Su1070 ENDOSCOPIC SUBMUCOSAL DISSECTION FOR COLORECTAL LATERALLY SPREADING TUMORS: CLINICAL OUTCOMES AND PREDICTORS OF TECHNICAL DIFFICULTY

Abstract

Endoscopic submucosal dissection (ESD) has been used for colorectal laterally spreading tumors (LSTs), yet is technically challenging. We aimed to investigate the clinical outcomes of ESD for colorectal LSTs and predictors of technical difficulty. Consecutive patients who underwent ESD for colorectal LSTs in Beijing Friendship Hospital between June 2013 and March 2019 were retrospectively involved. We evaluated the en bloc resection rate, R0 resection rate, curative resection rate and adverse events with per lesion analysis. Dissection with a slow speed (<8mm2/min), conversion to piecemeal resection or abandonment of endoscopic procedure was considered as technically difficult. Factors associated with difficult ESD procedure, including LST subtype, size, non-lifting sign, procedure duration and operator experience (scaled by prior ESD case numbers) were determined using logistic regression. Significant factors with p<0.05 were adjusted in multivariate logistic regression. A total of 322 patients (56.5% men, mean age 64.7 years old) with 335 colorectal LSTs (median size 20.0mm, range 10.0-100.0mm) were enrolled. The proportions of granular (G) subtype and the non-granular (NG) subtype LSTs were 61.9% and 38.1%, respectively (Table 1). The en bloc, R0 and curative resection rate were 90.7%, 76.1% and 73.4%, respectively. The median dissection speed was 8.2mm2/min. Endoscopic procedure was abandoned in 4 lesions (1.2%), and 27 (8.1%) converted to piecemeal resection because of technical difficulty. Four cases (1.2%) had delayed bleeding and treated under endoscopy successfully. Perforation occurred in 10 LSTs (3.0%), of which only 1 (0.3%) needed surgery. Table 2 listed the risk factors for technically difficult ESD. NG subtype (odds ratio [OR] 1.9, p=0.012), positive non-lifting sign (OR 3.2, p=0.012), and less experienced operators (≤60 colorectal ESD cases) (OR 1.8, p=0.019) associated with a slow dissection speed. After adjusted in multivariate analysis, NG subtype (OR 2.2, p=0.004), positive non-lifting sign (OR 3.4, p=0.009), and less experienced operators (OR 2.1, p=0.009) remained to be independent predictors of low speed procedure. Lesions with size ≥20mm (OR 3.6, p=0.004) and positive non-lifting sign (OR 7.5, p<0.001) had higher risk for ESD abandonment or conversion to piecemeal resection due to difficult procedure. After adjustment in multivariate analysis, larger size (OR 8.3, p<0.001) and positive non-lifting sign (OR 13.3, p<0.001) were still significant factors. Procedure with prolonged duration of ≥60min associated with perforation (OR 5.8, p=0.014). ESD is feasible and safe for treating colorectal LSTs. NG subtype, larger size and positive non-lifting sign indicate difficult ESD procedure. The dissection speed can be improved with operator experience increased.View Large Image Figure ViewerDownload Hi-res image Download (PPT)