Q: Why do some patients have a colonoscopy performed every 10 years and some every five years?

A: For patients with no symptoms and no family history of colon cancer, current guidelines suggest a screening colonoscopy every 10 years is the optimal strategy. Other screening options include an annual stool test for microscopic blood, flexible sigmoidoscopy every five years or barium enema every 10 years. Remem-ber, these screening strategies are for individuals with no symptoms. Some patients have a higher risk for colon cancer. The best example is an individual with a first-degree family member with colon cancer, especially at a young age. These patients should be screened at five-year intervals. For patients who have precancerous, or adenomatous, polyps removed, the interval may change based upon the number, size and types of polyps found. Because prior precancerous polyps have been found and removed, this is called a surveillance examination, as such a patient is more likely to develop precancerous polyps in the future. Check with the physician who has performed your colonoscopy to determine the appropriate screening interval for you.

-- Dr. Colleen M. Schmitt, Galen Gastroenterology

and Digestive Health; member,

Chattanooga-Hamilton County Medical Society

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