Here’s a bit of interesting information!
Physicians who perform colonoscopies can miss as many as 90% of precancerous colorectal lesions! That’s truly interesting but definitely disturbing. To think that you could have a colonoscopy and still have colorectal cancer because the endoscopist either completely missed, or didn’t recognize, a lesion, that later became a colorectal cancer, is worrisome. In fact, it’s tragic.
From this, it appears that colonoscopists are not perfect. It also indicates that some are far better at identifying precancerous colon lesions than others. How do we know our doctor is one of the good ones? To answer this important question, a U.S. Multi-society Task Force in conjunction with the American College of Gastroenterology and the American Society of Gastrointestinal Endoscopy, devised a standard by which endoscopists could be judged. This measure is called the adenoma detection rate, or ADR, and quantifies a physician’s ability to recognize precancerous adenomas. ADR has become the standard by which the competence of endoscopists is assessed.
ADR is defined currently as “the fraction [percentage] of patients aged 50 years and older undergoing first-time screening colonoscopy who have at least one conventional adenoma detected by a colonoscopist….ADR is considered the most important measure of colonoscopy quality…” In other words, if a colonoscopist does not find a precancerous adenoma in 30% of men and 20% of women he scopes, his performance is substandard. He/she maybe missing lesions.
The problem is if the colonoscopist has a high number of patients he scopes for the first time who are later found to have colorectal cancer, those adenomas were probably missed on the prior exam. The doctor didn’t recognize them as abnormal or just didn’t find them. The adenoma detection rate for this doctor would be low and his/her capability would come into serious question. A study in California and Washington showed “that higher physician ADR was associated with lower risk of postcolonoscopy colorectal cancer (PCCRC)……
increases in physician ADR’s were associated with lower risks of PCCRC and fatal lesions.”
The bottom line of this article is that there is now a measure to determine the competence of colonoscopists. Adenoma detection rate, ADR, is that standard. The numbers quoted are for screening, ie. first-time, colonoscopies. ADR’s for surveillance colonoscopies, or follow-up colonoscopies (for patients with prior adenomas), are higher than screening ADR’s for obvious reasons.
Determining adenoma detection rates is the new way physician practices, hospitals, and endoscopy centers can evaluate the ability of its physicians and improve quality of care. If a doctor does an average number of colonoscopies yet has a high percentage of patients who are later found to have colorectal cancer, that doctor has a low ADR and is missing more precancerous lesions than he/she should. No precancerous lesions should be missed because missed adenomas later develop into invasive cancers. This measure gives institutions an objective reason to limit the number of procedures an endoscopist performs and/or forces that physician to undergo additional training to improve his/her accuracy. That’s what residency and fellowship training programs are supposed to do, but don’t always accomplish.
Addendum: I don’t know if the ADR is being used by hospitals, clinics, or practice groups for peer review. The article did not say. If you were wondering about your physician’s rating, though, you could ask him/her directly. Another option is to contact either the American College of Gastroenterology or the American Society of Gastrointestinal Endoscopy for the data on your endoscopist. The author of this article is a well-known and highly-respected gastroenterologist who has done extensive research on colonoscopy. He is on the faculty of Indiana University School of Medicine.
Reference: Rex DK, Adenoma Detection Rate and Colorectal Cancer Prevention by Colonoscopy. JAMA 2022 June 7;327(21):2088-2089.
Rex DK, Schoenfeld PS, Cohen J et al. Quality Indicators for Colonoscopy. Gastrointestinal Endoscopist 2015;81(1):31-53.
