A colonoscopy is an examination of the inside lining of the colon, which is where colon cancer starts. During a colonoscopy, a long, narrow, flexible tube with an HD camera at the end is used to evaluate the rectum and colon.
Colonoscopies can detect conditions like colitis, inflammatory bowel disease and diverticulosis. But mainly, doctors are looking for precancerous or cancerous colon polyps, which are growths on the inside of the colon’s lining. If the doctors spot polyps, they can quickly and painlessly remove them during the same colonoscopy.