Background: Pelvic inflammatory disease (PID) has been associated with ovarian cancer risk. To clarify the role of Chlamydia trachomatis and other infectious agents in the development of ovarian cancer, we evaluated the association of serologic markers with incident ovarian cancer using a staged approach in two independent populations.

Methods: Studies included: 1) a case-control study in Poland (244 ovarian cancers/556 control subjects) and 2) a prospective nested case-control study in the PLCO Cancer Screening Trial (160 ovarian cancers/159 control subjects). Associations of serologic marker levels with ovarian cancer risk at diagnostic as well as higher thresholds, identified in Poland and independently evaluated in PLCO, were estimated using multivariable adjusted logistic regression.

Results: In the Polish study, antibodies (based on laboratory cut-point) against the chlamydia plasmid-encoded Pgp3 protein (serological gold standard) were associated with increased ovarian cancer risk (adjusted odds ratio [OR] = 1.63, 95% confidence interval [CI] = 1.20 to 2.22); when a positive result was redefined at higher levels, ovarian cancer risk was increased (cut-point 2: OR = 2.00, 95% CI = 1.38 to 2.89; cut-point 3 [max OR]: OR = 2.19, 95% CI = 1.29 to 3.73). In the prospective PLCO study, Pgp3 antibodies were associated with elevated risk at the laboratory cut-point (OR = 1.43, 95% CI = 0.78 to 2.63) and more stringent cut-points (cut-point 2: OR = 2.25, 95% CI = 1.07 to 4.71); cut-point 3: OR = 2.53, 95% CI = 0.63 to 10.08). In both studies, antibodies against other infectious agents measured were not associated with risk.

Conclusions: In two independent populations, antibodies against prior/current C. trachomatis (Pgp3) were associated with a doubling in ovarian cancer risk, whereas markers of other infectious agents were unrelated. These findings lend support for an association between PID and ovarian cancer.

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.

Growing epidemiologic evidence supports chronic inflammation as a mechanism of ovarian carcinogenesis. An association between a circulating marker of inflammation, C-reactive protein (CRP), and ovarian cancer risk has been consistently observed, yet, potential heterogeneity of this association by tumor and patient characteristics has not been adequately explored. In this study, we pooled data from case-control studies nested within six cohorts in the Ovarian Cancer Cohort Consortium (OC3) to examine the association between CRP and epithelial ovarian cancer risk overall, by histologic subtype and by participant characteristics. CRP concentrations were measured from prediagnosis serum or plasma in 1,091 cases and 1,951 controls. Multivariable conditional logistic regression was used to estimate ORs and 95% confidence intervals (CI). When CRP was evaluated using tertiles, no associations with ovarian cancer risk were observed. A 67% increased ovarian cancer risk was found for women with CRP concentrations >10 mg/L compared with <1 mg/L (OR = 1.67; 95% CI = 1.12-2.48). A CRP concentration >10 mg/L was positively associated with risk of mucinous (OR = 9.67; 95% CI = 1.10-84.80) and endometrioid carcinoma (OR = 3.41; 95% CI = 1.07-10.92), and suggestively positive, although not statistically significant, for serous (OR = 1.43; 95% CI = 0.82-2.49) and clear cell carcinoma (OR = 2.05; 95% CI = 0.36-11.57; P-heterogeneity = 0.20). Heterogeneity was observed with oral contraceptive use (P-interaction = 0.03), where the increased risk was present only among ever users (OR = 3.24; 95% CI = 1.62-6.47). This study adds to the existing evidence that CRP plays a role in ovarian carcinogenesis and suggests that inflammation may be particularly implicated in the etiology of endometrioid and mucinous carcinoma. Significance: C-reactive protein is involved in ovarian carcinogenesis, and chronic inflammation may be particularly implicated in the etiology of mucinous and endometrioid carcinomas.

Background

There is a great need for a prospective randomized trial to evaluate the risks and benefits of opportunistic salpingectomy. Recently, genetic and morphologic studies have indicated that epithelial ovarian cancer predominantly develops in the Fallopian tubes. Consequently, there is reason to believe that salpingectomy would reduce the risk of ovarian cancer. Studies on reducing the risk of ovarian cancer have compared indicated salpingectomy with no salpingectomy, while studies on surgical safety as well as ovarian function after opportunistic salpingectomy have been small with a short follow-up. No study has reported menopausal symptoms.

Methods/design

In this national register-based randomized controlled trial, women <55 years old, planned for a hysterectomy for a benign cause, will be randomized to concomitant salpingectomy or no salpingectomy. The follow-up will be conducted according to already established routines within the register using on-line questionnaires. Primary outcomes have been defined for three different time points: short-term complications up to 8 weeks postoperatively (n = 2800), intermediate-term changes in menopausal symptoms measured by the Menopause Rating Scale at baseline and after 1 year (n = 1670), and long-term epithelial ovarian cancer assessed through national registers after 30 years (n = 5052) (or n = 7001 for high-grade serous cancer). In a sub-study of 75 women, ovarian function will be evaluated through change in anti-Müllerian hormone measured before surgery and after 1 year.

Discussion

Hysterectomy for a benign cause is a common surgical procedure and several national societies recommend salpingectomy while performing a benign hysterectomy, despite a lack of scientific evidence for the safety of the procedure. Sweden has unique conditions for clinical trials because of its national quality registers and health registers with excellent quality and near complete coverage. If no additional risks are associated with concomitant salpingectomy, it can be recommended at the time of benign hysterectomy to reduce the risk of epithelial ovarian cancer. If not, the risks and benefits must be balanced. The results of this study will be important for informing women undergoing a benign hysterectomy.

Trial registration

ClinicalTrials.gov, NCT03045965. Registered on 8 February 2017

BACKGROUND: In recent years, the fallopian tubes have been found to play a critical role in the pathogenesis of ovarian cancer. Therefore, bilateral salpingectomy at the time of hysterectomy has been proposed as a preventive procedure, but with scarce scientific evidence to support the efficiency and safety. OBJECTIVE: Our primary objective was to evaluate the risk of surgical complications and menopausal symptoms when performing bilateral salpingectomy in addition to benign hysterectomy. Furthermore, we sought to compare time in surgery, perioperative blood loss/blood transfusion, duration of hospital stay, days to normal activities of daily living, and days out of work for hysterectomy with bilateral salpingectomy compared with hysterectomy only. A secondary objective was to study the uptake of opportunistic salpingectomy in Sweden. STUDY DESIGN: This was a retrospective observational cohort study based on data from the National Quality Register of Gynecological Surgery in Sweden. Women <55 years of age who had a hysterectomy for benign indications with or without bilateral salpingectomy in 1998 through 2016 were included. Possible confounding was adjusted for in multivariable regression models. RESULTS: During the study period, 23,369 women had a hysterectomy for benign indications. The frequency of bilateral salpingectomy at the time of hysterectomy increased mainly from 2013, which is why the period 2013 through mid-2016 was selected for further analysis (n = 6892). There was a low frequency of vaginal hysterectomy with bilateral salpingectomy performed in this period, which is why only abdominal and laparoscopic surgeries were selected for comparative analysis (n = 4906). This study indicates an increased risk of menopausal symptoms (adjusted relative risk, 1.33; 95% confidence interval, 1.04-1.69) 1 year after hysterectomy with bilateral salpingectomy compared with hysterectomy only. Hospital stay was 0.1 days longer in women having salpingectomy (P = .01), and bleeding was slightly reduced in the salpingectomy group (-20 mL, P = .04). Other outcome measures were not significantly associated with salpingectomy, albeit a tendency toward higher risk of minor complications was seen (adjusted relative risk, 1.30; 95% confidence interval, 0.93-1.83). CONCLUSION: Bilateral salpingectomy at the time of hysterectomy was associated with an increased risk of menopausal symptoms 1 year after surgery. Randomized clinical trials reducing the risk of residual and unmeasured confounding and longer follow-up are needed to correctly inform women on the risks and benefits of opportunistic salpingectomy.

Ovarian cancer risk factors differ by histotype; however, within subtype, there is substantial variability in outcomes. We hypothesized that risk factor profiles may influence tumor aggressiveness, defined by time between diagnosis and death, independent of histology. Among 1.3 million women from 21 prospective cohorts, 4,584 invasive epithelial ovarian cancers were identified and classified as highly aggressive (death in <1 year, n = 864), very aggressive (death in 1 to < 3 years, n = 1,390), moderately aggressive (death in 3 to < 5 years, n = 639), and less aggressive (lived 5+ years, n = 1,691). Using competing risks Cox proportional hazards regression, we assessed heterogeneity of associations by tumor aggressiveness for all cases and among serous and endometrioid/clear cell tumors. Associations between parity (p_het = 0.01), family history of ovarian cancer (p_het = 0.02), body mass index (BMI; p_het ≤ 0.04) and smoking (p_het < 0.01) and ovarian cancer risk differed by aggressiveness. A first/single pregnancy, relative to nulliparity, was inversely associated with highly aggressive disease (HR: 0.72; 95% CI [0.58–0.88]), no association was observed for subsequent pregnancies (per pregnancy, 0.97 [0.92–1.02]). In contrast, first and subsequent pregnancies were similarly associated with less aggressive disease (0.87 for both). Family history of ovarian cancer was only associated with risk of less aggressive disease (1.94 [1.47–2.55]). High BMI (≥35 vs. 20 to < 25 kg/m², 1.93 [1.46–2.56] and current smoking (vs. never, 1.30 [1.07–1.57]) were associated with increased risk of highly aggressive disease. Results were similar within histotypes. Ovarian cancer risk factors may be directly associated with subtypes defined by tumor aggressiveness, rather than through differential effects on histology. Studies to assess biological pathways are warranted.

Background: Cancer antigen 125 (CA125) is the most promising ovarian cancer screening biomarker to date. Multiple studies reported CA125 levels vary by personal characteristics, which could inform personalized CA125 thresholds. However, this has not been well described in premenopausal women. Methods: We evaluated predictors of CA125 levels among 815 premenopausal women from the New England Case Control Study (NEC). We developed linear and dichotomous (>= 35 U/mL) CA125 prediction models and externally validated an abridged model restricting to available predictors among 473 premenopausal women in the European Prospective Investigation into Cancer and Nutrition Study (EPIC). Results: The final linear CA125 prediction model included age, race, tubal ligation, endometriosis, menstrual phase at blood draw, and fibroids, which explained 7% of the total variance of CA125. The correlation between observed and predicted CA125 levels based on the abridged model (including age, race, and menstrual phase at blood draw) had similar correlation coefficients in NEC (r = 0.22) and in EPIC (r = 0.22). The dichotomous CA125 prediction model included age, tubal ligation, endometriosis, prior personal cancer diagnosis, family history of ovarian cancer, number of miscarriages, menstrual phase at blood draw, and smoking status with AUC of 0.83. The abridged dichotomous model (including age, number of miscarriages, menstrual phase at blood draw, and smoking status) showed similar AUCs in NEC (0.73) and in EPIC (0.78). Conclusions: We identified a combination of factors associated with CA125 levels in premenopausal women. Impact: Our model could be valuable in identifying healthy women likely to have elevated CA125 and consequently improve its specificity for ovarian cancer screening.

Background: Neoplastic and non-neoplastic events may raise levels of mucins, CA15.3, and CA125, and generate antibodies against them, but their impact on epithelial ovarian cancer (FOC) risk has not been fully defined.

Methods: CA15.3, CA125, and IgC1 antibodies against them were measured in 806 women who developed FAN; and 1,927 matched controls from the European Prospective Investigation of Nutrition and Cancer. Associations between epidemiologic factors and anti-mucin antibodies were evaluated using generalized linear models; EOC risks associated with anti-mucin antibodies, by themselves or in combination with respective antigens, were evaluated using conditional logistic regression.

Results: In controls, lower antibodies against both mucins were associated with current smoking; and, in postmenopausal women, higher levels with longer oral contraceptive use and later-age-at and shorter-interval-since last birth. Lower antiCA15.3 antibodies were associated with higher body mass and, in premenopausal women, more ovulatory cycles. Higher anti-CA15.3 and anti-CA In antibodies were associated with higher risk for mutinous IOC occurring >= 3 years from enrollment. Long-term risk for serous EOC was reduced in women with low CA125 and high anti-CA125 antibodies relative to women with low concentrations of both.

Conclusions: We found general support for the hypothesis that anti-mucin antibody levels correlate with risk factors for EOC Antibodies alone or in combinations with their antigen may predict longer term risk of specific EOC types.

Impact: Anti-CA125 and anti-CA15.3 antibodies alone or in perspective of antigens may be informative in the pathogenesis of EOC subtypes, but less useful for informing risk for all EOC.

Animal and experimental data suggest that anti‐Müllerian hormone (AMH) serves as a marker of ovarian reserve and inhibits the growth of ovarian tumors. However, few epidemiologic studies have examined the association between AMH and ovarian cancer risk. We conducted a nested case‐control study of 302 ovarian cancer cases and 336 matched controls from nine cohorts. Prediagnostic blood samples of premenopausal women were assayed for AMH using a picoAMH enzyme‐linked immunosorbent assay. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using multivariable‐adjusted conditional logistic regression. AMH concentration was not associated with overall ovarian cancer risk. The multivariable‐adjusted OR (95% CI), comparing the highest to the lowest quartile of AMH, was 0.99 (0.59–1.67) (P_trend: 0.91). The association did not differ by age at blood draw or oral contraceptive use (all P_{heterogeneity}: ≥0.26). There also was no evidence for heterogeneity of risk for tumors defined by histologic developmental pathway, stage, and grade, and by age at diagnosis and time between blood draw and diagnosis (all P_{heterogeneity}: ≥0.39). In conclusion, this analysis of mostly late premenopausal women from nine cohorts does not support the hypothesized inverse association between prediagnostic circulating levels of AMH and risk of ovarian cancer.

OBJECTIVE: Chlamydia trachomatis (C. trachomatis) infection has been suggested to promote epithelial ovarian cancer (EOC) development. This study sought to explore the presence of C. trachomatis DNA and chlamydial heat shock protein 60 (chsp60) in ovarian tissue, as well as anti-chlamydial IgG antibodies in plasma, in relation to subtypes of EOC. METHODS: This cross-sectional cohort consisted of 69 women who underwent surgery due to suspected ovarian pathology. Ovarian tissue and corresponding blood samples were collected at the time of diagnosis. In ovarian tumor tissue, p53, p16, Ki67 and chsp60 were analyzed immunohistochemically, and PCR was used to detect C. trachomatis DNA. Plasma C. trachomatis IgG and cHSP60 IgG were analyzed with a commercial MIF-test and ELISA, respectively. RESULTS: Eight out of 69 women had C. trachomatis DNA in their ovarian tissue, all were invasive ovarian cancer cases (16.7% of invasive EOC). The prevalence of the chsp60 protein, C. trachomatis IgG and cHSP60 IgG in HGSC, compared to other ovarian tumors, was 56.0% vs. 37.2% P = .13, 15.4% vs. 9.3% P = .46 and 63.6% vs. 45.5% P = .33 respectively. None of the markers of C. trachomatis infection were associated with p53, p16 or Ki67. CONCLUSIONS: C. trachomatis was detected in invasive ovarian cancer, supporting a possible role in carcinogenesis of EOC. However, there were no statistically significant associations of chsp60 in ovarian tissue, or plasma anti-chlamydial IgG antibodies, with any of the subtypes of ovarian tumors.