The most appropriate time to repeat colonoscopy is in 5 years. Patients who undergo curative surgical resection for colon cancer should have a complete perioperative colonoscopy to remove all synchronous neoplasia. A subsequent surveillance colonoscopy is recommended within 1 year. If results of that colonoscopy are normal, repeat colonoscopy is recommended at 3 years, and, if normal, every 5 years thereafter. If colorectal polyps are detected, the surveillance interval should be based upon the number, size, and pathology of the polyps. This patient has received his 1- and 3-year follow-up colonoscopies and has had normal results; therefore, colonoscopy can now be repeated every 5 years.

A 10-year colonoscopy interval is appropriate for patients with a family history of adenoma or colorectal cancer in one first-degree relative or two second-degree relatives older than age 60 years. It is not recommended for this patient because his history of colorectal cancer requires more frequent surveillance.