Safety Of Underwater Endoscopic Mucosal Resection Research Articles

Feasibility and Efficacy of Gastric Underwater Endoscopic Mucosal Resection.

Gastric cancer, a leading cause of cancer-related deaths globally, necessitates effective and early detection and treatment strategies. Endoscopic resection techniques, particularly endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), have evolved significantly, enhancing the treatment of gastric neoplasms. Underwater endoscopic mucosal resection (UEMR) is a widely used technique for the resection of duodenal and colorectal neoplasms. However, the feasibility and efficacy of UEMR in the stomach are not well established. This retrospective observational study, conducted at a tertiary medical center, evaluated the efficacy and safety of UEMR in 81 patients with gastric neoplasms. Thus, it indicates that UEMR is a highly effective and safe technique for managing small to medium-sized gastric neoplasms, achieving 100% en bloc and 93.8% R0 resection rates with a low incidence of complications. Moreover, the procedure time was found to be significantly shorter for UEMR compared to ESD, thus highlighting its efficiency. While UEMR demonstrates high safety and efficacy, it is not suitable for all patients, with some requiring conversion to ESD as a treatment option. Despite the promising results, broader validation through extensive and randomized trials is recommended to establish UEMR as a standard approach in gastric cancer management.

Underwater versus conventional endoscopic mucosal resection for colorectal lesions: a systematic review and meta-analysis of randomized clinical trials.

Conventional endoscopic mucosal resection (CEMR) is the established method for the resection of non-pedunculated colorectal lesions (NPCRL) ≥ 10mm. In the last decade, underwater endoscopic mucosal resection (UEMR) has been introduced as a potential alternative. The aim of this systematic review with meta-analysis is to compare the recurrence and safety of UEMR and CEMR by analyzing only randomized controlled trials (RCTs). We systematically searched PubMed, Cochrane Library and EMBASE until April 2023. Studies met the following inclusion criteria: (1) RCTs, (2) comparing UEMR with CEMR, (3) NPCRL ≥ 10mm, and (4) reporting the outcomes of interest. Primary outcomes were recurrence and safety. Secondary outcomes were en bloc, R0, complete resection, clipping and adverse events per type. Five RCTs were included. UEMR was associated with a lower recurrence rate (OR: 0.56; 95% CI: 0.32-0.97). Thus, the RR of recurrence was 1.7 times higher in the CEMR group (95% CI, 1.04-2.77). There was no significant difference in the pooled safety analysis. UEMR showed better en bloc resection rates (OR: 1.54; 95% CI: 1.15-2.07), but subgroup analysis showed comparable rates in lesions ≥ 20mm. R0 resection was higher in UEMR (OR: 1.72; 95% CI: 1.23-2.41). Other outcomes were not different between the 2 groups. UEMR is as safe as CEMR, with a higher overall R0 rate and a higher en bloc resection rate for lesions < 20mm, leading to a lower overall recurrence rate. The results of this meta-analysis support the widespread use of UEMR.

Underwater Versus Conventional Endoscopic Mucosal Resection for Superficial Non-ampullary Duodenal Epithelial Tumors: A Systematic Review and Meta-Analysis.

Duodenal underwater endoscopic mucosal resection (UEMR) has been suggested as a feasible treatment option for superficial non-ampullary duodenal epithelial tumors (SNADETs). However, its efficacy and safety have not been fully established yet. Thus, the objective of this systematic review and meta-analysis was to determine the efficacy and safety of UEMR as compared with conventional endoscopic mucosal resection (CEMR) in the treatment of SNADETs. We conducted a comprehensive literature search in PubMed, EMBASE, the Cochrane Library. Studies comparing CEMR and UEMR for the resection of SNADET were included. Outcomes included en-bloc and complete resection rates, adverse events, and procedure time. A total of six studies with 2454 lesions were included in the quantitative synthesis. En-bloc and complete resection rates were not significantly different between UEMR and CEMR (OR for en-bloc resection: 0.997 [95% CI 0.439-2.266]; OR for complete resection: 0.960 [95% CI 0.628-1.468]). There was no significant risk difference for perforation (risk difference: - 0.002; 95% CI - 0.009 to 0.005) or delayed bleeding (risk difference: - 0.001; 95% CI - 0.014 to 0.011). Procedure time was significantly shorter in the UEMR (standardized mean difference: - 1.294; 95% CI - 2.461 to - 0.127). The risk of recurrence was not significantly different between UEMR and CEMR (risk difference: 0.001; 95% CI - 0.041 to 0.044). Although our results did not show any superiority of UEMR over CEMR in the treatment of SNADETs, UEMR showed equivalent efficacy and safety as compared with CEMR and was associated with a shorter procedure time.

Underwater endoscopic mucosal resection for colorectal lesions: Can it be an "Underwater" revolution?

Underwater endoscopic mucosal resection (UEMR) is a newly developed technique for the removal of colorectal, duodenal, esophageal, gastric, ampullary, and small intestinal lesions. We performed a PubMed literature search for articles reporting UEMR outcomes for colorectal polyps. Four randomized controlled trials, nine non‐randomized prospective trials, 16 retrospective studies, and 27 case reports were selected for assessment of the efficacy and safety of UEMR. We summarized the therapeutic outcomes of UEMR in each category according to the lesion characteristics [small size (<10 mm), intermediate size (10–19 mm), large size (≥20 mm), recurrent lesion, and rectal neuroendocrine tumor], and calculated the incidence of adverse events among the included articles. As the treatment outcomes for small polyps appeared similar between UEMR and conventional endoscopic mucosal resection (CEMR), UEMR can be a standard procedure for small colorectal polyps suspicious for high‐grade dysplasia to avoid incomplete removal of occult invasive cancer by cold snare polypectomy. As UEMR showed satisfactory outcomes for intermediate‐size lesions and recurrent lesions after endoscopic resection, UEMR can be a standard procedure for these lesions. Regarding large lesions and rectal neuroendocrine tumors, comparisons of UEMR with current standard methods for them were lacking, and further investigations are warranted. Adverse events appeared comparable or less frequent for UEMR compared with CEMR but still existed. Therefore, careful implementation of this new technique in clinical practice is important for its widespread use.

Underwater vs conventional endoscopic mucosal resection in treatment of colorectal polyps: A meta-analysis.

BACKGROUNDUnderwater endoscopic mucosal resection (UEMR) of colorectal lesions is emerging as an alternative method to conventional endoscopic mucosal resection (EMR); however, it is still controversial whether there is a difference in the effectiveness between UEMR and EMR.AIMTo evaluate the effectiveness and safety of UEMR in the treatment of colorectal polyps.METHODSClinical studies comparing the effectiveness or safety of UEMR in the treatment of colorectal polyps were searched in medical databases, including PubMed, Embase, Cochrane Library, CNKI, and Wanfang Data, monographs, theses, and papers presented at conferences. Statistical analyses were performed using Revman 5.3 software.RESULTSSeven non-randomized controlled trials and one randomized controlled trial met the inclusion criteria. In total, 1382 patients (1511 polyps) were included in the study, including 722 who received UEMR and 789 who received EMR. In the UEMR and EMR groups, the en bloc resection rates were 85.87% and 73.89%, respectively, with a relative risk (RR) value of 1.14 (95% confidence interval [CI]: 1.01-1.30; P < 0.05). In the sub-group analysis, the en bloc resection rate showed no statistically significant difference between the EMR and UEMR groups for polyps less than 20 mm in diameter. However, a statistically significant difference was found between the EMR and UEMR groups for polyps equal to or greater than 20 mm in diameter. The post-endoscopic resection recurrence rates at 3-6 mo of the UEMR and EMR groups were 3.26% and 15.17%, respectively, with an RR value of 0.27 (95%CI: 0.09-0.83; P < 0.05). The post-endoscopic resection recurrence rates of UEMR and EMR at 12 mo were 6.25% and 14.40%, respectively, with an RR value of 0.43 (95%CI: 0.20-0.92; P < 0.05). Additionally, the incidence of adverse events was 8.17% and 6.21%, respectively, with an RR value of 1.07 (95%CI: 0.50-2.30; P > 0.05).CONCLUSIONUEMR is an effective technique for colorectal polyps and appears to have some advantages over EMR, particularly with regard to some treatment outcomes.

S0139 Underwater vs Conventional Endoscopic Mucosal Resection for Colorectal Lesions: A Systematic Review and Meta-Analysis

INTRODUCTION: Underwater endoscopic mucosal resection (UEMR) for colorectal polyps has been reported to have good outcomes in recent studies. We conducted a systematic review and meta-analysis studying efficacy and safety of UEMR as compared to conventional EMR (CEMR). METHODS: A comprehensive search of multiple databases (through May 2020) was performed to identify studies that reported outcome of UEMR and CEMR for colorectal lesions. Odds ratio was calculated for outcomes comparing CEMR and UEMR. Outcomes assessed included adverse events, intra-procedural bleeding, delayed bleeding, perforation, post-polypectomy syndrome, incomplete resection, en bloc resection, R0 resection and rate of recurrence amongst UEMR and CEMR. Subgroup analysis was performed for non-pedunculated polyps ≥10 mm and ≥20 mm. All analysis was performed using RevMan 5.0 (Cochrane Collaboration). RESULTS: A total of 1,651 patients with 1,704 polyps were included from 9 studies. The mean age and polyp size ranged from 62.3 to 70 years and 9.9 mm to 30.2 mm, respectively. 66.4% of patients were males. Adverse events were 91 (10.2%) in CEMR group and 59 (7.2%) in UEMR group. Compared to CEMR, overall complications (odds ratio [OR]: 0.61 (95% CI, 0.42–0.88) (P = 0.009), and intra-procedural bleeding (OR: 0.54, 95% CI, 0.36–0.81, P = 0.003) was significantly lower with UEMR (Figure 1a and 1b). There was also a significantly lower rate of incomplete resection (OR: 0.19 (95% CI, 0.05–0.78, P = 0.02) and polyp recurrence (OR: 0.41, 95% CI, 0.24–0.72, P = 0.002) after UEMR (Figure 2a and 2b). Odds of R0 resection were significantly higher in UEMR as compared to CEMR with OR of 2.20 (95% CI, 1.26–3.83, I2 = 0, P = 0.0005) (Figure 2c). There were 1,204 polyps ≥10 mm (612 CEMR and 592 UEMR), and 294 polyps (166 CEMR and 128 UEMR) were ≥ 20 mm. The recurrence rate was lower for non-pedunculated polyps ≥10 mm (OR 0.24, 95% CI, 0.10–0.57, P = 0.001) and ≥20 mm (OR 0.14, 95% CI, 0.02–0.72, P = 0.01). The rate of en bloc resection, delayed bleeding, perforation and post-polypectomy syndrome were similar in both groups (P > 0.05). All results along with subgroup analysis are summarized in Table 1. CONCLUSION: In this systematic review and meta-analysis, we found that UEMR is safer and more effective than CEMR with lower rates of adverse events and recurrence. UEMR use should be encouraged over CEMR.Figure 1.: Forest plot showing odds ration of any complication (A) and intra-procedural bleeding (B) comparing conventional endoscopic mucosal resection and underwater endoscopic mucosal resection.Figure 2.: Forest plot showing odds ratio of incomplete resection (A), R0 resection (B) and recurrence (C) comparing conventional endoscopic mucosal resection and underwater endoscopic mucosal resection.Table 1.: All Results along with subgroup analysis of non-pedunculated polyps ≥ 10 mm and ≥20 mm comparing underwater and conventional endoscopic mucosal resection

Underwater endoscopic mucosal resection of colorectal neoplasia is easily learned, efficacious, and safe

Underwater endoscopic mucosal resection (UEMR) without submucosal injection is a novel endoscopic procedure. It is not known if UEMR can be easily taught and learned, and the efficacy and safety of UEMR has not been demonstrated at multiple medical centers. Our aims were to demonstrate that (1) UEMR is a technique that can be easily learned by an endoscopist trained in traditional EMR, (2) endoscopic ultrasound (EUS) may not be required before UEMR, and (3) UEMR is an efficacious and safe method for resection of large or flat neoplastic colorectal lesions. An experienced interventional endoscopist began performing UEMR after observing UEMR procedures. Colorectal UEMR was performed using a pediatric colonoscope with a cap, a waterjet, and a ‘duck-bill’ snare using blended current. Submucosal injection was not used. Patient data were collected prospectively. A total of 21 patients (17 men, mean age 64.9 years, range 51-83) referred for polypectomy of large colorectal lesions underwent UEMR. A total of 43 colorectal lesions with a mean size of 20 mm (range 8-50) were resected by UEMR. Lesions were found in the right colon (N = 16), transverse colon (N = 5), left colon (N = 19), and rectum (N = 3). Pathology demonstrated tubular adenoma (N = 29), tubulovillous adenoma (N = 5), high-grade dysplasia (N = 3), serrated sessile adenoma without dysplasia (N = 3), and non-neoplastic tissue (N = 3). EUS was used in only two cases of rectal neoplasia (4.7 %). Of the UEMRs, 97.7 % were successful with complete resection of colorectal polyps. The only adverse event was one case (2.3 %) of delayed post-UEMR bleeding. UEMR was easily learned by an endoscopist already skilled in conventional EMR. EUS may not be required prior to most UEMR procedures. UEMR appears to be an efficacious and safe alternative to traditional EMR or ESD for large or flat colorectal neoplasms.