Routine Proctosigmoidoscopy: How Often?

The cost-yield performance of routine proctosigmoidoscopy can be improved by far fewer examinations limited to the higher-risk patients. Since patients with diminutive polyps are at greater risk but diminutive polyps are rarely malignant and the doubling rate of colon cancer is slow, proctosigmoidoscopic examination of these higher-risk patients every 2 years is safe and more productive. Over 35% of those with original negative proctosigmoidoscopy demonstrate a new polyp on a second examination within 6 years. This significant shift into the higher-risk population warrants repeat proctosigmoidoscopy at least every 6 years in those without polyps.