Role of SERMs in chemoprevention for high-risk individuals.

• A. SERMs prevent all cancers
• B. SERMs such as tamoxifen reduce breast cancer risk in high-risk women; counseling includes benefits and side effects
• C. SERMs are used only in men
• D. SERMs increase cancer risk

Answer: (B)

SERMs work by blocking estrogen signals in breast tissue, which lowers the chance of developing estrogen receptor–positive breast cancer in women who are at high risk. In practice, drugs like tamoxifen have been shown to meaningfully reduce breast cancer risk in these women, making them a valid chemopreventive option. Because the benefit comes with potential harms, counseling is essential and should cover both the degree of risk reduction and possible side effects. Common concerns include hot flashes and an increased risk of blood clots, and tamoxifen specifically carries an added concern for endometrial cancer. Other SERMs, such as raloxifene, can reduce breast cancer risk as well but have a different side-effect profile (notably a lower endometrial cancer risk but still an increased risk of clots). The role of SERMs is not to prevent all cancers, they are not limited to men, and they do not increase overall cancer risk; their purpose is targeted risk reduction for breast cancer in appropriately selected high-risk individuals with informed decision-making about benefits and risks.