Multi-center prospective analysis of risk-reducing salpingo-oophorectomy to prevent BRCA-associated breast and ovarian cancer

Abstract

1003 Background: Our groups previously reported on the efficacy of risk-reducing salpingo-oophorectomy (RRSO) for the prevention of BRCA-associated breast and ovarian cancer. (Kauff ND, et al. NEJM 2002; Rebbeck TR, et al. NEJM 2002) Limitations of those reports included relatively short prospective follow-up and lack of power to analyze the protection of RRSO when participants were stratified by BRCA1 vs. BRCA2. To address these limitations, we have pooled our updated datasets to provide robust estimates of the efficacy of RRSO. Methods: 886 women ≥ 30 years of age, with a deleterious mutation in BRCA1 or BRCA2 and ovaries in-situ at time of genetic test results, were enrolled on prospective follow-up studies at one of eleven centers from 11/1/1994 - 12/1/2004. Women chose to participate in either ovarian surveillance or undergo RRSO. Follow-up information was collected by questionnaire and medical record review. Follow-up time was counted from time of RRSO or from time of genetic test results for women who did not undergo RRSO. After excluding cancers diagnosed within the first 6 months of follow-up, the effect of RRSO on time to diagnosis of breast or BRCA-associated gynecologic cancer was analyzed using a Cox proportional-hazards model. Results: 559 (63%) participants underwent RRSO a median of 5 months after genetic test results. 12 occult ovarian or fallopian tube cancers were diagnosed at time of RRSO. During a mean 40 months follow-up, RRSO was associated with a 52% reduction in breast cancer risk and a 91% reduction in ovarian cancer risk (see Table ). When the cohort was stratified by mutation status, RRSO was associated with a reduced risk of BRCA1-associated ovarian cancer and BRCA2-associated breast cancer. Conclusions: The results confirm that RRSO is highly protective against BRCA-associated breast and ovarian cancer. These results also generate the hypothesis that the protection conferred by RRSO against specific cancers may differ between carriers of BRCA1 and BRCA2 mutations. [Table: see text] No significant financial relationships to disclose.