Novel approaches for chemoprevention of breast cancer are clinically attractive because many of the known risk factors associated with this devastating disease (e.g., family history and delayed menopause) are beyond human control and currently available chemopreventive options, such as selective estrogen receptor modulators (e.g., tamoxifen) and aromatase inhibitors, are sub-optimal [2]–[5]. This evidence concerns the gene ESR1 and breast carcinoma.