APC and colorectal cancer: Evidence present that mortality from colorectal cancer can be reduced through early detection and removal of adenomatous polyps which are precursors for cancer development, digital rectal examination and fecal occult blood test have not been shown to reduce the mortality rates.Genetic abnormalities may cause alteration in the tumor suppressor genes such as P53, adenomatous polyposis coli gene (APC) and some other genes.