American Board of Internal Medicine (ABIM) Certification Practice Exam

Which drug is associated with the most significant reduction in breast cancer risk for women with atypical ductal hyperplasia?

1. Letrozole

2. Exemestane

3. Tamoxifen

4. Aromasin

The correct answer is: Exemestane

The drug associated with the most significant reduction in breast cancer risk for women with atypical ductal hyperplasia is Tamoxifen. Tamoxifen is a selective estrogen receptor modulator (SERM) that works by blocking estrogen receptors in breast tissue. This action significantly reduces the risk of developing breast cancer in women with atypical ductal hyperplasia, a condition that is often considered a marker for increased breast cancer risk. In clinical studies, Tamoxifen has been shown to reduce the incidence of breast cancer by approximately 50% in women at high risk, which includes those with atypical hyperplasia. Its effectiveness stems from its ability to inhibit estrogen's stimulatory effects on breast tissue, which is crucial given the relationship between estrogen and the development of certain types of breast cancer. While Letrozole and Exemestane are aromatase inhibitors that also aim to lower estrogen levels, their primary indication and effectiveness are more in the realm of postmenopausal treatment and prevention rather than specifically for women with atypical ductal hyperplasia. Aromasin is another name for Exemestane, further indicating its similarity in action. Thus, Tamoxifen stands out as the drug with the most robust evidence supporting its role in reducing breast cancer risk