March 05, 2020
2 min read

Interval CRC rate inversely correlated with endoscopist adenoma detection rate

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As endoscopists improve their adenoma detection rates, the rate of interval colorectal cancer decreases, according to research published in Gastrointestinal Endoscopy.

Rajesh N. Keswani, MD, MS, of the department of gastroenterology at Northwestern University, and colleagues wrote that maintaining a high level of colonoscopy quality can be just as important as improving patient screening rates.

“Given the low overall incidence of interval CRC and multiple potential etiologies, measuring interval CRC rates for a group of colonoscopists (rather than an individual colonoscopist) may be the optimal colonoscopy quality indicator for a large practice,” they wrote. “Despite the importance of interval CRC rates, it is rarely measured.”

Researchers conducted a retrospective cohort study comprising data from 193,939 colonoscopies performed between 2003 and 2015 at an academic medical center. They identified interval CRC through a data warehouse and reviewed patient charts. They defined interval CRC as a cancer diagnosed between 6 and 60 months and early interval CRC as a cancer diagnosed between 6 and 36 months after index colonoscopy.

Investigators explored the relationship between provider adenoma detection rate and interval CRC rates and assessed interval CRC rates over time after the initiation of a quality improvement program that began at the center in 2010.

Keswani and colleagues identified 186 patients with interval CRC and determined the interval CRC and early interval CRC rates to 0.12% and 0.06%, respectively.

Patients at average risk who underwent colonoscopy with an endoscopist in the highest ADR quartile (34%–52%) were at lower risk for interval CRC (RR= 0.23; 95% CI, 0.11–0.48) compared with patients who underwent colonoscopy by a provider in the lowest ADR quartile (12%–21%).

After the quality improvement program was implemented, overall interval CRC rates improved from 0.15% to 0.08% (P < .001) and early interval CRC rates improved from 0.07% to 0.04% (P = .004).

Keswani and colleagues wrote that measuring interval CRC rates provides an opportunity to use the primary outcome of interest in screening colonoscopy to track colonoscopy quality.

“We report a feasible method to measure interval CRC rates for an institution or large group practice,” they wrote. “Our findings highlight the potential of measuring interval CRC rates to supplement existing markers of quality, including its use in a comprehensive approach to improving the effectiveness of screening colonoscopy.” – by Alex Young

Disclosure: Keswani reports consulting for Boston Scientific and Motus-GI. Please see the full study for all other authors’ relevant financial disclosures.