Novel concepts for the chemoprevention of breast cancer through aromatase inhibition.

Aromatase inhibitors (AIs) have a proven role in the treatment of early and metastatic breast cancer. The success of tamoxifen in reducing the relative risk of developing hormone-sensitive breast cancer in chemoprevention trials has been hampered by their long-term toxicity profile. AIs have the potential to further reduce rates of breast cancer in high-risk postmenopausal women. This article reviews the evidence to support the potential efficacy of AIs in the chemoprevention setting. It particularly focuses on a discussion of novel concepts of utilising AIs, so that they reduce breast cancer risk while minimising systemic toxicity, and highlights the importance of accurately developing risk prediction algorithms.