Efficacy of Underwater Endoscopic Mucosal Resection for Superficial Non-Ampullary Duodenal Epithelial Tumor

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.

Can underwater endoscopic mucosal resection be an alternative to conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumors?

Objectives

Underwater endoscopic mucosal resection (UEMR) is a simpler procedure for superficial non-ampullary duodenal epithelial tumors (SNADET) than conventional endoscopic mucosal resection (cEMR). This study aimed to evaluate whether cEMR can be substituted by UEMR for SNADET in terms of effectiveness, safety, and learning curve.

Methods

A total of 157 consecutive patients with 203 SNADETs ≤20 mm in diameter, including 107 lesions resected by cEMR and 96 lesions resected by UEMR, between January 2019 and May 2023, were retrospectively recruited. The treatment outcomes were compared between the cEMR and UEMR groups. The risk factors for incomplete resection by UEMR were analyzed using univariate and multivariate analyses. Lesions in the UEMR group were divided chronologically into five periods; thereafter, the en bloc resection rate and procedure time were compared.

Results

No significant differences existed between the cEMR and UEMR groups in the mean procedure time (3.9 min vs. 3.6 min, p = 0.1380) or en bloc resection rate (91% vs. 94%, p = 0.4138). No perforation was observed in either group. Tumor size was an independent risk factor for incomplete resection using UEMR (p < 0.01). The history of biopsy was not associated with incomplete resection using UEMR. The en bloc resection rate of UEMR was 100% (20/20) in the first period and ranged from 90% to 100% over all periods.

Conclusion

UEMR is safe and effective for SNADET ≤20 mm, regardless of a history of biopsy, and is easy to learn. Thus, UEMR can serve as an alternative to cEMR.

Conventional versus underwater endoscopic resection for superficial non-ampullary duodenal epithelial tumours

BACKGROUND AND OBJECTIVE

Several endoscopic resection methods have been developed as less invasive treatments for superficial non-ampullary duodenal epithelial tumours. This study aimed to compare outcomes of conventional endoscopic mucosal resection and underwater endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours, including resection depth and rate of the muscularis mucosa contained under the lesion.

METHODS

This single-centre retrospective cohort study conducted from January 2009 to December 2021 enrolled patients who underwent conventional endoscopic mucosal resection and underwater endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours and investigated their clinicopathological outcomes using propensity score matching.

RESULTS

Of the 285 superficial non-ampullary duodenal epithelial tumours, 98 conventional endoscopic mucosal resections and 187 underwater endoscopic mucosal resections were included. After propensity score matching, 64 conventional endoscopic mucosal resections and 64 underwater endoscopic mucosal resections were analysed. The R0 resection rate was significantly higher in underwater endoscopic mucosal resection cases than in conventional endoscopic mucosal resection cases (70.3% vs. 50.0%; P = 0.030). In the multivariate analysis, a lesion diameter > 10 mm (odds ratio 7.246; P = 0.001), being in the 1st-50th treatment period (odds ratio 3.405; P = 0.008), and undergoing conventional endoscopic mucosal resection (odds ratio 3.617; P = 0.016) were associated with RX/R1 resection. Furthermore, in underwater endoscopic mucosal resection cases, the R0 rate was significantly higher for lesions diameter ≤10 mm than >10 mm, and was significantly higher in the 51st-treatment period than in the 1st-50th period. Conventional endoscopic mucosal resection and underwater endoscopic mucosal resection cases showed no significant difference in resection depth and muscularis mucosa containing rate.

CONCLUSIONS

Underwater endoscopic mucosal resection may be more acceptable than conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours ≤ 10 mm. A steep early learning curve may be acquired for underwater endoscopic mucosal resection. Large multicentre prospective studies need to be conducted to confirm the effectiveness of underwater endoscopic mucosal resection.

Underwater Endoscopic Mucosal Resection Versus Conventional Endoscopic Mucosal Resection for Superficial Non-ampullary Duodenal Epithelial Tumors ≤20 mm: A Systematic Review With Meta-analysis

BACKGROUND

Underwater endoscopic mucosal resection (UEMR) is increasingly applied in the treatment of superficial non-ampullary duodenal epithelial tumors (SNADETs). This meta-analysis aimed to assess the efficacy and safety of UEMR for SNADETs ≤20 mm in comparison with conventional endoscopic mucosal resection (CEMR).

METHODS

The following electronic databases were searched from 2012 until November 20, 2021: PubMed, Embase, Scopus, Web of Science databases, and Cochrane Library. The primary outcomes were the rates of en bloc resection and complete (R0) resection, and the secondary outcomes were procedure time, adverse events (delayed bleeding and delayed perforation), and recurrence rate.

RESULTS

A total of 6 studies with 679 lesions (331 underwent UEMR and 348 CEMR) were included in this study. The pooled analysis showed that UMER achieves a similar en bloc resection rate (87.6 vs. 89.9%; odds ratio [OR], 1.29; 95% confidence interval [CI], 0.45 to 3.73; P =0.64; I2 =74%), a similar R0 resection rate (67.3 vs. 73.6%; OR, 1.11; 95% CI, 0.55 to 2.23; P =0.78; I2 =59%), a shorter procedure time (min) (mean difference [MD], -4.05, 95% CI: -6.40 to -1.71; P =0.0007; I2 =70%) compared with CEMR. There were no significant differences in the rates of delayed bleeding, delayed perforation, and recurrence (2.4 vs. 1.7%, 0 vs. 0.6%, 2.2 vs. 4.4%, respectively).

CONCLUSION

This meta-analysis demonstrated that UEMR appears to be an effective and safe alternative to CEMR for SNADETs ≤20 mm.

Underwater versus conventional EMR for nonpedunculated colorectal lesions: a randomized clinical trial

BACKGROUND AND AIMS

Conventional endoscopic mucosal resection (CEMR) is the standard modality for removing nonpedunculated colorectal lesions. Underwater endoscopic mucosal resection (UEMR) has emerged as an alternative method. There are few comparative studies between these techniques, especially evaluating recurrence. Therefore, the purpose of this trial was to compare CEMR and UEMR for the resection of colorectal lesions with respect to efficacy, safety, and recurrence rate.

METHODS

This was a randomized controlled trial of UEMR versus CEMR for naïve and nonpedunculated lesions measuring between 10 and 40 mm. The primary outcome was adenoma recurrence at 6 months after the resection. Secondary outcomes were rates of technical success, en bloc resection, and adverse events. Block randomization was used to assign patients. Tattooing was performed to facilitate localization of the scars and eventual recurrences. Endoscopic follow-up was scheduled at 6 months after the procedure. The sites of resections were examined with white-light imaging, narrow-band imaging (NBI), and conventional chromoscopy with indigo carmine followed by biopsies.

RESULTS

One hundred five patients with 120 lesions were included, with a mean size of 17.5 ± 7.1 (SD) mm. Sixty-one lesions were resected by UEMR and 59 by CEMR. The groups were similar at baseline regarding age, sex, average size, and histologic type. Lesions in the proximal colon in the CEMR group corresponded to 83% and in the UEMR group to 67.8% (P = .073). There was no difference between groups regarding success rate (1 failure in each group) and en bloc resection rate (60.6% UEMR vs 54.2% CEMR, P = .48). Intraprocedural bleeding was observed in 5 CEMRs (8.5%) and 2 UEMRs (3.3%) (P = .27). There was no perforation or delayed hemorrhage in either groups. Recurrence rate was higher in the CEMR arm (15%) than in the UEMR arm (2%) (P = .031). Therefore, the relative risk of 6-month recurrence rate in the CEMR group was 7.5-fold higher (95% CI, 0.98-58.20), with a number needed to treat of 7.7 (95% CI, 40.33-4.22). The higher recurrence rate in the CEMR group persisted only for lesions measuring 21 to 40 mm (35.7% vs 0%; P = .04).

CONCLUSION

This study demonstrated that UEMR was associated with a lower adenoma recurrence rate than was CEMR. Both endoscopic techniques were effective and had similar rates of adverse events for the treatment of nonpedunculated colorectal lesions.

Efficacy and safety of underwater endoscopic mucosal resection for ≤20 mm superficial non-ampullary duodenal epithelial tumors: Systematic review and meta-analysis

Background and aims

Superficial non-ampullary duodenal epithelial tumors (SNADETs) as a rare disease have gradually increased in recent years. Underwater endoscopic mucosal resection (UEMR) has emerged as a newly available option for the endoscopic resection of SNADETs. This study aimed to evaluate the efficacy and safety of UEMR for ≤20 mm SNADETs.

Methods

A literature search was performed across multiple databases, including PubMed, Embase, Scopus, and Clinical trials for studies containing tumors ≤20 mm published from January 1, 2012, to August 8, 2022. Outcomes examined were the pooled rates of en bloc resection, R0 resection, adverse events, and recurrence. Subgroup analyses of the resection rate were conducted stratified by sample size and polyp size.

Results

A total of 10 studies with UEMR performed in a total of 648 tumors were included for analysis. The pooled rate of en bloc resection and R0 resection was 88.2% (95% confidence interval (CI): 82.1-93.2) and 69.1% (95% CI: 62.2-76.1), respectively. The results showed pooled rate of intraoperative bleeding rate was 2.9% (95% CI: 0-9.0), delayed bleeding rate was 0.9% (95% CI: 0.1-2), recurrence rate was 1.5% (95% CI: 0-4.9). In the subgroup analysis, R0 and en-bloc resection rates were significantly higher in <10 mm than 10-20 mm SNADETs subgroups (R0 resection rate 83.1 vs. 48.6%; en bloc resection rate 100.0 vs. 84.0%, P < 0.05).

Conclusion

Underwater endoscopic mucosal resection was an effective and safe technique for the optional treatment for ≤20 mm SNADETs, especially of <10 mm.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022340578.

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

BACKGROUND/AIMS

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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

A feasibility study comparing gel immersion endoscopic resection and underwater endoscopic mucosal resection for superficial nonampullary duodenal epithelial tumors

BACKGROUND

Although gel immersion endoscopic resection (GIER) is a potential alternative to underwater endoscopic mucosal resection (UEMR) for superficial nonampullary duodenal epithelial tumors (SNADETs), comparisons between the two are currently insufficient.

METHODS

40 consecutive procedures performed in 35 patients were retrospectively reviewed; the primary outcome was procedure time, and the secondary outcomes were en bloc and R0 resection rates, tumor and specimen size, and adverse events.

RESULTS

Lesions were divided into GIER (n = 22) and UEMR groups (n = 18). The median (range) procedure time was significantly shorter in the GIER group than in the UEMR group (2.75 [1-3.5] minutes vs. 3 2 3 4 5 6 7 8 9 10 minutes; P = 0.01). The en bloc resection rate was 100 % in the GIER group, but only 83.3 % in the UEMR group. The R0 resection rate was significantly higher in the GIER group than in the UEMR group (95.5 % vs. 66.7 %; P = 0.03). The median specimen size was larger in the GIER group than in the UEMR group (14 mm vs. 7.5 mm; P < 0.001). The tumor size was not significantly different between the groups and no adverse events were observed.

CONCLUSIONS

GIER is efficacious and safe to treat SNADETs, although additional studies are needed.

Underwater versus conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumors ≤20mm: A systematic review and meta-analysis

BACKGROUND AND AIMS

Underwater endoscopic mucosal resection (UEMR) is an emerging technique for endoscopic resection of superficial non-ampullary duodenal epithelial tumors (SNADETs). However, compared to conventional EMR, its efficacy and safety has not been widely explored.

METHODS

We conducted a comprehensive search using the Pubmed, Embase, and Cochrane Library databases to identify studies comparing the efficacy and safety of UEMR versus EMR for SNADETs. The main outcomes examined included en bloc resection rate, R0 resection rate, recurrence rate, procedure time, and adverse events.

RESULTS

A total of 5 studies comprising 635 patients were included. All the literature included duodenal lesions smaller than 20 mm. The pooled analysis showed that UEMR could achieve a higher en bloc resection rate (OR 1.78, 95%CI: 1.17 to 2.71, P = 0.007) and shorter procedure time (MD -4.08, 95%CI: -6.44 to -1.73, P = 0.0007) than EMR. However, the pooled results did not support a superiority of UEMR over EMR for R0 resection rate (OR 1.27; 95% CI: 0.90 to 1.81, P = 0.18) or recurrence rate (OR 0.49; 95% CI: 0.15 to 1.67, P = 0.26). The occurrence of adverse events, including postoperative bleeding, intraoperative perforation, and delayed perforation, was very low in included studies.

CONCLUSION

Compared to EMR, UEMR is an effective and safe technique for SNADETs ≤20 mm.

Appropriate selection of endoscopic resection for superficial nonampullary duodenal adenomas in association with recurrence

BACKGROUND AND AIMS

The appropriate selection of endoscopic resection for relatively small superficial nonampullary duodenal adenomas (SNADAs) considering recurrence is not completely clarified. Therefore, this study investigated endoscopic resection utility (EMR, underwater EMR [UEMR], and cap-assisted EMR [EMRC]) for SNADAs from the viewpoint of recurrence and short-term outcomes.

METHODS

We retrospectively analyzed patients with sporadic SNADAs who underwent EMR, UEMR, and EMRC at Chiba University Hospital between May 2004 and March 2020 and were observed for ≥12 months after endoscopic resection (EMR, 34 patients, 36 lesions; UEMR, 54 patients, 55 lesions; and EMRC, 45 patients, 48 lesions). Outcomes were evaluated using weighted logistic regression analysis. The logistic regression analysis was weighted using propensity scores.

RESULTS

EMRC showed significantly higher en-bloc and R0 resection rates than EMR. All techniques were equally safe. Only 1 case each of intraoperative perforation and postoperative perforation (in 2 different patients) occurred, which were associated with EMRC. UEMR resulted in higher R0 resection and lower postbleeding rates than EMR. Moreover, patients who underwent UEMR showed no perforation. Median observation period per lesion after endoscopic resection was 84 months (range, 16-199) for patients who underwent EMR, 25 months (range, 12-60) for patients who underwent UEMR, and 63 months (range, 12-180) for patients who underwent EMRC. No significant difference was observed between EMR versus UEMR and between EMR versus EMRC in terms of recurrence (odds ratio, .20 [95% confidence interval, .01-2.86; P = .24] and .78 [95% confidence interval, .09-6.84; P = .82], respectively).

CONCLUSIONS

Recurrence risk was not different for EMR, UEMR, and EMRC. Therefore, UEMR, a simple and safe procedure, could be the first choice for relatively small SNADAs. With larger prospective studies, UEMR data may turn out to be more robust, corroborating it as the endoscopic modality of choice for certain SNADAs.

Endoscopic resection of superficial non‐ampullary duodenal epithelial tumor

Although superficial non‐ampullary duodenal epithelial tumor (SNADET) was previously considered a rare disease, in recent years, the opportunities to detect and treat SNADET are increasing. Considering the high morbidity of pancreatoduodenectomy, endoscopic resection can be a treatment option that preserves the organs and contributes maintain patients’ quality of life. Endoscopic mucosal resection (EMR) is a standard treatment for relatively small lesions in gastrointestinal tracts, however, it is difficult because submucosal fibrosis frequently occurs due to the previous biopsy. Recently, some modified EMR techniques including underwater EMR (UEMR) and cold polypectomy (CP) have been proposed. In UEMR, the duodenal lumen is filled with water or saline and resected the targe lesion with a snare without injection into the submucosa. It would be a treatment option that could reduce candidates for ESD especially SNADET less than 20 mm. CP was reported as a safe and convenient means for SNADET. It would also be one of the standard treatments for diminutive lesions, though there remain some concerns on its resectability. ESD for SNADET is technically challenging, especially with an extremely high risk of adverse event (AE) with a reported bleeding rate of more than 20% and perforation rate up to about 40%. However, modified treatment techniques including the water pressure method and pocket creation method have been reported to potentially contribute to improving outcomes of ESD. Moreover, accumulated evidence shows closing the mucosal defect significantly reduces delayed adverse events after duodenal endoscopic treatments. Further studies are warranted to elucidate curative criteria, long‐term outcomes, and appropriate surveillance strategy.

Utility of underwater EMR for nonpolypoid superficial nonampullary duodenal epithelial tumors ≤20 mm

BACKGROUND AND AIMS

The application of underwater EMR (UEMR) for nonpolypoid superficial nonampullary duodenal epithelial tumors (SNADETs) has not been comprehensively assessed. Therefore, the current study aimed to validate the efficacy of UEMR versus conventional EMR and cap-assisted EMR (EMRC) for SNADETs measuring ≤20 mm.

METHODS

We retrospectively analyzed patients with sporadic nonpolypoid SNADETs measuring ≤20 mm undergoing EMR, EMRC, or UEMR at Chiba University Hospital between May 2004 and October 2020 (EMR, 21 patients and 23 SNADETs; UEMR, 60 patients and 61 SNADETs; EMRC, 45 patients and 48 SNADETs). A weighted logistic regression analysis was performed to analyze outcomes. Univariate and multivariate logistic regression models were used to identify the predictors of RX/1 and piecemeal resection. The recurrence rate of lesions observed ≥12 months after resection was assessed.

RESULTS

Both UEMR and EMRC had a significantly higher R0 resection rate than EMR. UEMR had significantly lower multiple resection and postbleeding rates than EMR. Only 1 patient (2.1%) who underwent EMRC experienced intraoperative and postoperative perforation. EMR was involved in RX/1 and piecemeal resection. The recurrence rates of EMR, UEMR, and EMRC were 4.3%, 2.0%, and 6.3%, respectively.

CONCLUSIONS

UEMR had significantly higher R0 resection and lower postbleeding rates than EMR. Moreover, it was safer than EMRC and was associated with a lower incidence of recurrences. The significant results of the retrospective analysis suggest a randomized controlled study with adequate numbers needs to be conducted to confirm the superior efficacy of UEMR before it is recommended for primary treatment option for SNADETs measuring ≤20 mm.

Resectability of underwater endoscopic mucosal resection for duodenal tumor: A single-center, retrospective pilot study

BACKGROUND AND AIM

Underwater endoscopic mucosal resection (U-EMR) has been attracting much attention as treatment for patients with nonampullary duodenal epithelial tumors (NADETs). We aim to compare treatment outcomes, including submucosal resectability, between patients undergoing U-EMR and conventional endoscopic mucosal resection (C-EMR) for NADET.

METHODS

We conducted a retrospective review of 38 patients with NADET treated by U-EMR or C-EMR. In the resected specimens, we measured the horizontal length, the vertical distance from the muscularis mucosa to the margin at the deepest site, and the overall submucosal area. The submucosal index (SMI) was defined as the overall submucosal area divided by the largest horizontal length. These values and other treatment outcomes were compared between NADETs resected by U-EMR and C-EMR.

RESULTS

The median size of lesions was 7 mm with a range of 3-13 mm. Although the incidence of adverse events and the rates of en bloc and R0 resection were not different in the two groups, the median procedure time was significantly shorter in the U-EMR group (11 min vs 13 min; P = 0.045). The median submucosal depth at the deepest site (1.22 mm vs 1.08 mm; P = 0.38) and the median SMI (0.44 vs 0.41; P = 0.42) were not different between groups.

CONCLUSIONS

The resectability between NADETs treated by U-EMR and C-EMR was comparable. These results, together with the shorter procedure time required for U-EMR, suggest that U-EMR may have the potential to be the first choice for small to medium-sized NADET.