Sabina Rinaldi

Use of menopausal hormone therapy and ovarian cancer risk in a French cohort study

Abstract Background Epidemiological studies have found that menopausal hormone therapy (MHT) use is associated with an increased ovarian cancer risk. However, whether different MHT types confer the same level of risk is unclear. We estimated the associations between different MHT types and the risk of ovarian cancer in a prospective cohort. Methods The study population included 75 606 postmenopausal women from the E3N cohort. Exposure to MHT was identified from self-reports in biennial questionnaires between 1992 and 2004 and from drug claim data matched to the cohort between 2004 and 2014. Hazard ratios and 95% confidence intervals (CIs) of ovarian cancer were estimated using multivariable Cox proportional hazards models with MHT as a time-varying exposure. Tests of statistical significance were 2-sided. Results Over an average 15.3 years follow-up, 416 ovarian cancers were diagnosed. Hazard ratios of ovarian cancer associated with ever use of estrogens combined with progesterone or dydrogesterone and ever use of estrogens combined with other progestagen were equal to 1.28 (95% CI = 1.04 to 1.57) and 0.81 (95% CI = 0.65 to 1.00), respectively (Phomogeneity = .003), compared with never use. The hazard ratio for unopposed estrogen use was 1.09 (95% CI = 0.82 to 1.46). We found no trend according to duration of use or time since last use except for estrogens combined with progesterone or dydrogesterone, which showed decreasing risk with increasing time since last use. Conclusion Different MHT types may impact ovarian cancer risk differentially. The possibility that MHT containing progestagens other than progesterone or dydrogesterone may confer some protection should be evaluated in other epidemiological studies.

Thyroid hormones and epithelial ovarian cancer risk and survival: results from the European Prospective Investigation into Cancer and Nutrition study

Abstract Background Thyroid-stimulating hormone (TSH) and thyroid hormones (free triiodothyronine [fT3] and free thyroxine [fT4]) may influence cancer outcomes, but evidence for ovarian cancer is limited. Methods We conducted a nested case–control study comparing 578 epithelial ovarian cancer (EOC) cases with matched controls within the European Prospective Investigation into Cancer and Nutrition (EPIC). To examine associations between circulating TSH, fT3, and fT4 levels and EOC risk, we estimated risk ratios (RRs) and 95% confidence intervals (CIs) per SD using conditional logistic regression. Among cases, we evaluated all-cause and EOC-specific survival by prediagnostic hormone levels. Hazard ratios (HRs) and 95% confidence intervals were calculated using multivariable Cox regression. We also estimated covariate-adjusted restricted mean survival time (RMST) and survival probabilities at 5 and 10 years. Results Thyroid hormones were not associated with EOC risk (RR [95% CI] per SD increase: TSH = 0.99 [0.87 to 1.12], fT3 = 1.12 [0.70 to 1.79], and fT4 = 1.08 [0.56 to 2.07]) levels. However, higher TSH levels were associated with better survival (HR [95% CI] per SD: all-cause death = 0.90 [0.82 to 0.99], EOC-specific = 0.88 [0.79 to 0.97]), whereas higher fT4 levels were associated with worse survival (all-cause = 1.10 [1.00 to 1.22], EOC-specific = 1.17 [1.05 to 1.30]), but no association for fT3. RMST and survival probabilities showed similar patterns: for TSH, 10-year RMST and survival increased from 5.3 years and 42.2% in Quartile 1 (Q1) to 6.4 years and 50.7% in Q4. Conversely, for fT4, 10-year RMST declined from 5.6 years (Q1) to 5.1 years Q4, and survival from 46.3% to 37.8%. Conclusion TSH and thyroid hormones might not affect ovarian cancer risk. However, high fT4 and low TSH concentrations may be associated with poorer survival. Further evaluation is suggested in other populations.