Use of exogenous hormones in those at increased risk for breast cancer: contraceptive and menopausal hormones in gene carriers and other high-risk patients

Importance and ObjectiveAddressing the hormonal needs of individuals at increased risk of breast cancer (BC) can be a challenge. Observational, prospective, and case-control data support the safety of hormonal contraception in women, often with the added benefits of ovarian and endometrial cancer risk reduction. The majority of data on menopausal hormone therapy (HT) in the highest-risk patients comes from studies of patients with pathogenic variants in BRCA1 and BRCA2 who undergo early surgical menopause. The benefits of risk-reducing salpingo-oophorectomy are not minimized by HT, whereas its use mitigates accelerated osteoporosis and cardiovascular disease. In other patients at increased risk, such as with family history, studies have shown little risk with significant benefit.MethodsWe review evidence to help women's health practitioners aid patients in making choices. The paper is divided into four parts: 1, contraception in the very high-risk patient (ie, with a highly penetrant BC predisposition gene); 2, contraception in other patients at increased risk; 3, menopausal HT in the gene carrier; and 4, HT in other high-risk patients.Discussion and ConclusionWomen at increased risk for BC both early and later in life should be offered reassurance around the use of premenopausal and postmenopausal hormone therapies. The absolute risks associated with these therapies are low, even in the very high-risk patient, and the benefits are often substantial. Shared decision making is key in presenting options, and knowledge of the data in this area is fundamental to these discussions.