Efficacy of water pressure method for colorectal endoscopic submucosal dissection: a propensity-score matching analysis

Technical difficulty of endoscopic submucosal dissection (ESD) for colorectal neoplasms has not been resolved. The water pressure method (WPM) is a helpful technique for overcome difficulties with colorectal ESD. We evaluated the efficacy and safety of ESD with WPM (WPM-ESD) for colorectal neoplasms compared with conventional ESD (C-ESD). This was a single-center, retrospective, observational study. Three hundred and eleven colorectal lesions were allocated into the WPM-ESD and the C-ESD groups, which were compared before and after propensity score matching. The main outcomes were procedure time, proportion of R0 resection, and incidence of adverse events (AEs) in the two groups. The WPM-ESD and C-ESD groups were allocated 134 and 177 lesions, respectively, and propensity score matching analysis created 92 matched pairs. Mean procedure time was significantly shorter in the WPM-ESD group (49 ± 26 vs. 58 ± 42 min, P = 0.032). All lesions were resected in one piece and there was no difference in the proportion of en bloc resection (100% vs. 100%) and R0 resection (92% vs. 96%, P = 0.536) or in incidence of intraoperative perforation (2.2% vs. 2.2%) in the two groups. WPM for colorectal ESD may shorten procedure time compared with C-ESD without increasing AEs.