If you’re going to go to the trouble of having a colonoscopy, you’d probably prefer that you get as much as you can out of the screening test. A new study this week shows that a doctor’s rate of finding and removing adenomas — these are pre-cancerous growths — is linked to the patient’s lower risk of developing colon cancer later.

Colonoscopy is one of the recommended screening tests for colon cancer. Yet doctors have differing rates at how often they find these adenomas. This is the first study in the U.S. to look at the association between finding adenomas and later cancer risk, as part of a national review funded by the National Cancer Institute. It was published in the New England Journal of Medicine.

In the study, researchers at Kaiser Permanente Northern California reviewed more than 300,000 colonoscopies performed by 136 gastroenterologists between 1998 and 2010.

The doctors’ detection rates for adenomas ranged from 7.4 percent to 52.5 percent. The researchers found that for every 1 percent increase in detection rate there was a 3 percent decrease in colon cancer risk over the next decade.

Dr. Douglas Corley is research scientist with Kaiser’s Department of Research and lead author of the study. “The (doctors) who were at the higher end of the detection, their patients were actually less likely in the future to be diagnosed with a colon cancer, an advanced colon cancer and to die of colon cancer,” he said.

Medicare is in the process of setting standards for doctors’ groups to report their detection of adenomas as a quality measure but “patients certainly ask their physicians if their groups measure adenoma detection rates” now, Corley said.

HealthDay spoke to a gastroenterologist not involved in the study who backed up Corley’s recommendation. From HealthDay:

“Many (doctors) make quality measures available to their patients,” said Dr. Lawrence Kim, who serves as the community private practice councilor for the American Gastroenterological Association (AGA).

That information may be in the written materials your doctor gives you, or even on the practice’s website, Kim said.

A “minimum threshold” for finding adenomas is at least 15 percent for women and 25 percent for men, Corley noted. Adenomas are more common in men. Most of the doctors in the study were above 20 percent overall. Kaiser is working to develop interventions to improve adenoma detection rates among all doctors, he said. Those interventions may ultimately be applied to physicians beyond Kaiser.

Your Doctor’s Skill at Colonoscopy May Reduce Your Later Colon Cancer Risk 8 April,2014Lisa Aliferis


Lisa Aliferis

Lisa Aliferis is the founding editor of KQED’s State of Health blog. Since 2011, she’s been writing and editing stories for the site. Before taking up blogging, she toiled for many years (more than we can count) producing health stories for television, including Dateline NBC and San Francisco’s CBS affiliate, KPIX-TV. She also wrote up a handy guide to the Affordable Care Act, especially for Californians. Her work has been honored for many awards. Most recently she was a finalist for “Best Topical Reporting” from the Online News Association. You can follow her on Twitter: @laliferis

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