Cancer Drug Trials Announced

Scientists are seeking 22,000 post-menopausal women at high risk of developing breast cancer for a study comparing the potential of two drugs to prevent the disease.

Researchers announced Tuesday the enrollment of women at 400 medical centers in the United States and Canada for the long-awaited study comparing the drugs Tamoxifen and Raloxifene.

Tamoxifen has long been considered a potent breast cancer treatment. Last year, the Food and Drug Administration approved Tamoxifen as a way to reduce the odds that women at particularly high risk of breast cancer will get the disease.

But Tamoxifen causes serious side effects: It doubled women's risk of uterine cancer, tripled the risk of potentially fatal blood clots and increased chances of developing cataracts.

Raloxifene treats bone-thinning osteoporosis, but studies suggest it could have a similar breast cancer-protecting effect. It, too, has side effects, but doesn't appear to increase the risk of uterine cancer.

The new study, by a research group called the National Surgical Adjuvant Breast and Bowel Project and supported by the National Cancer Institute, will attempt to determine which drug is best.

To find a U.S. study site, call 1-800-4-CANCER; in Canada, call 1-888-939-3333. Or check the National Surgical Adjuvant Breast and Bowel Project or the National Cancer Institute's Cancer Trials Information on the Internet.