The introduction of colorectal endoscopic submucosal hydrodissection at a Western Center: results and learning curve

Abstract

Background Colorectal endoscopic submucosal dissection (CR-ESD) is an evolving technique in Western countries. The use of hydrodissection has been established as an effective technique for safe resection. However, it is unknown if the adoption of this technique can help a novice perform ESD safely without prior experience or formal tutorial. Here we aimed to determine the results of the introduction of endoscopic submucosal hydrodissection for the treatment of complex colorectal polyps and establish the learning curve for this technique, at a European tertiary hospital. Methods This study included data from 80 consecutive CR-ESDs performed for complex colorectal polyps, by a single endoscopist within a structured training program. The main outcome was en bloc resection rate, while secondary outcomes included complications (perforation and bleeding), knife en bloc (KEB) resection rate, knife-snare en bloc resection rate, conversion rate to endoscopic piecemeal mucosal resection (EPMR), complete resection rate, curative resection rate. To explore the impact of experience, procedures were divided into 4 groups of 20 each, with outcomes measures compared between these. Results The overall en bloc resection rate was 75%. KEB resection was obtained in 15%, 25%, 50%, and 80% cases in the consecutive periods (period 1 vs 4, p<0.001; periods 1, 2 and 3 vs 4, p<0.001). Conversion rate to EPMR was obtained in 40%, 25%, 25% and 5% respectively (period 1,2 and 3 vs 4; p=0.031). Curative resection was achieved in 55%, 75%, 70% and 95% respectively (p=0.037). Series results were 75% R0 resection, 23.7% conversion to EPMR, and 1.2% incomplete resection. Complications included perforations (7.5%) and bleeding (3.75%), there was no significant difference in the 4 periods of training. Multivariate analysis revealed factors more likely to result in non-en bloc versus en bloc resection were polyp size > 35 mm [70% vs. 23.4%; OR 13.2 (95% CI: 1.7-100.9); p=0. 013], severe fibrosis [40% vs. 11.7%; OR 10.2 (95% CI: 1.2-86.3); p= 0.033] and non-use of CO2 [65% vs. 30%; OR 0.09 (95% CI: 0.01-0.53); p= 0.008]. Conclusions CR-ESD by hydrodissection can be implemented in a western centre and offers safe and effective treatment for complex polyps.