IGF1 and breast cancer: It has been predicted that the total number of adult patients with T2DM will increase from 170 million to 360 million from 2000 to 2030 globally.3 Furthermore, prior studies support that diabetes mellitus is one of the high-risk factors of breast cancer, 20% of such group of patients in the early stage have diabetes mellitus, and its related mechanisms include hyperglycemia, hyperinsulinemia, etc.4,5 Meanwhile, there is a cross-link of insulin and insulin-like growth factor-1 (IGF-1) with each other’s receptors.