Trending Clinical Topic: Colonoscopy

Ryan Syrek


October 21, 2022

To address the importance of screening for CRC, actors Ryan Reynolds and Rob McElhenney recently raised awareness using a bit of humor. The two stars filmed their own colonoscopies for the Lead From Behind campaign. Both performers are now 45 years old, which is the new age at which many organizations now recommend men with average risk get their first colonoscopy. During the procedure, doctors identified and removed a polyp from Reynolds, which could have developed into something more serious over time. McElhenny's doctor found three polyps and removed them as well. These findings helped demonstrate the importance of screening younger men at average risk for CRC, said experts.

The preference that younger patients have about specific CRC screening types is "alarming" to some. David A. Johnson, MD, recently shared his concern about a study out of California. In an online survey, 1000 persons were asked about their preferences among the five CRC screening tests recommended by the US Multi-Society Task Force (US-MSTF). Results showed that the preference was consistent for multitargeted fecal immunochemical test (FIT)/fecal DNA testing in all patients. In a comparison of US-MSTF tier 1 screening tests, annual FIT testing was preferred by 68.9% among those aged 40-49 years and 77.4% among those aged 50 years or older, compared with only 31.1% and 22.6% for colonoscopy, respectively. Johnson points out that this is worrying because "FIT misses 95% of advanced lesions as it relates to sessile serrated polyps. When you talk about a 5% detection rate, that's within the element of chance."

What happens after FIT screening is also a concern. A new study found that adenoma detection rate (ADR) targets for endoscopists performing colonoscopy after a positive FIT result should be markedly higher compared with ADR targets used in primary colonoscopy. The ADR is a key quality indicator because it reflects the ability to detect lesions and is inversely associated with the risk for interval postcolonoscopy CRC (PCCRC). Adults with a positive FIT result have a high prevalence of adenomas, leading to high ADRs for endoscopists performing colonoscopies.

The study included 362 accredited and audited endoscopists who performed 116,360 colonoscopies. During a median follow-up of 52 months, 209 interval PCCRCs were identified. Endoscopists' ADRs ranged between 40% and 82%, with a median ADR of 67%. A higher ADR was strongly associated with lower incidence of interval PCCRC, with an adjusted hazard ratio of 0.95 (95% CI, 0.92-0.97) per 1% increase in ADR. For endoscopists with an ADR of 60%, the cumulative incidence of interval PCCRC was nearly two times as high as that of endoscopists with an ADR of 70%. For every 1000 FIT-positive colonoscopies, the expected number of patients diagnosed with interval PCCRC in 5 years was roughly 2 for endoscopists with an ADR of 70%, compared with almost 3.5 for ADRs of 60% and more than 4.5 for ADRs of 55%.

Yet another concern has to do with the use of artificial intelligence (AI) during colonoscopy, which may add to patient burden in terms of increased colonoscopy frequency and subsequent healthcare costs. A new study found that colonoscopy plus AI (vs colonoscopy alone) increased the proportion of patients requiring intensive postpolypectomy colonoscopy surveillance by roughly 35% in the United States and Japan and by about 20% in Europe. The study included 5796 patients: 2894 underwent AI-assisted colonoscopy and 2902 underwent standard colonoscopy without AI assistance. Higher ADRs in the AI-assisted colonoscopy groups were observed in all of the trials.

When the US and Japanese guidelines were followed, the proportion of patients recommended for intensive surveillance increased from 8.4% (95% CI, 7.4%-9.5%) in the non-AI group to 11.3% (95% CI, 10.2%-12.6%) in the AI group. When the European guidelines were followed, the increase was from 6.1% (95% CI, 5.3%-7.0%) to 7.4% (95% CI, 6.5%-8.4%). Researchers suggest that the increases are primarily due to the reclassification of patients from low-risk to intermediate- or high-risk categories. This shift is probably due to the AI-related increase in adenomas per colonoscopy. This may lead to more effective cancer prevention but also potential added patient burden and cost.

From new findings about the efficacy and impact of colonoscopies to an effective awareness campaign and emerging concerns, this screening tool has been the focus of much recent attention. The result is this week's top trending clinical topic.

Learn more about colonoscopies.


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