This transcript has been edited for clarity.
When it comes to the use of colonoscopy to reduce the risk for cancer, quality is key.
There are a number of performance improvements we can make in our practices so that we can do better. This is evident in several recently published studies and a recent review article on the topic, which I’d like to profile for you; many of these key quality indicators you can implement now.
Even though it may take more time before they’re supported in the guidelines, you’ll see that the evidence behind these is extraordinarily strong.
Increasing the Adenoma Detection Rate
Certainly, we all do what we can to increase the adenoma detection rate (ADR).
However, at the moment, the nationally recommended benchmark is to achieve an ADR of 25%, which is inordinately low. The ADR rate reported in the GIQuIC registry data is closer to 39%, and in high-level detectors, it’s actually in the greater-than-50% range.
There’s no question that we can do more, and there are a number of ways to do that.
First, This may actually decrease your withdrawal time because you don’t spend so much time trying to face these folds.
In considering tools to aid ADR, don’t forget electronic chromoendoscopy (eg, narrow-band imaging).
There are a number of new artificial intelligence options out there as well, which have been reported to increase the ADR by approximately 10%. Of importance, this improvement even occurs among expert endoscopists.
There’s also important emerging data about ADR in fecal immunochemical test (FIT)–positive patients. FIT-positive status increases the ADR threshold by 15%-20%. This places you in an ADR range of approximately 50%, which is really the norm when screening patients that present for colonoscopy because of FIT positivity.
Adenoma Per Colonoscopy: A Possible ADR Substitute
Growing evidence supports the use of adenoma per colonoscopy (APC) as a substitute to ADR. This would allow you to record every adenoma and attribute it to that index colonoscopy.
A high-quality paper showed that the APC value should be around 0.6 to achieve the current ADR minimum threshold of 25%. Having the APC < 0.6 seems to be associated with an increased risk for residual polyp. Sessile serrated lesions also increased the hazard ratio for interval colorectal cancer. This was evaluated recently with data from the New Hampshire Colonoscopy Registry, which Dr Joseph Anderson has led for so long. They showed that 21% of endoscopists had an ADR of 25% or greater but still had APCs < 0.6.
Therefore, when it comes to remedial corrective work, doctors need to be reevaluated, retrained, and educated in the ways that they can incorporate this. The APC in high-level detectors is > 1.0.
APC may be something you want to consider using internally. It does require that you place each polyp into an individual jar, which can increase incremental cost. Nonetheless, there is clear evidence that APC positively changes outcomes.
Including Sessile Serrated Lesions in ADR Detectors
Unfortunately, some of the high-level ADR detectors aren’t so “high level” when it comes to detecting sessile serrated lesions. It’s not quite as concordant as we had previously thought.
Nonetheless, there are many adjunctive things you can do with sessile serrated lesions, including narrow-band imaging and chromoendoscopy.
When it comes to establishing a discriminant, the numbers should be 5%-6% if we’re going to set a quality ratio and an index. However, this is somewhat dependent on your pathologist because they have to read these correctly. Lesions that are ≥ 6 mm above the sigmoid colon and anything in the right colon should be evaluated really closely as a sessile serrated lesion.
I’ve had indications where the pathologist says the lesion is hyperplastic, to which I say, “I’m going to follow as a sessile serrated lesion.” This is because it’s apparent to me in the endoscopic appearance and the narrow-band imaging appearance that it was characteristic of sessile serrated lesions.
Best Practices in Bowel Preparations
The US Multi-Society Task Force recommends that adequate bowel preparation should occur in 85% or more of outpatients, and for the European Society for Gastrointestinal Endoscopy, it’s 90% or more.
I’ll pass along a tip I use in my patients undergoing bowel preparation: I make them aware that during this process, they want to see a clear, yellow, urine-like color to their stool. Otherwise, many patients will think if they’ve had some diarrhea, they don’t need to finish prep. Setting that expectation for them upfront is really important.
The nurses also should be aware of this because if there’s a murky brown effluent upon presentation for the colonoscopy, there’s a greater than 50% chance that they’re going to have had an inadequate preparation. In such cases, you would want to preempt the colonoscopy and perhaps send them out for a re-prep that day or bring them back for a rescheduled appointment.
Resection Considerations
There is substantial variation when it comes to lesion resection, which makes it an important quality indicator on which to focus: High-level detectors aren’t always high-level resectors.
There are two validated instruments that you can use to gauge the adequacy of resection. Those aren’t really ready for prime time in every practice, though they may be seen in fellowship programs.
The idea here is that you want to get a ≥ 2 mm margin for cold snare polypectomy in lesions 1-10 mm in size. This has been a challenge, as findings indicate we don’t do this that well.
Joseph Anderson and colleagues recently published a study using a 2-mm resection margin. They reported that this was only possible in approximately 28% of polyps. For a 1-mm margin, the rate was 84%.
We simply need to set clearer margins when setting our snare. Make sure you’re close enough to the polyp, push down on the snare, and get a good margin of tissue.
When the sample contracts are placed into the formalin, it’s not quite so simple to define the margin at the time of the surgical resection. This often requires an audit evaluation by the pathologist.
There are two other considerations regarding resection.
The first is about the referral for surgery. Referral should not occur for any benign lesions ascribed by your endoscopic advanced imaging techniques and classifications that are not thought to have intramucosal carcinoma. These should be referred to an expert endoscopic evaluation. If you can’t do it, then somebody else should. And you shouldn’t attempt it unless you can get it totally because resection of partially resected lesions is much more complicated. The European Society of Gastrointestinal Endoscopy says this applies to any benign lesion of any size, which I think really is the emerging standard of care. You should consider and offer that to the patient. It may require a referral for outside of your institution.
The second additional consideration is around the minimization of cold forceps for removal of polyps. The US Multi-Society Task Force says cold forceps shouldn’t be used for any lesions > 2 mm, whereas for the European Society of Gastrointestinal Endoscopy, it is > 3 mm. However, it’s still done very commonly in clinical practice. Nibbling the polyp is not an option. Cold snare is actually quicker, more effective, has better outcomes, and is something that you can bill for when you look at the coding.
In summary, there are a lot of things that we can do now to improve colonoscopy. Quality indicators continue to emerge with a compelling, excellent evidence base that strongly supports their use. Given that, I think most of these are actionable now, and it’s not necessary to wait for the guidelines to begin using them. I’d therefore challenge all of us to incorporate them in our continual efforts to do better.
Dr. Johnson is professor of medicine and chief of gastroenterology at Eastern Virginia Medical School in Norfolk, and a past president of the American College of Gastroenterology. His primary focus is the clinical practice of gastroenterology. He has published extensively in the internal medicine/gastroenterology literature, with principal research interests in esophageal and colon disease, and more recently in sleep and microbiome effects on gastrointestinal health and disease. He has disclosed ties with ISOTHRIVE and Johnson & Johnson.
A version of this article appeared on Medscape.com.