A malignant tumor as a result of the inner wall of big intestine (the colon). In the US, a cancerous colon may be the 3rd leading style of cancer in males as well as the 4th in females. Risk aspects for a cancerous colon and colon (colorectal disease) consist of colon polyps, long-standing ulcerative colitis, and hereditary genealogy and family history. Most colorectal cancers develop from polyps. Removal of colon polyps can prevent colorectal disease. Colon polyps and very early cancer of the colon can have no symptoms. Therefore, regular testing is important, beginning at age 50 (or previous, if added threat factors can be found). Diagnosis are made by barium enema or by colonoscopy, with biopsy confirmation of cancer muscle. Surgery is the most common treatment for colorectal disease.