In a multiethnic, prospective cohort study of 600 women diagnosed with stage I–IIIA breast cancer, high serum levels of IGF1, and IGF1/IGFBP3 ratio were associated with increased risk of all-cause mortality (10), whereas, the majority of other studies did not support an association of higher levels of IGF1 and IGFBP3 with adverse prognosis of breast cancer such as all-cause mortality, breast cancer-specific mortality, and breast cancer recurrence (11–13). This evidence concerns the gene IGF1 and breast cancer.