STAR builds upon the success of the Breast Cancer Prevention Trial (BCPT), which showed that high-risk women taking the drug tamoxifen (Nolvadex®) for an average of four years reduced their chance of developing breast cancer by 49 percent. The new study will determine whether raloxifene (Evista®), a drug similar to tamoxifen, is also effective in reducing the chance of developing breast cancer in women who have not had the disease, and whether the drug has benefits over tamoxifen, such as fewer side effects. Raloxifene was recently approved by the FDA as an osteoporosis prevention drug for postmenopausal women.

Tamoxifen, a drug used for 20 years to treat breast cancer, was the focus of the BCPT, a study of over 13,000 women at high risk of breast cancer and the first large-scale breast cancer prevention study in North America. In April 1998, BCPT researchers released the initial study results about 14 months earlier than expected due to the large benefit from tamoxifen.

In addition to reducing breast cancer incidence by almost half, tamoxifen reduced the number of bone fractures of the hip, wrist, and spine. The drug did increase the women's chances of three rare, but life-threatening health problems, endometrial cancer (cancer of the lining of the uterus), deep vein thrombosis (blood clots in a large vein), and pulmonary embolism (blood clot in the lung). Women under age 50 appeared to suffer no excess risk of serious effects from tamoxifen.

Women participating in STAR must be age 35 or older and postmenopausal and must have an increased risk of breast cancer as determined by their age, family history of breast cancer, personal medical history, age at first menstrual period, and age at first live birth. They will be randomly assigned to receive either 20 mg of tamoxifen daily or 60 mg of raloxifene daily for five years. They will receive close follow-up examinations, including mammograms, physical exams, and gynecologic exams, on a regular basis for at least seven years.

The National Surgical Adjuvant Breast and Bowel Project (NSABP), a National Cancer Institute (NCI)-sponsored research network based in Pittsburgh, will run the trial. NSABP has already selected the 193 main institutions who will participate in STAR, including sites in 48 states, six Canadian provinces, the District of Columbia, and Puerto Rico. These 193 institutions will form networks with other local physicians, creating an estimated 400 active centers participating in the trial.

Women who wish to be put on a mailing list for information about STAR can do so by Internet on the NSABP homepage ( http://www.nsabp.pitt.edu), by mail to NSABP, Box 21, Pittsburgh, PA 15261, or by fax to NSABP at (412) 330-4660. Once the trial has begun, women can get information from NCI's Cancer Information Service at 1-800-4-CANCER and the NCI Web site for clinical trials information ( http://cancertrials.nci.nih.gov).

For more information about cancer visit NCI's Web site for patients, public and the mass media at http://rex.nci.nih.gov or NCI's main Web site at http://www.nci.nih.gov.