A diagnostic procedure for the detection of gastrointestinal problems, including colon cancer. Colon cancer is the second leading cause of cancer death in the United States. Aurora Clinic’s GI Endoscopy service offers patients access to an important screen for early detection and prevention of colon cancer. All adults age 50 and over should be screened for colon cancer. If you have a family history of colon cancer, you should start screen as early as age 40.