The most significant correlation between increased levels of IGF-1 and the risk of cancer diagnosis was found for prostate cancer, pre-menopausal breast cancer, and colorectal cancer (Wolk et al., 1998; Ma et al., 1999; Giovannucci et al., 2000; Harman et al., 2000; Kaaks et al., 2000; Stattin et al., 2000; Chan et al., 2002; Palmqvist et al., 2002; Chen et al., 2009; Major et al., 2010; Rinaldi et al., 2010). Here, IGF1 is linked to breast cancer.