Brief Class on Easy-to-Miss Precancerous Polyps Ups Detection, Mayo Study Shows

Most people know a colonoscopy requires some preparation by the patient. Now, a Mayo Clinic physician suggests an additional step to lower the risk of colorectal cancer: Ask for your doctor's success rate detecting easy-to-miss polyps called adenomas.

The measure of success is called the adenoma detection rate, or ADR, and has been linked to a reduced risk of developing a new cancer after the colonoscopy. The current recommended national benchmark is at least 20 percent, which means that an endoscopist should be able to detect adenomas in at least 1 of 5 patients getting a colonoscopy.

Recently, the Mayo Clinic in Florida developed a two-hour course designed to increase a doctor's ADR rate in order to reduce development of colorectal cancer.

They found the short course made a big difference in even experienced endocopsists, the physicians who perform colonoscopies.

"Numerous studies have shown that increased detection and removal of potentially precancerous polyps lowers the incidence of colorectal cancer," says Michael Wallace, M.D., M.P.H., chair of the Division of Gastroenterology and Hepatology at Mayo Clinic in Florida. "We also know that there is a lot of variability in how proficient physicians are at finding those polyps."

A team of Mayo physicians and researchers led by Dr. Wallace, has long been working to help endoscopists better detect polyps. Their findings are published in the Jan. 8 online issue of the American Journal of Gastroenterology.

Dr. Wallace and his team developed a two-hour training course that describes polyps that can be difficult to see, such as flat lesions, but are often the most dangerous.

The research team turned to Mayo Clinic endoscopists to study whether the course helps. Researchers first looked at the adenoma detection rate in 15 physicians and found it was 35 percent — almost twice the national average.

Then, seven endoscopists were randomly chosen to take the course, and detection rate was then measured in all of the endoscopists — those who took the course and the eight who didn't. Over the course of the study, these physicians performed 2,400 colonoscopies.

The researchers found that the endoscopists who took the course improved their adenoma detection rate to 47 percent, while the rate remained 35 percent among the doctors who did not take the course.

"This relatively simple education program substantially increased the proficiency of physicians who are already skilled," Dr. Wallace says. "Many people in the field think it is hard to change an endoscopist's level of proficiency, but we show that is not the case."

Dr. Wallace is now seeking to test the benefit of the short training course in a wider range of non-academic, community-based physicians — the doctors who perform most colonoscopies.