Chemoprevention of Breast Cancer

1. The U.S. Food and Drug Administration has approved the drug tamoxifen for breast cancer risk reduction in high-risk women. This is the first time that any drug has been approved for cancer chemoprevention.

2. Several studies in high-risk women have shown that the use of tamoxifen may reduce a woman's risk of breast cancer by 40-50 percent.

3. There is suggestive evidence that the drug raloxifene, which is used in the prevention and treatment of osteoporosis, may also reduce breast cancer risk. However, the evidence for a chemopreventive effect of this drug is less compelling than the evidence for tamoxifen. The FDA has not approved raloxifene for breast cancer chemoprevention. Therefore, unless ongoing research on raloxifene in the STAR (Study of Tamoxifen and Raloxifene) trial indicates otherwise, tamoxifen remains the only agent with FDA approval for reducing the risk of breast cancer.

4. Physicians should discuss breast cancer chemoprevention with all high-risk women unless there is a medical contraindication to its use. The decision to start chemoprevention should rest on two major factors: a woman's actual risks and what those risks mean to her. Women who are considering chemoprevention need to be aware of all of the potential benefits and risks, and to weigh these factors carefully before making a final decision. Women have the right to know all the information necessary to make educated choices in this important area of their personal health.