People who have had colonoscopy or sigmoidoscopy to remove low-risk colorectal polyps may have no greater risk of dying from colon cancer than the general public and likely do not need frequent follow-up colonoscopies, according to new findings by Harvard School of Public Health (HSPH) researchers and colleagues.

The researchers, including Dr. Mette Kalager, visiting scientist in HSPH’s department of epidemiology, followed nearly 41,000 patients in Norway who had colorectal polyps removed between 1993 and 2007, and tracked how many died from colon cancer through 2011. Those who had a single polyp smaller than a centimeter removed had a 25 percent reduced chance of death from colon cancer, compared to the general population. On the other hand, patients with more than one polyp or larger polyps had a 16 percent higher chance of dying from colon cancer.

The study, the largest and longest-running of its kind, was published August 28 in the New England Journal of Medicine.

Although current American Cancer Society guidelines call for more frequent follow-up colonoscopies for low-risk patients following polyp removal, the researchers suggest screening guidelines more in line with those for the general population — every ten years. Read more