Colorectal Cancer Screening
Colorectal cancer screening is an important mission for a practicing gastroenterologist. It has assumed two goals: reduction of mortality due to colorectal cancer and prevention of colorectal cancer through the removal of polyps. Several different screening modalities are fecal occult blood testing (FOBT), flexible sigmoidoscopy, colonoscopy, barium enema, and, more recently, computed tomography (CT)-colonography and stool DNA tests. The two tests designed to detect blood in the stool are the guaiac-based fecal occult blood test (gFOBT) and the fecal immunochemical test (FIT). DNA-based stool tests are designed to test for the presence of DNA carrying some of the genetic mutations common in colorectal cancer. Flexible sigmoidoscopy has been associated with a significantly decreased risk of and mortality from colorectal cancer. Patients at high risk due to family history of cancer or polyps or a personal history of longstanding inflammatory bowel disease (IBD) should be encouraged to adhere to a regular program of surveillance through colonoscopy.
