Influence of Reproductive Factors on Mortality after Epithelial Ovarian Cancer Diagnosis

Abstract

Although many studies have examined the influence of reproductive factors on ovarian cancer risk, few have investigated their effect on ovarian cancer survival. We examined the prognostic influence of reproductive factors on survival after ovarian cancer diagnosis. We conducted a longitudinal analysis of 410 women, ages 20 to 54 years, who participated in the 1980 to 1982 Cancer and Steroid Hormone study as incident ovarian cancer cases. We obtained their vital status by linking Cancer and Steroid Hormone records with Surveillance, Epidemiology, and End Results data. We used the Kaplan-Meier approach to estimate survival probabilities and Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). During a median follow-up of 9.2 years, 212 women died. Of the reproductive factors examined, only age at menarche and number of lifetime ovulatory cycles (LOC) relative to age significantly predicted ovarian cancer survival. Risk for death was higher among women with highest number of LOC compared with those having fewest LOC (HR, 1.67; 95% CI, 1.20-2.33). Women with fewest LOC had the highest 15-year survival (56.7%; 95% CI, 47.8-64.6%), and women with the highest LOC had the poorest (33.3%; 95% CI, 25.3-41.5%). Women whose age at menarche was <12 years had a higher risk of death compared with women whose menses began at > or =14 years (HR, 1.51; 95% CI, 1.02-2.24). We found that high LOC and early age at menarche were associated with decreased survival after ovarian cancer.