American Board of Internal Medicine (ABIM) Certification Practice Exam

Which of the following is not used in the treatment of hormone receptor-positive breast cancer?

1. Tamoxifen

2. Ovarian suppression

3. Radiation therapy

4. Fulvestrant

The correct answer is: Radiation therapy

Radiation therapy is primarily used as a localized treatment modality, mainly aimed at controlling local disease and alleviating symptoms in breast cancer patients. While it can be an important part of managing breast cancer in general, particularly after surgical procedures or for palliative care, it does not specifically target the hormonal pathways involved in hormone receptor-positive breast cancer. In contrast, the other options directly relate to hormonal treatment strategies. Tamoxifen and Fulvestrant are both anti-estrogen medications that effectively block estrogen's action in estrogen receptor-positive tumors. Tamoxifen is commonly used in premenopausal and postmenopausal women, while Fulvestrant is utilized primarily in postmenopausal women, especially those with metastatic disease. Ovarian suppression is another approach aimed at reducing estrogen levels in premenopausal women, thus impacting the growth of hormone receptor-positive tumors. Therefore, while radiation therapy plays a significant role in breast cancer management, it does not fit within the category of systemic treatments specifically used for hormone receptor-positive breast cancer, making it the correct choice in this context.