A malignant tumor due to the inner wall of the end associated with the large intestine (colon). In the US, it's the third leading reason behind cancer tumors in males while the fourth in females. Risk factors consist of heredity, colon polyps, and long-standing ulcerative colitis. Many rectal types of cancer develop from polyps in the colon. Removal of these polyps can possibly prevent disease. Colon polyps and early rectal cancer have no symptoms, so regular evaluating is important. Diagnosis could be made by barium enema or by colonoscopy, with biopsy confirmation of disease structure. Procedure is considered the most common treatment.