Abstract
PURPOSE: In the United States, hysterectomies and oophorectomies are frequently performed before menopause for benign conditions. The procedures are associated with reduced breast cancer-specific mortality among White women. The relationship between premenopausal gynecologic surgery and mortality in Black women with breast cancer is unknown. METHODS: This investigation used incident invasive cases of breast cancer from Phases 1 and 2 of the Carolina Breast Cancer Study a population-based study that recruited Black and White women in North Carolina between 1993 and 2001. Premenopausal gynecologic surgery was operationalized in three categories: no surgery; hysterectomy with bilateral oophorectomy; hysterectomy with conservation of ≥ 1 ovary. Mortality was ascertained using the National Death Index, last updated in 2016. Multivariable-adjusted Cox Proportional Hazard Models were used to estimate the effect of premenopausal surgery on breast cancer-specific and all-cause mortality RESULTS: Hysterectomy with bilateral oophorectomy was associated with reduced breast cancer-specific mortality (HR 0.68; 95% CI 0.49, 0.96). White and Black women had a similar reduction in breast cancer-specific mortality. (HR among white: 0.66; 95% CI 0.43, 1.02), (HR among Black: 0.67; 95% CI 0.37, 1.21). CONCLUSIONS: There was a similar reduction in breast cancer-specific mortality following premenopausal, pre-diagnosis hysterectomy with bilateral oophorectomy across both Black and White women.