ABSTRACT
Chemoprevention of breast cancer The antiestrogenic properties of tamoxifen have been known since the 1960s. The ability of the compound to prevent the development of the hormonally responsive 7,12-dimethylbenz[a]-anthracene (DMBA)-induced tumor in rodents was recognized in the 1970s. Its clinical value in inducing remissions in metastatic and locally advanced breast cancer led to the establishment of trials seeking to demonstrate the efficacy of tamoxifen in the adjuvant setting. When the results of these studies displayed a convincing reduction in breast cancer in the opposite breast, it became a logical step to propose that the drug might be beneficial in the primary prevention of breast cancer.
