1567P - Physicians' adenoma detection rate and the risk of colorectal cancer in sequential screening programs: An observational cohort study

Background

Long-term colorectal cancer (CRC) monitoring is common in Asia, but assessing colonoscopy effectiveness by adenoma detection rates (ADR) remains rare. The objective of this study was to evaluate the relationship between physician ADR and PCCRC incidence in sequential screening programs in order to provide up-to-date clinical evidence relevant to guiding CRC screening policies and practices.

Methods

This retrospective longitudinal observational study included participants (aged 40-74) with initial positive results and subsequent colonoscopy recruited from a community-based, multicenter, CRC screening program from January 2012 and December 2022 in Tianjin, China. ADR was defined as the proportion of colonoscopies in which at least 1 adenoma was detected. The primary outcome was PCCRC, defined as any CRC diagnosed 6 months after initial colonoscopy. ADR groups were categorized according to quartile distribution <42%, 42%-55%, 55%-64%, >64%), or dichotomized as at or above vs below the median for statistical analyses. PCCRC incidence rates were expressed as the number of events per 1000 person-years.

Results

Among 9957 included participants, 116 PCCRC cases were detected in 33881 person-years of follow-up. PCCRC incidence rates were per 1000 person-years were 4.34, 3.76, 2.62, and 2.69 from lowest to highest ADR group, respectively. ADR was significantly inversely associated with risk of PCCRC. Participants in the highest ADR group had 49% lower risk of PCCRC than low ADR group subjects (adjusted HR: 0.51, 95% CI 0.29-0.88). Multivariate-adjusted restricted cubic spline analyses identified a linear dose-response relationship between ADR and PCCRC risk.

Conclusions

Our findings show that ADR is inversely associated with risks of both PCCRC and interval PCCRC incidence, expanding the currently limited pool of data available for assessment of colonoscopy-based CRC monitoring programs.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

This work was supported by the National Natural Science Foundation of China (Grant number: 81973135), Science and Technology Commission of Shanghai Municipality (Grant number: 21XD1402600), and Tianjin Science and Technology Plan Project (Grant number: 23KPHDRC00260).

Disclosure

All authors have declared no conflicts of interest.