Although risk-reducing bilateral salpingo-oophorectomy is highly effective at reducing ovarian cancer incidence, the risk of primary peritoneal cancer is not reduced and studies indicate that the previously reported effect of this procedure on future breast cancer risk in BRCA1 and BRCA2 mutation carriers might have been overestimated because of uncorrected bias.28 This evidence concerns the gene BRCA1 and ovarian carcinoma.