Flexible sigmoidoscopy is done to detect cancer in the portion of the colon closed to the rectum and anus. This region is called the 'sigmoid colon'. A small tube containing viewing equipment is placed through the anus into the colon. As the tube is slowly removed from the colon, the doctor looks for any abnormalities. If a polyp or other abnormality is identified, a biopsy may be taken to test for the presence of cancer. Polyps may also be removed. If polyps are detected, a full colonoscopy may be recommended to check the entire colon and remove any additional polyps. There are rarely any major complications, but feeling bloated and cramping is normal. A patient experiencing chills, fever, or excessive rectal bleeding (a small amount is normal after this procedure) should seek medical attention.(1)