Breast cancer and diabetes mellitus

Breast cancer is the leading neoplastic malignancy among females worldwide. Another major health problem in industrial countries is diabetes mellitus type 2, both with a raising tendency. Up to 16% of the elderly breast cancer patients additionally suffer from diabetes. Epidemiologic studies suggest that type 2 diabetes increases breast cancer risk and goes along with an increased mortality however, there has been limited experimental evidence supporting this association. In the present review we summarized epidemiological data on a correlation between diabetes and breast cancer. Further, the diverse hypothesized molecular investigations and purposed mechanisms are recapitulated. The latest discussions on insulin and its enhancement of cancer rates among patients with diabetes have also toughed the breast cancer sector. In contrary, recent data indicate a benefit of breast cancer treatment due to metformin therapy. A large amount of literature is available and provides concepts for future research that is needed to rule out possible overlapping pathomechanism, prognostic factors, therapy interactions as well as possible synergistic or additive or even controversial interaction of chemotherapy and diabetes medication.