Introduction: There is scarce data focused on recurrence neoplasia rate (RR) after piecemeal endoscopic mucosal resection (pEMR) of 10-19 mm non-pedunculated colorectal lesions (NPL). We aimed to analyze the RR after pEMR of 10-19 mm NPL, identify risk factors for its development and compare it with RR after pEMR of ≥ 20 mm NPL.
Methods: Retrospective cohort-study including all ≥10 mm NPL resected by pEMR in our center between 2018-2022 with an early repeat colonoscopy (ERC). RR was defined as recurrence neoplasia identified in the ERC EMR scar with virtual chromoendoscopy or histological confirmation.
Results: A total of 444 NPL were assessed, 124 (27.9%) with 10-19 mm. In the ERC, performed a median of 6 months after pEMR, RR was significantly lower for 10-19 mm NPL compared to ≥ 20 mm NPL (13/124 vs 68/320, p = 0.005). In subgroup analysis, RR after pEMR of 15-19 mm NPL was significantly higher compared to 10-14 mm NPL (13/98 vs 0, p = 0.041) but not significantly different compared to ≥ 20 mm NPL (13/98 vs 68/320, p = 0.073). In multivariable analysis, size of NPL (HR 1.501, 95% CI 1.012-2.227, p = 0.044) was the only independent risk factor identified for RR for 10-19 mm NPL.
Conclusion: Although the early RR after pEMR of 10-19 mm NPL is significantly lower compared to ≥ 20 mm NPL, it is non-negligible (10.5%) and appears to be the highest among 15-19 mm NPL. The size of the lesion was the only independent risk factor for RR. Our findings should be accounted in the selection of the most appropriate post-polypectomy endoscopic surveillance.
Keywords: Piecemeal resection; colorectal polyps; endoscopic mucosal resection; recurrence rate.