Serum IGFBP‐3 levels in lung cancer patients were found to be lower than those of controls;6 however, in breast cancer, IGFBP‐3 expression induced mammary cell growth.7 Tas also reported that serum IGFBP‐3 might be a complement marker for CA125 in epithelial ovarian cancer diagnosis.8 In addition, IGFBP‐3 expression was found to be lower in pancreatic cancer patients than that of controls.9 However, the relationship between serum IGFBP‐3 and CRC has not been reported yet. Here, IGFBP3 is linked to breast cancer.