Tubal ligation and survival of ovarian cancer patients

Parity is associated with better prognosis in ovarian germ cell tumors, but not in other ovarian cancer subtypes

Ovarian cancer is influenced by reproductive factors, with a reduced risk of epithelial ovarian cancer in parous women. Nonepithelial ovarian cancer frequently affects young women and often precedes or occurs during the childbearing years. However, the impact of reproductive factors on ovarian cancer survival remains unclear: in epithelial ovarian cancer, data are conflicting, and subtype-specific associations have not been examined, and in nonepithelial ovarian cancer, it has not been studied. Using Swedish registers, we evaluated associations between women's reproductive history and cancer-specific mortality by subtype of epithelial and nonepithelial ovarian cancer in 3791 women born 1953 and later, diagnosed from 1990 to 2018. Hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated using Cox-proportional hazard models. Parity was associated with a 78% decreased risk of cause-specific mortality in 243 women with germ cell tumors (GCTs) (parous vs nulliparous, adjusted for age at diagnosis: HR: 0.22 [95% CI 0.07-0.62]), with a decreased risk with increasing number of births (per birth: HR: 0.60 [95% CI 0.38-0.95]). We found no evidence of associations between parity and cause-specific mortality among the 334 patients with sex-cord stromal tumors, nor among the 3214 patients with epithelial ovarian cancer; neither overall, nor by subtype. In conclusion, in our large, population-based study, parity was associated with a clearly better prognosis in GCTs but not in the other ovarian cancer subtypes. Future research on how hormone exposure impacts GCT development may lead to a better understanding of mechanisms affecting survival.

Menopausal hormone therapy prior to the diagnosis of ovarian cancer is associated with improved survival

PURPOSE

Prior studies of menopausal hormone therapy (MHT) and ovarian cancer survival have been limited by lack of hormone regimen detail and insufficient sample sizes. To address these limitations, a comprehensive analysis of 6419 post-menopausal women with pathologically confirmed ovarian carcinoma was conducted to examine the association between MHT use prior to diagnosis and survival.

METHODS

Data from 15 studies in the Ovarian Cancer Association Consortium were included. MHT use was examined by type (estrogen-only (ET) or estrogen+progestin (EPT)), duration, and recency of use relative to diagnosis. Cox proportional hazards models were used to estimate the association between hormone therapy use and survival. Logistic regression and mediation analysis was used to explore the relationship between MHT use and residual disease following debulking surgery.

RESULTS

Use of ET or EPT for at least five years prior to diagnosis was associated with better ovarian cancer survival (hazard ratio, 0.80; 95% CI, 0.74 to 0.87). Among women with advanced stage, high-grade serous carcinoma, those who used MHT were less likely to have any macroscopic residual disease at the time of primary debulking surgery (p for trend <0.01 for duration of MHT use). Residual disease mediated some (17%) of the relationship between MHT and survival.

CONCLUSIONS

Pre-diagnosis MHT use for 5+ years was a favorable prognostic factor for women with ovarian cancer. This large study is consistent with prior smaller studies, and further work is needed to understand the underlying mechanism.

Reproductive and hormonal factors in relation to survival and platinum resistance among ovarian cancer cases

Background:

Ovarian cancer survival is poor, particularly for platinum-resistant cases. The previous literature on pre-diagnostic reproductive factors and ovarian cancer survival has been mixed. Therefore, we evaluated pre-diagnostic reproductive and hormonal factors with overall survival and, additionally, platinum-chemotherapy resistance.

Methods:

We followed 1649 invasive epithelial ovarian cancer cases who were enrolled between 1992 and 2008 for overall mortality within the New England Case-Control Study and abstracted chemotherapy data on a subset (n=449). We assessed pre-diagnostic reproductive and hormonal factors during in-person interviews. We calculated hazard ratios (HRs) using Cox-proportional hazards models.

Results:

We observed 911 all-cause deaths among 1649 ovarian cancer cases. Self-reported endometriosis and longer duration of hormone therapy use were associated with improved survival (HR: 0.72; 95% confidence interval (CI): 0.54–0.94 and HR, ⩾5 years vs never: 0.70; 95% CI: 0.55–0.90, respectively). Older age at menopause and menarche were associated with worse survival (HR, ⩽50 vs >50 years: 1.23; 95% CI: 1.03–1.46 and HR, 13 vs <13 years: 1.24; 95% CI: 1.06–1.44, respectively). We observed no association between oral contraceptive use, parity and tubal ligation, and overall survival. No significant associations were observed for any of the reproductive and hormonal factors and platinum resistance.

Conclusions:

These results suggest that pre-diagnostic exposures such as endometriosis and HT use may influence overall survival among ovarian cancer patients.

Reproductive factors and epithelial ovarian cancer survival in the EPIC cohort study

BACKGROUND

Reproductive factors influence the risk of developing epithelial ovarian cancer (EOC), but little is known about their association with survival. We tested whether prediagnostic reproductive factors influenced EOC-specific survival among 1025 invasive EOC cases identified in the European Prospective Investigation into Cancer and Nutrition (EPIC) study, which included 521,330 total participants (approximately 370,000 women) aged 25-70 years at recruitment from 1992 to 2000.

METHODS

Information on reproductive characteristics was collected at recruitment. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), and multivariable models were adjusted for age and year of diagnosis, body mass index, tumour stage, smoking status and stratified by study centre.

RESULTS

After a mean follow-up of 3.6 years (±3.2 s.d.) following EOC diagnosis, 511 (49.9%) of the 1025 women died from EOC. We observed a suggestive survival advantage in menopausal hormone therapy (MHT) users (ever vs never use, HR=0.80, 95% CI=0.62-1.03) and a significant survival benefit in long-term MHT users (⩾5 years use vs never use, HR=0.70, 95% CI=0.50-0.99, P(trend)=0.04). We observed similar results for MHT use when restricting to serous cases. Other reproductive factors, including parity, breastfeeding, oral contraceptive use and age at menarche or menopause, were not associated with EOC-specific mortality risk.

CONCLUSIONS

Further studies are warranted to investigate the possible improvement in EOC survival in MHT users.

Hormonal and reproductive risk factors for epithelial ovarian cancer by tumor aggressiveness

BACKGROUND

Approximately half of epithelial ovarian cancers are fatal within 3 years; however, roughly 35% of women survive for at least 10 years. In the Nurses' Health Study, New England Case-Control Study, Australian Ovarian Cancer Study, and NIH-AARP Diet and Health Study, we investigated potential differences in the associations with ovarian cancer risk factors by tumor aggressiveness, defined on the basis of time from diagnosis until death.

METHODS

We calculated relative risks (RR) and 95% confidence intervals (CI) for associations of known or suspected ovarian cancer risk factors with rapidly fatal (death within 3 years of diagnosis) and less aggressive tumors (all others) using Cox proportional hazards competing risks analysis (NHS and AARP) or polytomous logistic regression (NECC, AOCS). Results were combined using random effects meta-analysis.

RESULTS

Increasing age was associated with greater risk of rapidly fatal versus less aggressive disease (RR, 5-year increase: 1.39; 95% CI, 1.29-1.49 vs. RR, 1.09; 95% CI, 1.03-1.16, respectively; Pdiff < 0.0001). Oral contraceptive use was associated with a greater decreased risk of rapidly fatal (RR, 5-year increase: 0.69; 95% CI, 0.58-0.82) versus less aggressive disease (RR, 0.81; 95% CI, 0.74-0.89; Pdiff, 0.002). Conversely, increasing parity was associated only with less aggressive disease (RR per child, 0.87; 95% CI, 0.81-0.93).

CONCLUSION

In this analysis of 4,342 cases, there were clear differences in risk factors for rapidly fatal versus less aggressive ovarian tumors.

IMPACT

Differences in risk factor associations by tumor aggressiveness suggests the developmental pathways through which the tumors develop and may be important for developing primary preventive strategies for the most aggressive cancers.