The Frequency of Screening Colonoscopies

Dr. Timothy Hoops
Last Modified: November 1, 2001

Dear OncoLink "Ask the Experts,"
How often do you recommend having a colonoscopy? I previously lived in NJ and the doctor there recommended every two years. I now live in NC and the doctor recommends every 5 years. Since I have a history of color cancer on both sides of my family, I am concerned.
Thank you,
A.W.

Dr. Timothy Hoops, Clinical Assistant Professor of Medicine in the Gastroenterology Division at the University of Pennsylvania and Director of Gastroenterology at Penn Medicine at Radnor, responds:

There are no absolute guidelines for the frequency of colonoscopies when one is doing them for average risk screening. Medicare has just released guidelines stating that they will reimburse for screening colonoscopies every 10 years. Flexible sigmoidoscopies have been recommended every 4 to 5 years and some physicians have extrapolated that to colonoscopies.

For people with an increased risk for cancer, the guidelines are clearer. For those with a history of colonic polyps, colonoscopies should be performed every 3 to 5 years, based on the findings of the last colonoscopy. For those with a history of colon cancer, a repeat procedure should be done at 1 year, and if negative, either at 2 or 3 years after that. If the procedures show no new polyps or cancers, the interval can safely be stretched to 3 to 5 years. Patients with a family history of colon cancer should have a colonoscopy every 5 years if they have no polyps and every 3 years if they do.

Please understand that while some of these recommendations are based on studies designed to answer these questions, some of the recommendations are based on expert opinion with indirect data for support. Your physician should determine the appropriate interval for your screening procedures based on your results.