Dynamic adenoma detection rate influences the risk of metachronous advanced neoplasia after removal of low-risk findings in screening colonoscopy

Background Endoscopists' adenoma detection rate (ADR) may change over time and dynamic ADR has been identified as a predictor for post-screening colorectal cancer. However, whether low-risk findings removed by an endoscopist with a lower dynamic ADR benefit from a shorter duration of follow-up requires further research. Methods We conducted a two-center retrospective study of individuals who had low-risk findings removed and underwent subsequent surveillance colonoscopy. Endoscopists' dynamic ADR was the ADR of the previous 100 screening colonoscopies performed by the same endoscopist. A Cox-regression model and Kaplan-Meier survival analysis were used to explore the relationship between dynamic ADR and metachronous advanced colorectal neoplasia (ACRN). Results Totally, 3471 individuals who had low-risk findings removed in baseline colonoscopy were included in analysis. Decreasing endoscopists' dynamic ADR was independently associated with metachronous ACRN. A 3.97-, 2.21-, and 2.67-fold increased risk for metachronous ACRN was observed in individuals of which baseline colonoscopy was performed by an endoscopist with a dynamic ADR of < 15%, 15-19%, and 20-24%, respectively, compared with those with the highest dynamic ADR (>= 25%). The cumulative incidence of metachronous ACRN reached the 5% threshold at 4.5 years, 7.3 years, and 6.2 years in the dynamic ADR < 15%, 15-19%, and 20-24% group, respectively. Conclusion Endoscopists' dynamic ADR influences the risk of metachronous ACRN after removal of low-risk findings in screening colonoscopy. Individuals undergoing removal of low-risk findings in screening colonoscopy by an endoscopist with a dynamic ADR < 25% may benefit from a shorter duration of follow-up interval.