Technologies That Improve Adenoma Detection Rates

New colonoscopes and the emergence of AI make it easier for physicians to prevent long-term, potentially life-threatening complications.

Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. According to the American Cancer Society, the estimates of colorectal cancers in the U.S. for 2023 are 106,970 new cases of colon cancer and 46,050 new cases of rectal cancer.

What’s worse, many patients put off their colonoscopies during the COVID-19 pandemic, which led to more patients presenting with advanced-stage colon cancer. Plus, screening recommendations recently dropped from age 50 to age 45, so there are five extra years’ worth of new people to screen.

As providers, we need to be more vigilant than ever. That means equipping our facilities with the most effective technologies and top-performing colonoscopes that improve adenoma detection rates.

Before malignancy

The goal of colonoscopy is to identify and remove polyps before they can turn into a malignancy. Here are some of the latest advances that providers should consider to maximize their adenoma detection rates (ADRs).

• Disposable attachments. Distal attachment devices are disposable accessories that mount on the end of your current endoscopes and can increase the polyp detection rate five to 11 percentage points. Attached to the end of the colonoscope like a flower on a stem, they enhance your scope’s field of view with finger-like projections. They act like little arms that can pull back the folds of the colon to allow you to see in the areas where polyps are commonly missed. You can easily utilize one of these disposable attachments without the need to purchase new scopes or capital equipment. The benefit-cost ratio is good, as the attachments are low-cost and still aid in the provider’s ability to find more polyps.

• Field of view. Some endoscope companies have redesigned endoscopes to make polyp detection easier. For example, instead of a camera that looks forward with a 170-degree field of view, certain scopes are now designed with multiple cameras that look out of the sides of the scope as well. Basically, these scopes give you a 360-degree view in one integrated image.

Instead of looking around the corner with your scope tip to see around colonic folds, the scope’s integrated cameras do it for you — at all times. Think of it like this: Instead of looking at the colon with a telescope, you’re now looking at it with a periscope, only now you have four periscopes mounted all around, and you can see all of those images all at once on one screen. Unfortunately, this particular technological advancement requires the capital purchase of new endoscopes and processors, so if you are in the market for new colonoscopes or are looking to augment your current armamentarium these endoscopes may be right for you.

• Optical imaging technology. Narrow Band Imaging (NBI) is now a feature that comes standard on many endoscope processor units. By utilizing a button on the colonoscope or processor, the light source switches from shining white light on to the tissue to shining blue wavelengths of light, which are narrower. Narrow-band light does two things: 1.) It penetrates the tissue a little bit deeper, and 2.) It interacts with hemoglobin a little differently to show you the blood vessel pattern of something you are endoscopically observing.

This can help distinguish normal mucosa from adenomas or cancer. You can look at an area of the colon and you have a unique way of looking at it that provides different information to the endoscopist — without having to do anything other than hit a button. Sometimes when you hit that button, an irregularity suddenly stands out that under white light was there, but too subtle to clearly see. NBI is already built into many scopes, so this technology may already be in your hands. Endoscopists just need to start using it and understanding its applications and utility. Literature suggests it can increase adenoma detection rate five to 18 percentage points.

• Artificial intelligence-assisted colonoscopy. Whether you are ready or not, artificial intelligence (AI) is making its way into health care. Endoscopy companies have begun rolling out some version of AI to help you identify polyps. It works using a process called deep learning, which enables computer systems to learn how to identify objects. While endoscopists can tell you what a polyp looks like because of the folds and ridges on it, that is probably not what the computer algorithm is looking at. It’s probably looking at something totally different, like how the light interacts with the surface of the polyp, or how the polyp stands out in comparison to the surrounding mucosa. The exact information that AI is using to “see” a polyp is often not well understood, but these systems can increase ADR by 10-15%.

Where these algorithms work well is on the polyps that are hard to find, such as flat or subtle polyps that are small or hidden around the corner — not on polyps that are easy to find.

Ultimately, the question is: Can AI make an endoscopist better? That depends on the endoscopist. For an expert endoscopist with a high adenoma detection rate, AI has not demonstrated a capacity to make them better. However, recent studies suggest that AI is beneficial for individuals learning to do endoscopy and for individuals with a lower adenoma detection rate, improving their abilities to identify polyps at the same level as colonoscopy experts. AI could have an impact on endoscopist quality training, resulting in better efficacy of screening colonoscopies by reducing the incidence of interval or missed cancers.

SLOW DOWN The most cost-efficient way to find more polyps is for endoscopists to adequately survey all the mucosa through a combination of good technique and a longer withdrawal time.

To put it another way, think about the average person doing a colonoscopy. Half of all endoscopists are technically worse than that individual and half are better. With current AI technology, it is challenging to make a top-performing endoscopist better. But it can help assist the average and sub-average endoscopists in finding more polyps, and improve the quality of the endoscopic evaluations they are performing. Hopefully AI will continue to improve to the point where such providers can find the polyps before the expert. Many facility leaders are eagerly awaiting an era where the endoscopist does not even need to be physically present when the majority of the endoscopy is occurring. Imagine a self-propelled colonoscope that auto-advances through the colon to the cecum and self-withdraws after looking for polyps. When the device identifies pathology based off AI, it would alert the endoscopist that a polyp has been detected that requires endoscopic removal.

Current AI systems are a step in the progression toward such an automated endoscopy, but they already appear to help low-performing endoscopists improve their adenoma detection rates — and the benefits of this are significant.

Slow down

While there are a number of innovations on the market that are meant to increase polyp detection rate, my biggest piece of advice to endoscopists is: Slow Down. The most cost-efficient way to find more polyps is to adequately survey all the mucosa through a combination of good technique and a longer withdrawal time. One of the main quality metrics that we use when we talk about colonoscopy is a withdrawal time that is appropriate (e.g., >six minutes for a negative colonoscopic evaluation). However, there is clear evidence in the literature that increasing the withdrawal time to eight or nine minutes while emphasizing high-quality inspection methods can increase the ADR by up to 9%.

There are other simple technique changes shown to increase the ADR that can also be instituted quite simply. For example, retroflexion in the cecum can be accomplished 91% of the time and increases the ability to detect right sided adenomas by 17% with an overall low (0.03%) rate of complications. In those cases where retroflexion is not possible, or the endoscopist is not comfortable performing this maneuver, a second forward-viewing look of the right colon increases total ADR by 10%, including a 5% increase for right sided lesions that were missed on the first-pass endoscopy.

These are small changes and simple steps any endoscopist can make in their practice today.

They don’t require the purchase of new equipment or endoscopes, and they can help provide the best care for each and every one of your patients by preventing long-term and potentially life-threatening complications. OSM