Risk-Reducing Bilateral Salpingo-Oophorectomy for BRCA Mutation Carriers and Hormonal Replacement Therapy: If It Should Rain, Better a Drizzle than a Storm

Women carrying a BRCA mutation have an increased risk of developing breast and ovarian cancer. The most effective strategy to reduce this risk is the bilateral salpingo-oophorectomy, with or without additional risk-reducing mastectomy. Risk-reducing bilateral salpingo-oophorectomy (RRBSO) is recommended between age 35 and 40 and between age 40 and 45 years for women carriers of BRCA1 and BRCA2 mutations, respectively. Consequently, most BRCA mutation carriers undergo this procedure prior to a natural menopause and develop an anticipated lack of hormones. This condition has a detrimental impact on various systems, affecting both the quality of life and longevity; in particular, women carrying BRCA1 mutation, who are likely to have surgery earlier as compared to BRCA2. Hormonal replacement therapy (HRT) is the only effective strategy able to significantly compensate the hormonal deprivation and counteract menopausal symptoms, both in spontaneous and surgical menopause. Although recent evidence suggests that HRT does not diminish the protective effect of RRBSO in BRCA mutation carriers, concerns regarding the safety of estrogen and progesterone intake reduce the use in this setting. Furthermore, there is strong data demonstrating that the use of estrogen alone after RRBSO does not increase the risk of breast cancer among women with a BRCA1 mutation. The additional progesterone intake, mandatory for the protection of the endometrium during HRT, warrants further studies. However, when hysterectomy is performed at the time of RRBSO, the indication of progesterone addition decays and consequently its potential effect on breast cancer risk. Similarly, in patients conserving the uterus but undergoing risk-reducing mastectomy, the addition of progesterone should not raise significant concerns for breast cancer risk anymore. Therefore, BRCA mutation carriers require careful counselling about the scenarios following their RRBSO, menopausal symptoms or the fear associated with HRT use.