The colon is a muscular tube that forms that last part of the digestive tract. It absorbs water and stores food waste. The last six inches of the colon are also known as the rectum. Sometimes colons develop polyps or cancer. Polyps are fleshy clumps of tissue that form on the lining of the colon or rectum. Most polyps are benign, however some polyps can change and become cancerous. Almost all colorectal cancers begin as a polyp.
A colonoscopy is the best test for finding polyps and cancer. Other tests such as blood tests, rectal exams and barium enemas may help your physician detect any suspicious growths. Other tests, such as CT or PET scans or ultrasound may be undertaken as well.