Colorectal Cancer Screening: Which Tests, How Often?February 1st 2007
ABSTRACT: Screening options for colorectal cancer (CRC) include colonoscopy every 10 years, annual fecal occult blood testing, flexible sigmoidoscopy every 5 years, or double contrast barium enema every 5 years. In white patients at average risk, screening should begin at age 50; in African American patients, at age 45. Colonoscopy is preferred to sigmoidoscopy because it can detect proximal neoplasms and has the longest protection interval. High-risk patients include those with a family history of CRC or adenomas. These persons should begin colonoscopic screening at age 40, or 10 years earlier than the age at which CRC or adenomas were diagnosed in a first-degree relative. Other high-risk patients are those with a personal history of CRC, a genetic syndrome, or inflammatory bowel disease. In patients with CRC, the first follow-up colonoscopy is performed 1 year after surgery. If results are normal, the interval can be extended to every 3 years.