Evaluation of metformin in early breast cancer: a modification of the traditional paradigm for clinical testing of anti-cancer agents

Metformin, an inexpensive oral agent commonly used to treat type 2 diabetes, has been garnering increasing attention as a potential anti-cancer agent. Preclinical, epidemiologic, and clinical evidences suggest that metformin may reduce overall cancer risk and mortality, with specific effects in breast cancer. The extensive clinical experience with metformin, coupled with its known (and modest) toxicity, has allowed the traditional process of …