The estrogen receptor: A logical target for the prevention of breast cancer with antiestrogens

A strategy for the prevention of breast cancer has been refined over the la st century beginning with the first observation that oophorectomy caused di sease regression in some patients, to the identification of the estrogen re ceptor some 60 years later, and finally to the synthesis of the first nonst eroidal antiestrogen. Tamoxifen was the first clinically useful antiestroge n and has been used for the treatment of breast cancer for the last twenty- one years in the United States. It is therefore a logical progression that antiestrogens are now recognized as useful agents for the prevention of bre ast cancer. We will discuss the estrogen receptor as a target for the treat ment and now the prevention of breast cancer. Data from the National Surgic al and Bowel Project (NSABP)(4) tamoxifen prevention trial will be discusse d with the preliminary results of two other European studies. The status of breast cancer prevention to date involves the comparison of the current st andard of prevention, tamoxifen, with the osteoporosis prevention drug, ral oxifene in an ongoing trial called Study of Tamoxifen and Raloxifene (STAR) .