Background:Insulin like growth factor (IGF) system plays an important role in the development, proliferation, differentiation, survival, metabolism, and transformation of cells.Aim of the work:The aim of this study is to demonstrate the relationship between the level of IGF-1 and the increased incidence of colorectal cancer.Subjects and methods:The study included 68 subjects (40 colorectal cancer patients and 28 volunteers with no endoscopic evidence of colorectal cancer). Serum IGF-1 was measured for both groups using enzyme linked immunosorbent assay (ELISA).Results:Circulating IGF-1 significantly increased in patients with colorectal cancer (CRC) than controls. By assessing IGF-1 as a marker of colorectal cancer, IGF-1 showed the highest diagnostic performance at cut off value of 208.5 ng/ml (area under the ROC curve = 1, p = <0.01) at which sensitivity is 100% and specificity 100%. Conclusion:The results of this study suggest a positive correlation between the increased levels of IGF-1 and colon cancer and are thus consistent with the hypothesis that the level of IGF-1 plays an important role in the development of colon cancer.