Colonoscopy Prevents Deaths from Colon Cancer

For the first time, a new study has shown that removing polyps by colonoscopy not only prevents colorectal cancer from developing, but also prevents deaths from the disease. The collaborative study was led by researchers at Memorial Sloan-Kettering Cancer Center in New York City and included researchers at the Medical College of Wisconsin and six additional clinical centers.

The findings are published in the February 23 issue of the New England Journal of Medicine http://www.nejm.org/doi/full/10.1056/NEJMoa1100370#t=articleTop.

Researchers evaluated 2,602 patients enrolled in the National Polyp Study (NPS) who had precancerous polyps removed during colonoscopy. The patients in the study were evaluated for up to 23 years following the procedure. The detection and removal of these polyps resulted in a 53 percent reduction in colorectal cancer mortality compared to that of the deaths expected in the general population of comparable size, age, and gender.

Patients who had adenomatous polyps removed – polyps which are known to be associated with colon cancer-- also had the same low death rate from colorectal cancer for up to ten years after the procedure compared to a control group of people with no polyps.

“These findings provide solid evidence that there is a significant health benefit to removing these polyps, and support continued recommendation of preventive colonoscopy for patients age 50 and older,” said Walter J. Hogan, M.D., professor of medicine (gastroenterology and hepatology) at the Medical College of Wisconsin.

Randomized, controlled trials of screening colonoscopy are currently underway across the United States in Europe. Researchers believe those studies will eventually yield additional evidence in favor of this preventive procedure.

Edward Stewart, MD, professor emeritus of radiology at the Medical College, was a co-author of the study. In addition to Memorial Sloan Kettering Cancer Center and the Medical College of Wisconsin, the other clinical sites in the study were Mt. Sinai Medical Center (New York), Veterans Affairs Medical Center (Minneapolis), Massachusetts General Hospital (Boston, MA), Cedars-Sinai Medical Center (Los Angeles), and Presbyterian Hospital (Van Nuys, CA).