Is underwater endoscopic mucosal resection of colon polyps superior to conventional techniques? A network analysis of endoscopic mucosal resection and submucosal dissection

Abstract

Background and study aims Evidence from recent trials comparing conventional endoscopic mucosal resection (EMR) to underwater EMR (UEMR) have matured. However, studies comparing UEMR to endoscopic submucosal dissection (ESD) are lacking. Hence, we sought to conduct a comprehensive network meta-analysis to compare the efficacy of UEMR, ESD, and EMR. Methods Embase and Medline databases were searched from inception to December 2020 for articles comparing UEMR with EMR and ESD. Outcomes of interest included rates of en bloc and complete polyp resection, risk of perforation and bleeding, and local recurrence. A network meta-analysis comparing all three approaches was conducted. In addition, a conventional comparative meta-analysis comparing UEMR to EMR was performed. Analysis was stratified according to polyp sizes (< 10 mm, ≥ 10 mm, and ≥ 20 mm). Results Twenty-two articles were included in this study. For polyps ≥ 10 mm, UEMR was inferior to ESD in achieving en bloc resection (P = 0.02). However, UEMR had shorter operating time for polyps ≥ 10 mm (P < 0.001), and ≥20 mm (P = 0.019) with reduced perforation risk for polyps ≥ 10 mm (P = 0.05) compared to ESD. In addition, en bloc resection rates were similar between UEMR and EMR, although UEMR had reduced recurrence for polyps ≥ 10 mm (P = 0.013) and ≥ 20 mm (P = 0.014). UEMR also had shorter mean operating than EMR for polyps ≥ 10 mm (P < 0.001) and ≥ 20 mm (P < 0.001). Risk of bleeding and perforation with UEMR and EMR were similar for polyp of all sizes. Conclusions UEMR has demonstrated technical and oncological outcomes comparable to ESD and EMR, along with a desirable safety profile. UEMR appears to be a safe and effective alternative to conventional methods for resection of polyps ≥ 10 mm.

Colorectal polypectomy and endoscopic mucosal resection: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2024

“…Results for en bloc and complete resection, and recurrence rates are mixed across trials, but UEMR appears comparable with CEMR. Regarding AEs, two subgroup analyses in meta-analyses for LNPCPs of any size reported comparable results between UEMR and CEMR [85,87]. In summary, UEMR has shown similar efficacy for resection, similar AE rates, and shorter procedure times when compared with CEMR for LNPCPs.…”

“…The other two RCTs, including lesions < 20 mm, reported similar outcomes [80,81]. One meta-analysis compared UEMR and CEMR for the removal of LNPCPs [82], and six meta-analyses reported UEMR and CEMR for LNPCPs in their subgroup analysis [83][84][85][86][87][88]. Results for en bloc and complete resection, and recurrence rates are mixed across trials, but UEMR appears comparable with CEMR.…”

Mucosectomía endoscópica bajo el agua: una técnica segura y efectiva entre la mucosectomía convencional y la disección submucosa

“…Actualmente, múltiples estudios observacionales y series de casos, sintetizados en meta-análisis, han descrito la factibilidad, seguridad y efectividad de la UEMR [9][10][11] . Yamashima et al realizaron un estudio clínico randomizado (RCT) multicéntrico en donde compararon la efectividad y seguridad de la UEMR con la CEMR en lesiones de 10-20 mm 12 , demostrando una mayor resección R0 (69% vs. 50%) y resección en bloque (89% vs. 75%), sin diferencias significativas en los tiempos de resección o complicaciones.…”

Underwater endoscopic submucosal dissection of a relapsing neoplastic colorectal lesion after surgery and radiotherapy: water to the rescue!

“…Histopathology confirmed R0 resection of a tubulovillous adenoma with low grade dysplasia. The safety and success of the underwater ESD technique have been recently reported [1][2][3]. During U-ESD, enhanced visualization of the submucosal space can be obtained due to the "buoyancy effect" [1,2].…”

“…The safety and success of the underwater ESD technique have been recently reported [1][2][3]. During U-ESD, enhanced visualization of the submucosal space can be obtained due to the "buoyancy effect" [1,2]. Furthermore, underwater resection may minimize thermal damage to the muscle layer, possibly decreasing the perforation rate [1,3].…”