The American Society of Clinical Oncology (ACOG) has updated their practice guidelines regarding pharmacologic intervention for breast cancer risk reduction. Some of the highlights are are listed below:
- Tamoxifen use for 5 years reduces risk for at least 10 years in premenopausal women, particularly estrogen receptor (ER) – positive invasive tumors.
- Women 50 years or younger have few adverse effects with tamoxifen.
- Vascular/vasomotor adverse effects do not persist post treatment.
- Tamoxifen and raloxifene are equally effective in reducing risk of ER-positive breast cancer in postmenopausal women.
- Raloxifene is associated with lower rates of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen.
- Evidence does not exist regarding whether either agent decreases mortality from breast cancer.
- Recommendations
- For women with increased risk for breast cancer, offer tamoxifen (20 mg/d for 5 y) to reduce risk of invasive ER-positive breast cancer.
- In postmenopausal women, raloxifene (60 mg/d for 5 y) may also be considered.
- Aromatase inhibitors (eg, anastrozole, exemestane, letrozole), fenretinide, or other SERMs are not recommended outside of a clinical trial.