Underwater Endoscopic Mucosal Resection Vs Conventional Endoscopic Mucosal Resection for Superficial Nonampullary Duodenal Epithelial Tumors in the Western Setting.

BACKGROUND & AIMS: Conventional endoscopic mucosal resection (C-EMR) is established as the primary treatment modality for superficial nonampullary duodenal epithelial tumors (SNADETs), but recently underwater endoscopic mucosal resection (U-EMR) has emerged as a potential alternative. The majority of previous studies focused on Asian populations and small lesions (≤20 mm). We aimed to compare the efficacy and outcomes of U-EMR vs C-EMR for SNADETs in a Western setting. METHODS: This was a retrospective multinational study from 10 European centers that performed both C-EMR and U-EMR between January 2013 and July 2023. The main outcomes were the technical success, procedure-related adverse events (AEs), and the residual/recurrent adenoma (RRA) rate, evaluated on a per-lesion basis. We assessed the association between the type of endoscopic mucosal resection and the occurrence of AEs or RRAs using mixed-effects logistic regression models (propensity scores). Sensitivity analyses were performed for lesions ≤20 mm or >20 mm. RESULTS: A total of 290 SNADETs submitted to endoscopic resection during the study period met the inclusion criteria and were analyzed (C-EMR: n = 201, 69.3%; U-EMR: n = 89, 30.7%). The overall technical success rate was 95.5% and comparable between groups. In logistic regression models, compared with U-EMR, C-EMR was associated with a significantly higher frequency of overall delayed AEs (odds ratio [OR], 4.95; 95% CI, 2.87-8.53), postprocedural bleeding (OR, 7.92; 95% CI, 3.95-15.89), and RRAs (OR, 3.66; 95% CI, 2.49-5.37). Sensitivity analyses confirmed these results when solely considering either small (≤20 mm) or large (>20 mm) lesions. CONCLUSIONS: Compared with C-EMR, U-EMR was associated with a lower rate of overall AEs and RRAs, regardless of lesion size. Our results confirm the possible role of U-EMR as an effective and safe technique in the management of SNADETs.

Successful Treatment of a Recurring Rectal Cloacogenic Polyp With Topical Steroids.

Cloacogenic polyps (CPs) are considered benign lesions arising in the anorectal transition zone. Most, but not all, patients are symptomatic with hematochezia, constipation, or abdominal pain. Although considered benign, resection is recommended due to the possibility of malignant transformation. In the case of recurrent disease, re-resection is usually hampered by scar tissue. We present the case of a 15-year-old male patient with a refractory CP, eventually successfully treated with topical steroids.

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

BACKGROUND & AIMS: Conventional endoscopic mucosal resection (CEMR) is the established method for the resection of non-pedunculated colorectal lesions (NPCRL) ≥ 10 mm. 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). METHODS: 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 ≥ 10 mm, 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. RESULTS: 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 ≥ 20 mm. R0 resection was higher in UEMR (OR: 1.72; 95% CI: 1.23-2.41). Other outcomes were not different between the 2 groups. CONCLUSIONS: UEMR is as safe as CEMR, with a higher overall R0 rate and a higher en bloc resection rate for lesions < 20 mm, leading to a lower overall recurrence rate. The results of this meta-analysis support the widespread use of UEMR.

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm.

BACKGROUND: The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations in current practice, such as endoscopic mucosal resection (EMR) and cold or hot snare polypectomy. Recently, EMR with circumferential precutting (EMR-P) has emerged as an effective technique, but the quality of current evidence in comparative studies of conventional EMR (CEMR) and EMR-P is limited. AIM: To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps. METHODS: This multicenter randomized controlled trial involved seven medical institutions in China. Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR. EMR-P was performed following submucosal injection, and a circumferential mucosa incision (precutting) was conducted using a snare tip. Primary outcomes included a comparison of the rates of en bloc and R0 resection, defined as one-piece resection and one-piece resection with histologically assessed clear margins, respectively. RESULTS: A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated. In the per-protocol analysis, the proportion of en bloc resections was 94.3% [95% confidence interval (CI): 88.2%-97.4%] in the EMR-P group and 86% (95%CI: 78.2%-91.3%) in the CEMR group (P = 0.041), while subgroup analysis showed that for lesions > 15 mm, EMR-P also resulted in a higher en bloc resection rate (92.0% vs 58.8% P = 0.029). The proportion of R0 resections was 81.1% (95%CI: 72.6%-87.4%) in the EMR-P group and 76.6% (95%CI: 68.8%-84.4%) in the CEMR group (P = 0.521). The EMR-P group showed a longer median procedure time (6.4 vs 3.0 min; P < 0.001). No significant difference was found in the proportion of patients with adverse events (EMR-P: 9.1%; CEMR: 6.4%; P = 0.449). CONCLUSION: In this study, EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm, particularly polyps > 15 mm in diameter, with higher R0 and en bloc resection rates and without increasing adverse events. However, EMR-P required a relatively longer procedure time than CEMR. Considering its potential benefits for en bloc and R0 resection, EMR-P may be a promising technique in colorectal polyp resection.

Issues and Prospects of Current Endoscopic Treatment Strategy for Superficial Non-Ampullary Duodenal Epithelial Tumors.

An increasing number of duodenal tumors are being diagnosed over the years, leading to increased confusion regarding the choice of treatment options. Small-to-large tumors and histological types vary from adenoma to carcinoma, and treatment methods may need to be selected according to lesion characteristics. Because of its anatomic characteristics, complications are more likely to occur in the duodenum than in other gastrointestinal organs. Several reports have described the outcomes of conventional endoscopic mucosal resection, endoscopic submucosal dissection, cold snare polypectomy, underwater endoscopic mucosal resection, endoscopic full-thickness resection, and laparoscopic and endoscopic cooperative surgery for duodenal tumors. However, even in the guidelines set out by various countries, only the treatment methods are listed, and no clear treatment strategies are provided. Although there are few reports with a sufficiently high level of evidence, considering the currently available treatment options is essential. In this report, we reviewed previous reports on each treatment strategy, discussed the current issues and prospects, and proposed the best possible treatment strategy.

Efficacy of Underwater Endoscopic Mucosal Resection for Nonpedunculated Colorectal Polyps: A Systematic Review and Meta-Analysis.

Recently, underwater endoscopic mucosal resection (UEMR) without submucosal injection was introduced as a new replacement for conventional EMR (CEMR) and was reported to be useful for resecting large colonic polyps. Here, we aimed to assess the efficacy and safety of these two methods by a systematic review and meta-analysis. We comprehensively searched multiple databases until July 2021 to identify randomized controlled trials (RCTs) comparing UEMR with CEMR. The primary outcomes were the proportion of R0 resection and mean procedure time, and the secondary outcomes were the proportion of en bloc resection and all adverse events. Three reviewers independently searched for articles, extracted data, and assessed the risk of bias. We evaluated the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach. This study was registered in www.protocols.io (Protocol Integer ID: 40849). We included six RCTs (1,374 polyps). We judged that a meta-analysis was not available, and the data were summarized narratively for the proportion of R0 resection. Regarding procedure time, UEMR likely resulted in a large reduction (mean difference = -64.3 seconds; 95% confidence interval (CI) = -122.5 to -6.0 seconds; I2 = 86%; moderate certainty of evidence). UEMR likely resulted in a large increase in en bloc resection (odds ratio = 1.85; 95% CI = 1.15 to 2.98; I2 = 60%; moderate certainty of evidence). Percentages of adverse events were 0-17% with CEMR and 0-16% with UEMR. In summary, UEMR might have higher efficacy than CEMR in the endoscopic resection of nonpedunculated colorectal polyps, with likely a large reduction in procedure time.

Avaliação de ressecção de mucosa endoscópica sob imersão d'água de pólipos colorretais em um centro ambulatorial no Brasil / Evaluation of underwater endoscopic mucosal resection for colorectal polyps in an outpatient clinic in brazil

ABSTRACT BACKGROUND: Since 2012, a new technique for resection of large polyps has been described, the underwater endoscopic mucosal resection (UEMR). Some advantages that emerge from it is the needless of injection in submucosal layer and a greater chance of complete capture of the polyp. OBJECTIVE: There are few studies of UEMR in Brazil. The aim of this study is to evaluate the safety and efficacy of this technique in one Brazilian center. METHODS: This case series was conducted from February to December of 2020. Colorectal polyps greater than 9 mm without features of deep submucosal invasion were resected using UEMR. RESULTS: Twenty-four large polyps were resected with the UEMR approach from 24 patients. The mean size of the polys was 19 mm, ranging from 12 to 35 mm. All lesions were successful resected and 66% (16/24) were resected en bloc. In histologic analyses, most of them were adenomas (70.8%) and only one had deep submucosal invasion. There were no cases of acute complications, such perforation or acute bleeding. CONCLUSION: The UEMR is a safe and feasible procedure. With the emerging data on the procedure, it seems to be a wonderful tool in preventing colorectal cancer and its applicability and scope should be encourage to surpass reference centers.

RESUMO CONTEXTO: Desde 2012, uma nova técnica para ressecção de pólipos grandes tem sido descrita, a ressecção da mucosa endoscópica sob imersão d'água (REMS). Algumas vantagens que surgem desta técnica são evitar a injeção na camada submucosa e a maior chance de captura completa do pólipo. Objetivo - Há poucos estudos com REMS no Brasil. Nosso objetivo é avaliar a segurança e a eficácia da técnica em um centro brasileiro. MÉTODOS: Esta série de casos foi conduzida de fevereiro a dezembro de 2020. Pólipos colorretais maiores que 9 mm sem sinais endoscópicos de invasão de submucosa foram ressecados utilizando RMES. RESULTADOS: Vinte e quatro pólipos foram ressecados com RMES em 24 pacientes diferentes. O tamanho médio dos pólipos era de 19 mm, variando de 12 a 35 mm. Todas as lesões foram ressecadas e 66% (16/24) foram ressecadas em monobloco. Na análise histológica, a maioria era adenoma (70.8%) e apenas uma havia invasão profunda da submucosa. CONCLUSÃO: O uso de REMS é um procedimento seguro e factível. Com o aumento de dados relativos ao procedimento, esta parece ser uma excelente ferramenta na prevenção do câncer colorretal e sua aplicabilidade deve ser encorajada para fora dos centros de referência.

Outcomes of Gastrointestinal Polyps Resected Using Underwater Endoscopic Mucosal Resection (UEMR) Compared to Conventional Endoscopic Mucosal Resection (CEMR).

Objective Underwater endoscopic mucosal resection (UEMR) is reported to be superior to conventional endoscopic mucosal resection (CMER) for the complete resection of large polyps and may offer increased procedural efficiency. Aims To compare recurrence rates and adverse events between UEMR and CEMR and define risk factors related to recurrence. Also, to assess recurrence rates in piecemeal endoscopic mucosal resection (EMR) based on the number of pieces resected. Methods We identified all patients with large polyps treated using the UEMR technique at Carilion Clinic, Roanoke, VA, USA between January 1, 2014 and December 31, 2017 with follow-up through October of 2018. We matched the UEMR patients with patients treated using the CEMR technique (1:2 matching, respectively). The Kaplan-Meier curve was used to estimate the cumulative risks of polyp recurrence. The Cox proportional hazard analysis was used to assess risk factors for developing polyp recurrence. Results Sixty-eight patients (mean age: 63.4 ± 12.5 years; 52.9% males) with polyps removed using the UEMR technique (Group 1) were matched with 122 patients (mean age: 64.4 ± 10.0 years; 51.6% males) who had polyps removed using CEMR (Group 2). Polyps resected in fewer pieces (≤ 3) had lower recurrence rates compared to the ones resected in >3 pieces. Right colon polyps removed using UEMR had a lower recurrence rate compared to right colon polyps resected using CEMR. Polyp size and a high degree of dysplasia were associated with a high risk of polyp recurrence after resection. Completing advanced endoscopy training was also associated with a lower risk of recurrence. Conclusion UEMR had a lower recurrence rate compared with CEMR for right colon polyps. Factors associated with recurrence included the degree of training, high-grade dysplasia, and polyp size.

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

BACKGROUND: Underwater 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. AIM: To evaluate the effectiveness and safety of UEMR in the treatment of colorectal polyps. METHODS: Clinical 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. RESULTS: Seven 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). CONCLUSION: UEMR is an effective technique for colorectal polyps and appears to have some advantages over EMR, particularly with regard to some treatment outcomes.

Underwater versus conventional endoscopic mucosal resection for small size non-pedunculated colorectal polyps: a randomized controlled trial : (UEMR vs. CEMR for small size non-pedunculated colorectal polyps).

BACKGROUND: Underwater endoscopic mucosal resection (UEMR) is a recently developed technique and can be performed during water-aided or ordinary colonoscopy for the treatment of colorectal polyps. The objective of this clinical trial was to evaluate the efficacy and safety of UEMR in comparison with conventional endoscopic mucosal resection (CEMR) of small non-pedunculated colorectal polyps. METHODS: Patients with small size, non-pedunculated colorectal polyps (4-9 mm in size) who underwent colonoscopic polypectomy were enrolled in this multicenter randomized controlled clinical trial. The patients were randomly allocated to two groups, an UEMR group and a CEMR group. Efficacy and safety were compared between groups. RESULTS: In the intention-to-treat (ITT) analysis, the complete resection rate was 83.1% (59/71) in the UEMR group and 87.3% (62/71) in the CEMR group. The en-bloc resection rate was 94.4% (67/71) in the UEMR group and 91.5% (65/71) in the CEMR group (difference 2.9%; 90% CI - 4.2 to 9.9%), showed noninferiority (noninferiority margin - 5.7% < - 4.2%). No significant difference in procedure time (81 s vs. 72 s, P = 0.183) was observed. Early bleeding was observed in 1.4% of patients in the CEMR group (1/71) and 1.4% of patients in the UEMR group (1/71). None of the patients in the UEMR group complained of postprocedural bloody stool, whereas two patients in the CEMR group (2/64) reported this adverse event. CONCLUSION: Our results indicate that UEMR is safer and just as effective as CEMR in En-bloc resection for the treatment of small colorectal polyps as such, UEMR is recommended as an alternative approach to excising small and non-pedunculated colorectal adenomatous polyps. TRIAL REGISTRATION: Clinical Trials.gov, NCT03833492 . Retrospectively registered on February 7, 2019.

Feasibility study comparing underwater endoscopic mucosal resection and conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumor < 20 mm.

BACKGROUND AND AIM: Underwater endoscopic mucosal resection (UEMR) has been reported as an alternative to conventional EMR for superficial non-ampullary duodenal epithelial tumors (SNADET). However, the detailed outcomes are unclear. This study aimed to compare the clinical outcomes between UEMR and EMR for SNADET <20 mm. PATIENTS AND METHODS: This is a retrospective observational study using a prospective maintained database. From November 2017 to December 2018, 104 consecutive cases of attempted UEMR for SNADET <20 mm were prospectively allocated. A total of 240 cases of attempted EMR were chosen as historical controls. We compared technical success rate, defined as the resection rate without conversion to ESD; en bloc resection rate; R0 resection rate; and adverse event rate. Next, multivariate analyses were constructed to identify predictors of conversion to ESD, piecemeal resection, and RX or R1 (RX/R1) resection. RESULTS: Technical success rate of UEMR was significantly higher than that of EMR (87% and 70%, P < 0.01). En bloc resection and R0 resection rates of UEMR were significantly lower than those of EMR (en bloc resection: 87% vs 96%, P < 0.01; R0 resection: 67% vs 80%, P = 0.05). Concerning adverse events, there were no significant differences. In multivariate analyses, attempted EMR, lesion size and depressed type were independent predictors of conversion to ESD. Attempted UEMR was an independent predictor of piecemeal resection and RX/R1 resection. CONCLUSION: The present study indicated that UEMR could be a feasible endoscopic resection method for SNADET (UMIN000025442).