Mary K. Townsend

Prospective Analysis of Circulating Biomarkers and Ovarian Cancer Risk in the UK Biobank

Abstract Background: Risk factors have a limited ability to predict individuals at high risk of developing ovarian cancer among average-risk women, highlighting the need for discovery of novel biomarkers. In the UK Biobank, we investigated serum biomarkers commonly measured in clinical laboratory tests and ovarian cancer risk. Methods: We conducted a prospective analysis of 20 serum biomarkers and ovarian cancer risk in 232,037 female UK Biobank participants (including 1,122 incident ovarian cancer cases diagnosed from 2006 to 2020). Multivariable adjusted Cox proportional hazards models were used to examine associations between biomarkers and ovarian cancer risk overall and by histotype. FDR was used to account for multiple testing. Results: Overall, higher levels of insulin-like growth factor (IGF)-1 [RRquartile 4 vs. 1 = 0.73; 95% confidence interval (CI), 0.60–0.87; P-trend = 0.002/FDR = 0.04], HbA1c (RRquartile 4 vs. 1 = 0.74; 95% CI, 0.62–0.89; P-trend = 0.002/FDR = 0.04), and alanine aminotransferase (RRquartile 4 vs. 1 = 0.76; 95% CI, 0.63–0.91; P-trend = 0.002/FDR = 0.04) were significantly associated with lower ovarian cancer risk. When stratified by histotype, higher IGF1 levels were associated with lower risk of serous (RRquartile 4 vs. 1 = 0.73; 95% CI, 0.58–0.91; P-trend = 0.01/FDR = 0.20) and clear cell tumors (RRquartile 4 vs. 1 = 0.18; 95% CI, 0.07–0.49; P-trend = 0.001/FDR = 0.02), and higher HbA1c levels were associated with lower risk of serous tumors (RRquartile 4 vs. 1 = 0.73; 95% CI, 0.59–0.90; P-trend = 0.004/FDR = 0.08). Conclusions: We observed that higher levels of circulating IGF1, HbA1c, and alanine aminotransferase were associated with lower ovarian cancer risk. Impact: These results suggest metabolism of glucose/amino acid and insulin/IGF1 signaling pathway may be contributing to ovarian carcinogenesis. Further research is needed to replicate our findings and elucidate how systemic changes in metabolism impact ovarian carcinogenesis.

Associations between common contraceptive use and circulating inflammatory biomarkers

Abstract Ovarian cancer incidence has declined in recent decades, due in part to oral contraceptive (OC) use and tubal ligation. However, intrauterine device (IUD) use has increasingly replaced OC use. As ovarian cancer is an inflammation-related disease, we examined the association of OC use, IUD use, and tubal ligation with plasma levels of C-reactive protein (CRP), interleukin 6, and soluble tumor necrosis factor α receptor 2 in the Nurses’ Health Study (NHS) and NHSII. After adjusting for reproductive, hormonal, and lifestyle factors and mutual adjustment for other methods of contraception, there were no differences in inflammatory markers between ever and never use of each method. However, CRP levels decreased from an average of 30.4% (95% CI, –53.6 to 4.4) with every 5 years since initial IUD use (P-trend = .03), while CRP increased an average of 9.9% (95% CI, 5.7, 14.3) with every 5 years of use of OC (P-trend < .0001) as well as differences by body mass index and menopausal status. Our results suggest IUD use and tubal ligation are not associated with higher circulating inflammatory markers long term, although long duration of OC use may increase generalized inflammation, which may in part explain why its protective effect wanes over time. This article is part of a Special Collection on Gynecological Cancer.

Lifetime Exposure to Cigarette Smoke, B-Cell Tumor Immune Infiltration, and Immunoglobulin Abundance in Ovarian Tumors

Abstract Background: Cigarette smoke exposure has been linked to systemic immune dysfunction, including for B-cell and immunoglobulin (Ig) production, and poor outcomes in patients with ovarian cancer. No study has evaluated the impact of smoke exposure across the life-course on B-cell infiltration and Ig abundance in ovarian tumors. Methods: We measured markers of B and plasma cells and Ig isotypes using multiplex immunofluorescence on 395 ovarian cancer tumors in the Nurses’ Health Study (NHS)/NHSII. We conducted beta-binomial analyses evaluating odds ratios (OR) and 95% confidence intervals (CI) for positivity of immune markers by cigarette exposure among cases and Cox proportional hazards models to evaluate hazard ratios (HR) and 95% CI for developing tumors with low (<median) or high (≥median) immune cell/Ig percentage. Results: There were no associations between smoke exposure and B-cell or IgM infiltration in ovarian tumors. Among cases, we observed higher odds of IgA+ among ever smokers (OR, 1.54; 95% CI, 1.14–2.07) and ever smokers with no parental smoke exposure (OR, 2.03; 95% CI, 1.18–3.49) versus never smokers. Women with parental cigarette smoke exposure versus not had higher risk of developing ovarian cancer with low IgG+ (HR, 1.51; 95% CI, 1.10–2.09), whereas ever versus never smokers had a lower risk (HR, 0.74; 95% CI, 0.56–0.99). Conclusions: Ever smoking was associated with increased odds of IgA in ovarian tumors. Impact: IgA has been associated with improved ovarian cancer outcomes, suggesting that although smoking is associated with poor outcomes in patients with ovarian cancer, it may lead to improved tumor immunogenicity.

The Association of Kidney Function and Inflammatory Biomarkers with Epithelial Ovarian Cancer Risk

Abstract Background: One of the mechanisms of ovarian tumorigenesis is through inflammation. Kidney dysfunction is associated with increased inflammation; thus, we assessed its relationship with ovarian cancer risk. Methods: In prospectively collected samples, we evaluated the association of kidney function markers and C-reactive protein (CRP) with ovarian cancer risk in the UK Biobank. We used multivariable-adjusted Cox proportional hazards models to evaluate quartiles of serum and urine markers with ovarian cancer risk overall and by histology. We assessed effect modification by CRP (≤3.0, >3.0 mg/L). Results: Among 232,908 women (1,110 ovarian cancer cases diagnosed from 2006–2020), we observed no association between estimated glomerular filtration rate and ovarian cancer risk (Q4 vs. Q1: HR, 1.00; 95% confidence intervals, 0.83–1.22). Potassium was associated with endometrioid (Q4 vs. Q1: 0.33, 0.11–0.98) and clear cell (4.74, 1.39–16.16) tumors. Poor kidney function was associated with a nonsignificant increase in ovarian cancer risk among women with CRP>3.0 mg/L (e.g., uric acid Q4 vs. Q1; 1.23, 0.81–1.86), but not CRP≤3.0 mg/L (0.83, 0.66–1.05). Other associations did not vary across CRP categories. Conclusions: Kidney function was not clearly associated with ovarian cancer risk. Larger studies are needed to evaluate possible histology specific associations. Given the suggestive trend for increased ovarian cancer risk in women with poor kidney function and high CRP, future work is needed, particularly in populations with a high prevalence of inflammatory conditions. Impact: This study provided the first evaluation of markers of kidney function in relation to ovarian cancer risk.

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

Abstract 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.

Estrogen Receptor-β Expression of Ovarian Tumors and Its Association with Ovarian Cancer Risk Factors

Abstract Background: Differential associations between ovarian cancer risk factors and estrogen receptor-α (ERα) ovarian tumor expression have been noted; however, no research has assessed estrogen receptor-β (ERβ) expression. Thus, in exploratory analyses, we assessed the association of several factors with ovarian cancer risk by ERβ tumor status. Methods: We conducted a nested case–control study within the prospective Nurses' Health Study cohorts (NHS/NHSII), with exposures collected through biennial questionnaires. Paraffin-embedded tumor blocks were requested for cases diagnosed from 1976 to 2006 (NHS) and 1989 to 2005 (NHSII) and tissue microarrays were stained for nuclear ERβ (ERβ-nuc) and cytoplasmic ERβ (ERβ-cyto), with any staining considered positive (+). We obtained odds ratios (OR) and 95% confidence intervals (CI) using multivariate polytomous logistic regression. Results: We included 245 cases [43% ERβ-cyto (+) and 71% ERβ-nuc (+)] and 1,050 matched controls. An inverse association was observed between parity and risk of ERβ-nuc (+) (OR, parous vs. nulliparous: 0.46; 95% CI, 0.26–0.81), but not ERβ-nuc (–) tumors (OR, parous vs. nulliparous: 1.51; 95% CI, 0.45–5.04; Pheterogeneity = 0.04). Conversely, parity was inversely associated with ERβ-cyto (–) tumors (OR, parous vs. nulliparous: 0.42; 95% CI, 0.23–0.78), but was not associated with ERβ-cyto (+) tumors (OR, parous vs. nulliparous: 1.08; 95% CI, 0.45–2.63; Pheterogeneity = 0.05). Associations for other exposures, including hormone therapy, did not differ by ERβ-nuc or ERβ-cyto status. Conclusions: Our results suggest that parity may influence ovarian cancer risk, in part, through alterations in ERβ localization within tumor cells. Impact: Alterations in ERβ expression and localization appear to be important for ovarian cancer etiology. Future research should confirm our results and assess potential biologic mechanisms for the observed associations.

The Risk of Ovarian Cancer Increases with an Increase in the Lifetime Number of Ovulatory Cycles: An Analysis from the Ovarian Cancer Cohort Consortium (OC3)

Abstract Repeated exposure to the acute proinflammatory environment that follows ovulation at the ovarian surface and distal fallopian tube over a woman's reproductive years may increase ovarian cancer risk. To address this, analyses included individual-level data from 558,709 naturally menopausal women across 20 prospective cohorts, among whom 3,246 developed invasive epithelial ovarian cancer (2,045 serous, 319 endometrioid, 184 mucinous, 121 clear cell, 577 other/unknown). Cox models were used to estimate multivariable-adjusted HRs between lifetime ovulatory cycles (LOC) and its components and ovarian cancer risk overall and by histotype. Women in the 90th percentile of LOC (>514 cycles) were almost twice as likely to be diagnosed with ovarian cancer than women in the 10th percentile (<294) [HR (95% confidence interval): 1.92 (1.60–2.30)]. Risk increased 14% per 5-year increase in LOC (60 cycles) [(1.10–1.17)]; this association remained after adjustment for LOC components: number of pregnancies and oral contraceptive use [1.08 (1.04–1.12)]. The association varied by histotype, with increased risk of serous [1.13 (1.09–1.17)], endometrioid [1.20 (1.10–1.32)], and clear cell [1.37 (1.18–1.58)], but not mucinous [0.99 (0.88–1.10), P-heterogeneity = 0.01] tumors. Heterogeneity across histotypes was reduced [P-heterogeneity = 0.15] with adjustment for LOC components [1.08 serous, 1.11 endometrioid, 1.26 clear cell, 0.94 mucinous]. Although the 10-year absolute risk of ovarian cancer is small, it roughly doubles as the number of LOC rises from approximately 300 to 500. The consistency and linearity of effects strongly support the hypothesis that each ovulation leads to small increases in the risk of most ovarian cancers, a risk that cumulates through life, suggesting this as an important area for identifying intervention strategies. Significance: Although ovarian cancer is rare, risk of most ovarian cancers doubles as the number of lifetime ovulatory cycles increases from approximately 300 to 500. Thus, identifying an important area for cancer prevention research.

Reproductive and Hormonal Factors and Risk of Ovarian Cancer by Tumor Dominance: Results from the Ovarian Cancer Cohort Consortium (OC3)

Abstract Background: Laterality of epithelial ovarian tumors may reflect the underlying carcinogenic pathways and origins of tumor cells. Methods: We pooled data from 9 prospective studies participating in the Ovarian Cancer Cohort Consortium. Information on measures of tumor size or tumor dominance was extracted from surgical pathology reports or obtained through cancer registries. We defined dominant tumors as those restricted to one ovary or where the dimension of one ovary was at least twice as large as the other, and nondominant tumors as those with similar dimensions across the two ovaries or peritoneal tumors. Competing risks Cox models were used to examine whether associations with reproductive and hormonal risk factors differed by ovarian tumor dominance. Results: Of 1,058 ovarian cancer cases with tumor dominance information, 401 were left-dominant, 363 were right-dominant, and 294 were nondominant. Parity was more strongly inversely associated with risk of dominant than nondominant ovarian cancer (Pheterogeneity = 0.004). Ever use of oral contraceptives (OC) was associated with lower risk of dominant tumors, but was not associated with nondominant tumors (Pheterogeneity = 0.01). Higher body mass index was associated with higher risk of left-dominant tumors, but not significantly associated with risk of right-dominant or nondominant tumors (Pheterogeneity = 0.08). Conclusions: These data suggest that reproductive and hormonal risk factors appear to have a stronger impact on dominant tumors, which may have an ovarian or endometriosis origin. Impact: Examining the associations of ovarian cancer risk factors by tumor dominance may help elucidate the mechanisms through which these factors influence ovarian cancer risk.

Prolactin and Risk of Epithelial Ovarian Cancer

Abstract Background: Prolactin is synthesized in the ovaries and may play a role in ovarian cancer etiology. One prior prospective study observed a suggestive positive association between prolactin levels and risk of ovarian cancer. Methods: We conducted a pooled case–control study of 703 cases and 864 matched controls nested within five prospective cohorts. We used unconditional logistic regression to calculate adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between prolactin and ovarian cancer risk. We examined heterogeneity by menopausal status at blood collection, body mass index (BMI), age, and histotype. Results: Among women with known menopausal status, we observed a positive trend in the association between prolactin and ovarian cancer risk (Ptrend = 0.045; OR, quartile 4 vs. 1 = 1.34; 95% CI = 0.97–1.85), but no significant association was observed for premenopausal or postmenopausal women individually (corresponding OR = 1.38; 95% CI = 0.74–2.58; Ptrend = 0.32 and OR = 1.41; 95% CI = 0.93–2.13; Ptrend = 0.08, respectively; Pheterogeneity = 0.91). In stratified analyses, we observed a positive association between prolactin and risk for women with BMI ≥ 25 kg/m2, but not BMI < 25 kg/m2 (corresponding OR = 2.68; 95% CI = 1.56–4.59; Ptrend < 0.01 and OR = 0.90; 95% CI = 0.58–1.40; Ptrend = 0.98, respectively; Pheterogeneity < 0.01). Associations did not vary by age, postmenopausal hormone therapy use, histotype, or time between blood draw and diagnosis. Conclusions: We found a trend between higher prolactin levels and increased ovarian cancer risk, especially among women with a BMI ≥ 25 kg/m2. Impact: This work supports a previous study linking higher prolactin with ovarian carcinogenesis in a high adiposity setting. Future work is needed to understand the mechanism underlying this association.

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

Abstract 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 (Pheterogeneity > 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; Ptrend = 0.01), but not CD163 high-density tumors (comparable HR, 1.16; 95% CI, 0.73–1.86; Ptrend = 0.24), though this difference was not statistically significant (Pheterogeneity = 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.

Circulating Biomarkers of Inflammation and Ovarian Cancer Risk in the Nurses' Health Studies

AbstractBackground:Chronic inflammation is a well-established mechanism of ovarian carcinogenesis; however, the specific immunogenic processes influencing ovarian tumor development remain unclear. In a case–control study nested within the Nurses' Health Study (NHS) and the NHSII, we examined the association between six inflammatory chemokines and cytokines [B-cell activating factor (BAFF), C-X-C motif chemokine ligand 13 (CXCL13), IL8, soluble(s)IL2-receptor-α(Rα), sIL6Rα] and epithelial ovarian cancer risk.Methods:Among 299 epithelial ovarian cancer cases and 334 matched controls, six inflammatory biomarkers were measured in plasma collected 1–24 years before diagnosis or index date using two custom multiplex Luminex panels. ORs and 95% confidence intervals (CI) were estimated for the association between each biomarker and risk using multivariable conditional logistic regression with adjustment for relevant confounders. We additionally assessed heterogeneity in the risk associations by histotype [high-grade serous carcinoma (HGSC) vs. non-HGSC], body mass index, smoking status, menopausal status, and aspirin use.Results:Women with the highest versus lowest quartile (Q) levels of CXCL13 had a 72% increased ovarian cancer risk (OR = 1.72; 95% CI = 1.04–2.83; Ptrend = 0.007). The positive association with CXCL13 was stronger in magnitude for non-HGSC, overweight or obese women, and postmenopausal women, although only menopausal status demonstrated statistically significant heterogeneity (Pinteraction = 0.04). The remaining biomarkers were not associated with risk.Conclusions:This first evidence that prediagnostic CXCL13, a B-cell chemoattractant, is associated with an increased risk of epithelial ovarian cancer expands current understanding of the role of inflammation in ovarian carcinogenesis.Impact:CXCL13 may represent a novel biomarker for ovarian cancer.

Modification of the Association Between Frequent Aspirin Use and Ovarian Cancer Risk: A Meta-Analysis Using Individual-Level Data From Two Ovarian Cancer Consortia

PURPOSE Frequent aspirin use has been associated with reduced ovarian cancer risk, but no study has comprehensively assessed for effect modification. We leveraged harmonized, individual-level data from 17 studies to examine the association between frequent aspirin use and ovarian cancer risk, overall and across subgroups of women with other ovarian cancer risk factors. METHODS Nine cohort studies from the Ovarian Cancer Cohort Consortium (n = 2,600 cases) and eight case-control studies from the Ovarian Cancer Association Consortium (n = 5,726 cases) were included. We used Cox regression and logistic regression to assess study-specific associations between frequent aspirin use (≥ 6 days/week) and ovarian cancer risk and combined study-specific estimates using random-effects meta-analysis. We conducted analyses within subgroups defined by individual ovarian cancer risk factors (endometriosis, obesity, family history of breast/ovarian cancer, nulliparity, oral contraceptive use, and tubal ligation) and by number of risk factors (0, 1, and ≥ 2). RESULTS Overall, frequent aspirin use was associated with a 13% reduction in ovarian cancer risk (95% CI, 6 to 20), with no significant heterogeneity by study design ( P = .48) or histotype ( P = .60). Although no association was observed among women with endometriosis, consistent risk reductions were observed among all other subgroups defined by ovarian cancer risk factors (relative risks ranging from 0.79 to 0.93, all P-heterogeneity > .05), including women with ≥ 2 risk factors (relative risk, 0.81; 95% CI, 0.73 to 0.90). CONCLUSION This study, the largest to-date on aspirin use and ovarian cancer, provides evidence that frequent aspirin use is associated with lower ovarian cancer risk regardless of the presence of most other ovarian cancer risk factors. Risk reductions were also observed among women with multiple risk factors, providing proof of principle that chemoprevention programs with frequent aspirin use could target higher-risk subgroups.

Cohort Profile: The Ovarian Cancer Cohort Consortium (OC3)

Associations between Parity, History of Breastfeeding, and T-cell Profile of Ovarian Tumors

Abstract Background: Parity and breastfeeding are associated with systemic changes in maternal inflammation and reduced risk of ovarian cancer, but little is known about their impact on the ovarian tumor immune microenvironment. Methods: We evaluated the associations of self-reported parity and history of breastfeeding with tumor-infiltrating T cells among 1,706 ovarian carcinoma cases with tumor tissue collected across four studies. The abundance of tumor-infiltrating T cells was measured by multiplex immunofluorescence in tumor tissue microarrays. ORs and 95% confidence intervals (CI) for the positivity of tumor immune cells were calculated using beta-binomial models and stratified by histotype. Results: Compared with ovarian tumors in nulliparous women, there was no association between parity and ovarian tumor T-cell abundance among all histotypes combined but suggestion of increased cytotoxic T cells and T-cell exhaustion among parous women with clear-cell tumors. When restricted to parous women, history of breastfeeding was associated with increased odds for all T-cell types [i.e., total T, cytotoxic T, helper T (Th), regulatory T, and exhausted T cells], with ORs ranging from 1.11 to 1.42. For every 6 months of breastfeeding, we observed increased odds of activated Th-cell infiltration (CD3+CD4+CD69+; OR, 1.13, 95% CI, 0.99–1.29), with a similar association for high-grade serous tumors, but lower odds in clear-cell tumors (OR, 0.43, 95% CI, 0.21–0.87). Conclusions: History of breastfeeding may alter the ovarian tumor immune microenvironment by modulating the abundance of tumor-infiltrating T cells. Impact: Although replication is required, history of breastfeeding may play a role in the activation of the ovarian tumor immune response.

Timing of depression in relation to risk of ovarian cancer

Abstract Background Several studies have suggested that depression may be associated with increased risk of ovarian cancer. Less is known about whether timing matters regarding when depression occurs. To provide evidence for an etiologically relevant exposure period, we examined depression occurring during the time in which precursor lesions develop and progress to invasive carcinoma with the risk of developing ovarian cancer. Methods Using data from 2 prospective cohorts (1992-2015), we divided follow-up into consecutive 2-year periods for analytic purposes, referred to as “cancer ascertainment periods.” We estimated associations of depression in the 10 years before each cancer ascertainment period with incident cancer, using Cox proportional hazards models. Next, we estimated associations of depression occurring up to 18 years before each ascertainment period, in 2-year increments, with incident cancer. We adjusted for demographic, health, and behavioral factors. All tests of statistical significance were two-sided, with a P-value threshold of less than .05. Results Depression occurring in the 10 prior years was associated with 30% greater risk of cancer (hazard ratio [HR] = 1.30, 95% confidence interval = 1.15 to 1.46). Associations were similar in fully adjusted models (HR = 1.27). Depression occurring in the 14 years before ascertainment was associated with elevated risk, although only estimates for depression 0-2, 6-8, and 8-10 years before ascertainment reached statistical significance (HR range = 1.20-1.36). Conclusion Depression occurring up to 14 years before cancer ascertainment was associated with greater cancer risk. This is the time of precursor progression to invasive ovarian carcinoma, suggesting depression may be an ovarian cancer-promoting agent.