more objective and potentially more reproducible quantification of area stained or cell counts compared to manual scoring. However, predictors of discrepancies between these two assessment methods are not well understood. We examined clinical and pathological characteristics associated with discordance between image-based and manual scoring using ovarian cancer tissue microarrays (TMA) across a range of IHC stains. We evaluated 2,159 TMA cores from 681 ovarian cancer cases stained by four tissue cytoplasmic stains quantified as percentage of the tumor area stained (POSTN, CXCL14, ADH1B, COL11A1) and two immune cell markers quantified by cell count of infiltrating immune cells (CD68, CD163). The TMA slides were scored manually using semi-quantitative scoring by gynecologic pathologists as well as digitally using image-based Definiens automated platform. We used generalized linear mixed models with individual patients and TMAs included as random effects and stain as fixed effect to examine predictors of discordance, defined as absolute difference of ≥1SD in z-scores between image-based and manual scoring, overall and by each stain. The multi-level model included characteristics of the TMA, core, and tumor factors as predictors. Overall, TMA construction by automated robotic system (vs manual), smaller core size or area, borderline (vs invasive tumors), and having no geographic necrosis in the tumor were significantly associated with greater discordance between image-based and manual scoring. Interestingly, all these factors, except geographic necrosis, were differentially associated with discordance across the stains (p-interaction &lt;0.05). Having multiple loci of geographic necrosis was associated with less discordance (OR=0.84, 95%CI=0.72-0.97). Invasive tumors compared to borderline tumors were less likely to be discordantly scored overall (OR=0.80, 95%CI=0.65-1.00) and for tissue cytoplasmic stains (OR range: 0.42-0.73), with associations in the opposite direction for immune cell markers (OR range: 1.21-2.37). Core areas in the lowest quartile vs all other cores were associated with greater discordance (OR=1.18, 95%CI=1.05-1.32), which was more notable for the tissue cytoplasmic stains (OR range: 1.18-2.00) compared to immune cell markers (OR range: 0.83-0.86). TMAs created by robot vs by hand had 64% higher odds of discordance (95%CI=1.20-2.25), which was more apparent when blank rows and columns were included on the TMA. Overall, TMA, core, and tumor level factors were related to discordance between image-based and manual scoring. Some stain types may be more susceptible to specific pre-analytic factors suggesting that reproducibility studies of manual vs image-based scoring should be conducted on a proportion of cases in large scale projects.

Citation Format: Naoko Sasamoto, Mary Townsend, Farnoosh Abbas-Aghababazadeh, Kathryn L. Terry, Joseph O. Johnson, Jonathan L. Hecht, Brooke L. Fridley, Shelley S. Tworoger. Predictors of discordance between image-based and manual scoring of immunohistochemical stains in ovarian cancer tissue microarrays [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 34.

In utero and early life exposures in relation to endometriosis in adolescents and young adults

OBJECTIVE

Endometriosis is a common gynecologic disorder often associated with severe pelvic pain and infertility with few known modifiable risk factors. We investigated whether in utero and early life exposures are associated with surgically diagnosed endometriosis among adolescents and young adults.

STUDY DESIGN

This case-control study, including 295 laparoscopically-confirmed endometriosis cases and 309 population-based controls aged <25 years, was conducted using data from The Women's Health Study: From Adolescence to Adulthood which enrolled participants from 2012 to 2018. Information on in utero and early life factors were collected using a modified WERF EPHect questionnaire at enrollment, including their mother's age at delivery, birthweight, gestation length, exposure to smoking in utero and secondhand smoke during childhood up to age 13, and if the participant was breastfed.

RESULTS

Median age at enrollment was 17 years (range 12-24) in cases and 22 years (range 7-24) in controls, with 83 % and 68 % non-Hispanic whites, respectively. The majority of cases (95 %) were rASRM stage I or II at diagnostic surgery. Exposure to breastfeeding in early life was associated with lower odds of endometriosis diagnosis (OR = 0.39, 95 % CI = 0.21-0.74). Exposure to secondhand smoke during childhood due to maternal smoking was associated with increased odds of endometriosis diagnosis (OR = 2.70, 95 % CI = 1.11-6.60).

CONCLUSIONS

Among adolescents and young adults, our data suggest exposures to breastfeeding in early life and secondhand smoke during childhood may be associated with endometriosis risk, providing insight into etiologic pathways to be explored in this young population.

Association Between Breastfeeding and Ovarian Cancer Risk

Importance

Breastfeeding has been associated with a reduced risk of epithelial ovarian cancer in multiple studies, but others showed no association. Whether risk reduction extends beyond that provided by pregnancy alone or differs by histotype is unclear. Furthermore, the observed associations between duration and timing of breastfeeding with ovarian cancer risk have been inconsistent.

Objective

To determine the association between breastfeeding (ie, ever/never, duration, timing) and ovarian cancer risk overall and by histotype.

Design, Setting, and Participants

A pooled analysis of parous women with ovarian cancer and controls from 13 case-control studies participating in the Ovarian Cancer Association Consortium was performed. Odds ratios (ORs) and 95% CIs of the overall association were calculated using multivariable logistic regression and polytomous logistic regression for histotype-specific associations. All data were collected from individual sites from November 1989 to December 2009, and analysis took place from September 2017 to July 2019.

Exposures

Data on breastfeeding history, including duration per child breastfed, age at first and last breastfeeding, and years since last breastfeeding were collected by questionnaire or interview and was harmonized across studies.

Main Outcomes and Measures

Diagnosis of epithelial ovarian cancer.

Results

A total of 9973 women with ovarian cancer (mean [SD] age, 57.4 [11.1] years) and 13 843 controls (mean [SD] age, 56.4 [11.7] years) were included. Breastfeeding was associated with a 24% lower risk of invasive ovarian cancer (odds ratio [OR], 0.76; 95% CI, 0.71-0.80). Independent of parity, ever having breastfed was associated with reduction in risk of all invasive ovarian cancers, particularly high-grade serous and endometrioid cancers. For a single breastfeeding episode, mean breastfeeding duration of 1 to 3 months was associated with 18% lower risk (OR, 0.82; 95% CI, 0.76-0.88), and breastfeeding for 12 or more months was associated with a 34% lower risk (OR, 0.66; 95% CI, 0.58-0.75). More recent breastfeeding was associated with a reduction in risk (OR, 0.56; 95% CI, 0.47-0.66 for <10 years) that persisted for decades (OR, 0.83; 95% CI, 0.77-0.90 for ≥30 years; P for trend = .02).

Conclusions and Relevance

Breastfeeding is associated with a significant decrease in risk of ovarian cancer overall and for the high-grade serous subtype, the most lethal type of ovarian cancer. The findings suggest that breastfeeding is a potentially modifiable factor that may lower risk of ovarian cancer independent of pregnancy alone.

Adverse Pregnancy Outcomes in Endometriosis - Myths and Realities

PURPOSE OF REVIEW

There is increasing interest in the long-term health and comorbid conditions associated with endometriosis for both women and neonates. The purpose of this review was to synthesize and discuss the current state of the literature investigating endometriosis and risk of adverse pregnancy outcomes.

RECENT FINDINGS

Methodologic considerations for studying endometriosis and adverse pregnancy outcomes include complexities regarding the comparison population, endometriosis definition, sample size, residual confounding, and interactions. The current research on endometriosis and adverse pregnancy outcomes should be interpreted cautiously. To date, evidence suggests that endometriosis may be associated with higher risk of ectopic pregnancy, placenta previa, preterm birth, and cesarean section. While an association with miscarriage and stillbirth has been consistently observed, the relative risk was small.

SUMMARY

Pregnant women with endometriosis may be at higher risk for certain adverse pregnancy outcomes and may therefore benefit from additional monitoring. However, additional research is needed to confirm these associations and should focus on ensuring studies have internal and external validity, as well as, investigate the potential for differences in endometriosis phenotypes. Moreover, future research should focus on understanding potential mechanisms of association and better understanding how early interventions, through increased monitoring or screening during pregnancy, may improve outcomes.

Development and validation of circulating CA125 prediction models in postmenopausal women

BACKGROUND

Cancer Antigen 125 (CA125) is currently the best available ovarian cancer screening biomarker. However, CA125 has been limited by low sensitivity and specificity in part due to normal variation between individuals. Personal characteristics that influence CA125 could be used to improve its performance as screening biomarker.

METHODS

We developed and validated linear and dichotomous (≥35 U/mL) circulating CA125 prediction models in postmenopausal women without ovarian cancer who participated in one of five large population-based studies: Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO, n = 26,981), European Prospective Investigation into Cancer and Nutrition (EPIC, n = 861), the Nurses' Health Studies (NHS/NHSII, n = 81), and the New England Case Control Study (NEC, n = 923). The prediction models were developed using stepwise regression in PLCO and validated in EPIC, NHS/NHSII and NEC.

RESULT

The linear CA125 prediction model, which included age, race, body mass index (BMI), smoking status and duration, parity, hysterectomy, age at menopause, and duration of hormone therapy (HT), explained 5% of the total variance of CA125. The correlation between measured and predicted CA125 was comparable in PLCO testing dataset (r = 0.18) and external validation datasets (r = 0.14). The dichotomous CA125 prediction model included age, race, BMI, smoking status and duration, hysterectomy, time since menopause, and duration of HT with AUC of 0.64 in PLCO and 0.80 in validation dataset.

CONCLUSIONS

The linear prediction model explained a small portion of the total variability of CA125, suggesting the need to identify novel predictors of CA125. The dichotomous prediction model showed moderate discriminatory performance which validated well in independent dataset. Our dichotomous model could be valuable in identifying healthy women who may have elevated CA125 levels, which may contribute to reducing false positive tests using CA125 as screening biomarker.

Abstract DP-013: DEVELOPMENT AND VALIDATION OF CIRCULATING CA125 PREDICTION MODEL IN POSTMENOPAUSAL WOMEN WITHOUT OVARIAN CANCER

BACKGROUND: Cancer antigen 125 (CA125) is a membrane bound glycosylated mucin which has been reported to be the most promising biomarker for ovarian cancer screening. However, results from two large randomized trials comparing screening with CA125 and transvaginal ultrasound to usual care have shown no clinically significant difference in ovarian cancer mortality. A major limitation of CA125 as an ovarian cancer screening biomarker has been low specificity and variation between individuals by personal characteristics. Identifying personal characteristics that influence CA125 levels could be used to create personalized thresholds for CA125 thereby improving its performance as an ovarian cancer screening biomarker. We developed and conducted internal and external validation of two prediction models (linear and dichotomous) of circulating CA125 among postmenopausal women using 28,842 controls without ovarian cancer in four large population-based studies.

METHODS: We identified controls from three prospective cohort studies, including Prostate, Lung, Colorectal, and Ovarian (PLCO, n=26,981), European Prospective Investigation into Cancer and Nutrition (EPIC, n=861), and the Nurses' Health Studies (NHS, n=164) as well as one population-based case-control study, the New England Case Control Study (NEC, n=1,000). CA125 was measured using the CA125II assay in PLCO, NHS, and NEC. Meso Scale Discovery (MSD) platform was used to measure CA125 in EPIC. The MSD assay values were recalibrated to the CA125II scale based on 534 NEC controls with both measurements. CA125 levels were log-transformed to achieve normal distribution or dichotomized by the upper limit of normal (35 U/ml). The prediction models were developed and internally validated using postmenopausal controls in PLCO, and then were externally validated using postmenopausal controls in EPIC, NHS and NEC. The prediction models were developed using stepwise linear or logistic regression with &lt;0.15 as significance level for entry and retention considering factors which have been previously reported to be associated CA125 in postmenopausal women as candidate predictors (age, race, body-mass index (BMI), smoking status and duration, age at menarche, oral contraceptive use, party, age at menopause, time since menopause, hormone replacement therapy (HRT) use and duration, family history of ovarian or breast cancer, previous history of cancer, previous history of benign ovarian cyst, history of endometriosis). We then evaluated the performance of the model in the independent validation datasets.

RESULTS: The linear CA125 prediction model included age, race, BMI, smoking status and duration, hysterectomy, parity, age at menopause, and duration of HRT use as predictors, explaining 5% of the variability of log-transformed CA125 levels. The correlation coefficient of the measured and predicted log-transformed CA125 was 0.18 in the PLCO testing dataset, and showed comparable correlations across the independent validation datasets (0.14-0.16). The dichotomous CA125 prediction model included age, race, BMI, duration of HRT use, and hysterectomy as predictors with an AUC of 0.63 in the PLCO testing dataset and 0.71 in NEC.

CONCLUSION: We developed linear and dichotomous circulating CA125 prediction models in postmenopausal women that can form the foundation for creating personalized thresholds of CA125. However, other factors should be considered to increase the predictive capacity of the model.

Citation Format: Naoko Sasamoto, Ana Babic, Bernard A. Rosner, Renée T. Fortner, Allison F. Vitonis, Hidemi Yamamoto, Raina N. Fichorova, Daniel W. Cramer, Rudolf Kaaks, Shelley S. Tworoger, Kathryn L. Terry. DEVELOPMENT AND VALIDATION OF CIRCULATING CA125 PREDICTION MODEL IN POSTMENOPAUSAL WOMEN WITHOUT OVARIAN CANCER [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr DP-013.

Endometriosis and Risk of Adverse Pregnancy Outcomes

OBJECTIVE

To investigate the relationship between endometriosis and adverse pregnancy outcomes.

METHODS

Women between ages 25 and 42 years in 1989 (n=116,429) reported detailed information on pregnancies and reproductive health at baseline and every 2 years thereafter in the Nurses' Health Study II, a cohort study. In 2009, they completed a detailed, pregnancy-focused questionnaire. A total of 196,722 pregnancies were reported. Adverse pregnancy outcomes included spontaneous abortion, ectopic pregnancy, stillbirth, gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (preeclampsia or gestational hypertension), preterm birth, and low birth weight. We estimated the relative risks (RRs) and 95% CIs of adverse pregnancy outcomes comparing pregnancies in women with and without a history of laparoscopically confirmed endometriosis using multivariable log-binomial regression, with generalized estimating equations to account for multiple pregnancies per woman.

RESULTS

Endometriosis was associated with a greater risk of pregnancy loss (spontaneous abortion: RR 1.40, 95% CI 1.31-1.49; ectopic pregnancy: RR 1.46, 95% CI 1.19-1.80). Endometriosis was also associated with a greater risk of GDM (RR 1.35, 95% CI 1.11-1.63) and hypertensive disorders of pregnancy (RR 1.30, 95% CI 1.16-1.45).

CONCLUSIONS

We observed an association between laparoscopically confirmed endometriosis and several adverse pregnancy outcomes. Future research should focus on the potential biological pathways underlying these relationships to inform screening or preventive interventions.

Abstract 640: Breastfeeding pattern and ovarian cancer risk: Results from the Ovarian Cancer Association Consortium

Background: Ovarian cancer is the fifth leading cause of cancer deaths in US women with few modifiable risk factors. Breastfeeding has been observed to be associated with reduced risk of ovarian cancer in multiple studies. However, prior studies reporting the association between breastfeeding pattern and ovarian cancer risk by histologic subtypes have reported inconsistent findings, likely due to small sample size and lack of details on breastfeeding patterns. The objective of this study is to evaluate the association between breastfeeding patterns and ovarian cancer risk by histologic subtypes using individual questionnaire data from the Ovarian Cancer Association Consortium (OCAC).

Method: We evaluated breastfeeding patterns in relation to invasive ovarian cancer risk in 9,807 cases and 12, 971 controls from 13 studies in the OCAC. We performed pooled unconditional logistic regression to evaluate the association between breastfeeding and ovarian cancer risk and used multinomial logistic regression to evaluate the association by histologic subtype. We restricted the analysis to parous women and adjusted for study site, age, body mass index, race, education, oral contraceptive use, number of full-term births, family history of ovarian cancer, and birth decade (to account for change in breastfeeding practice over time). We additionally adjusted for age at first and last births simultaneously when examining the association between first and last age at breastfeeding and ovarian cancer risk.

Results: Women who reported ever breastfeeding had a 24% decreased risk of overall invasive ovarian cancer compared to women who never breastfed (OR=0.76, 95%CI: 0.71-0.81) and this association did not differ significantly by histologic subtypes (p-heterogeneity=0.09). Considering only episodes when women breastfed, we observed lower risk of ovarian cancer in women who had longer average duration per episode compared to women who breastfed &lt; 6 months on average per episode (OR=0.85, 95%CI: 0.77-0.93 for 6-12 months; OR=0.77, 95%CI: 0.66-0.89 for &gt; 12 months; p-trend &lt;0.0001). Older age at first and last breastfeeding was significantly associated with lower risk of ovarian cancer compared to women who never breastfed (OR=0.65, 95%CI: 0.58-0.73 for age &gt;30 years at first breastfeeding; OR=0.60, 95%CI: 0.53-0.69 for age &gt;35 years at last breastfeeding). Compared to women who never breastfed, women who last breastfed &lt; 10 years ago had 54% reduction of risk (OR= 0.46, 95%CI: 0.39-0.56) while women who last breastfed ≥ 30 years ago had 19% reduction of risk (OR=0.81, 95%CI: 0.74-0.88).

Conclusion: Breastfeeding regardless of age or duration was associated with reduced risk of ovarian cancer. Our findings support the benefit of breastfeeding as modifiable risk factor for ovarian cancer regardless of histologic subtypes, which has the potential for reducing the incidence this deadly disease.

Citation Format: Naoko Sasamoto, Ana Babic, Susan Jordan, Harvey Risch, Holly Harris, Mary Anne Rossing, Jennifer Doherty, Marc Goodman, Pamela Thompson, Susanne K. Kjær, Allan Jensen, Joellen Schildkraut, Linda Titus, Daniel Cramer, Elisa Bandera, Weiva Sieh, Valerie McGuire, Rebecca Sutphen, Celeste L. Pearce, Anna H. Wu, Malcolm Pike, Penelope Webb, Francesmary Modugno, Kathryn Terry. Breastfeeding pattern and ovarian cancer risk: Results from the Ovarian Cancer Association Consortium [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 640.