Safety and efficacy of water pressure endoscopic submucosal dissection for colorectal tumors with submucosal fibrosis (with video)

Colorectal neoplasms with submucosal fibrosis are the most challenging targets of endoscopic resection. Water pressure endoscopic submucosal dissection (WP-ESD) is a recently introduced procedure that has several advantages over conventional endoscopic submucosal dissection (C-ESD). This study aimed to assess the efficacy and safety of WP-ESD for fibrotic colorectal neoplasms. This retrospective observational study investigated 133 colorectal neoplasms expected to have submucosal fibrosis that were resected by WP-ESD or C-ESD between April 2012 and April 2020. Eighty-seven lesions after endoscopic or surgical treatment, 18 with biopsy scar with fold convergence and 28 in patients with ulcerative colitis, were included. The differences in treatment outcomes, including procedure time and adverse event proportions, between the WP-ESD and C-ESD groups were analyzed. The clinical course after perforation using WP-ESD was also evaluated, including postprocedural multidetector CT findings obtained immediately after WP-ESD. Severe submucosal fibrosis was observed in 96 lesions (72.2%). The median procedure time was significantly shorter in the WP-ESD group than in the C-ESD group (43.5 minutes [interquartile range {IQR}, 32.8-73] vs 72 minutes [IQR, 45-105]; P = .0041). The multivariate analysis revealed WP-ESD as an independent factor for a short procedure time (odds ratio, 2.90; 95% confidence interval, 1.28-6.55). The proportions of post-ESD electrocoagulation syndrome (11.6% vs 13.1%) and perforation (20.4% vs 22.8%) were similar between the groups. Four of 11 patients with perforation who underwent WP-ESD showed fluid collection on postprocedural multidetector CT images. WP-ESD can shorten procedure time for treating fibrotic colorectal neoplasms.