Breast Cancer Chemoprevention: A Practical Guide for the Primary Care Provider

Abstract

Several organizations, including the American Society of Clinical Oncology, the National Comprehensive Cancer Network, and the United States Preventive Services Task Force, recommend incorporation of breast cancer risk-based counseling and chemoprevention into routine well-woman care. However, primary care providers report both discomfort with and a lack of medical knowledge on this topic. In this review we present a practical, evidence-based guide for incorporating breast cancer risk assessment and chemoprevention into routine care. We advocate a stepwise approach consisting of: (1) risk assessment and communication, (2) selection of appropriate chemoprevention based on risk-benefit analysis, (3) shared decision-making regarding chemoprevention, and (4) management of chemoprevention side effects. We encourage providers to identify high-risk women and refer them to genetic counseling or a high-risk breast cancer clinic. For women who are not considered high risk, we suggest using the Gail model to estimate a woman's 5-year risk of invasive breast cancer. Usually, the benefits of chemoprevention outweigh the risks of chemoprevention once a woman's 5-year risk of invasive breast cancer reaches 3%. For these women there are several factors that need to be considered when selecting a chemoprevention agent, including patient preference, thrombotic history, menopausal status, absence or presence of a uterus, and bone mineral density. We advocate an evidence-based shared decision-making approach that reflects the woman's individual preferences when communicating risk and counseling about chemoprevention. After starting a chemoprevention agent, close follow-up is important as side effects of chemoprevention are common, including vasomotor symptoms and arthralgias. We also review evidence-based management of chemoprevention side effects.