Dr. Andrea Decensi of the European Institute of Oncology in Milan, Italy, and colleagues in Norway gave 105 women varying doses of tamoxifen. The drug has been found to reduce the incidence of breast cancer by more than 40 percent in women who are at high risk of developing the disease. Tamoxifen, sold by AstraZeneca Plc under the name Nolvadex, has been used for years to treat breast cancer. Last year, however, it was found to prevent breast cancer in some women when they took it for five years. It works by blocking the estrogen receptor on cells.
Breast cancer is known to be affected by the hormone.
More tests will be needed. One thing doctors will want to see is if the lower dose reduces the risk of uterine cancer. In a second report in the journal, a team at the University of Pittsburgh and the University of California at Los Angeles said women taking tamoxifen to prevent breast cancer suffer only some of the bad side effects. The 11,000 women taking the drug had vaginal discharge, hot flashes and some of the sexual dysfunction that has been reported, but not weight gain and depression. This is very good news.