The drug tamoxifen, a proven fighter against breast cancer, may be joined by an equally strong partner in preventing the disease. A nationwide study is under way to determine if the drug raloxifene also is effective in preventing breast cancer, the second-leading cause of cancer death in American women. It will likely change the way we will practice prevention of breast cancer in the next five or 10 years, and stands the chance to make a huge difference. Tamoxifen is a drug that blocks the effects of the hormone estrogen, which is produced by a woman's ovaries and can promote the growth of some cancers. Blocking or lowering the levels of estrogen in a woman is one way of treating breast cancer.
Breast cancer arises over many years.
We know that it is, initially at least, a slow-growing disease. Women taking raloxifene in osteoporosis studies have seen a reduction in the incidence of breast cancer. Sponsored by the National Surgical Adjuvant Breast and Bowel Project, the STAR trial will involve 22,000 postmenopausal women randomly assigned to take either tamoxifen or raloxifene daily for five years. Women will receive regular physical exams, mammograms and gynecological exams throughout the trial. Researchers are excited about the prospect of adding a new weapon to the arsenal of drugs for preventing and treating breast cancer.