Endoscopic Mucosal Resection Technique Research Articles

Interventional inflammatory bowel disease: current and future practice.

Inflammatory bowel diseases (IBD) are associated with several well described neoplastic and structural complications. Increasing disease prevalence, healthcare barriers, and medication refractory phenotypes contribute to ongoing complications despite significant strides in medical management. Enhancements in endoscopic technology and techniques have allowed a minimally invasive approach for what has historically required surgery. In this article, we review the current and future landscape of endoscopic IBD intervention. Endoscopic resection is the first line for managing conventional and complex colitis-associated dysplasia. Evidence supporting endoscopic submucosal dissection is mounting, yet there is a paucity of studies evaluating modified endoscopic mucosal resection techniques or hybrid endoscopic submucosal dissection. We also have more clarity in how best to approach fibrostenotic disease, as we learn how to position endoscopic stricturotomy and stenting, relative to balloon dilation. Finally, applications in managing penetrating and postsurgical complications have been described, but still require further study. While important knowledge gaps still exist, the application of endoscopic therapies in IBD is more refined, especially within the management of colitis-associated dysplasia and strictures. The indications for endoscopy in perianal disease and other penetrating manifestations of Crohn's disease presents exciting opportunities for growth.

Endoscopic mucosal resection techniques for colorectal polyps

Endoscopic mucosal resection techniques for colorectal polyps

Endoscopic treatment of colorectal polyps and early colorectal cancer

Background: Colonoscopy offers higher diagnostic sensitivity than other colorectal cancer screening methods and provides the advantage of both diagnostic tissue sampling and polyp removal. Since the majority of colorectal cancers evolve from adenomatous polyps, polyp resection through colonoscopy is widely considered an effective method of preventing colorectal cancer and reducing mortality rates.Current Concepts: Determining colorectal polyp size and shape requires comprehensive endoscopy with enhanced imaging techniques to choose treatment directions and the appropriate colorectal polypectomy method. The selection of the polypectomy method is contingent upon the polyp’s attributes and possible malignancy according to US Multi-Society Task Force on Colorectal Cancer and European gastrointestinal endoscopy guidelines. This article examines eight polypectomy procedures: cold forceps polypectomy, hot biopsy polypectomy, cold snare polypectomy, hot snare polypectomy, endoscopic mucosal resection (EMR), and modified EMR techniques. Each method has unique benefits and is suitable for particular polyp types and sizes. Piecemeal EMR and endoscopic submucosal dissection offer alternatives for larger or challenging lesions that require careful planning and follow-up. After endoscopic resection of early colorectal cancer, further surgery may be necessary depending on the risk of lymph node metastasis as determined by specific histologic findings following Korean and Japanese guidelines.Discussion and Conclusion: The choice of endoscopic resection technique, which depends on factors such as polyp shape, size, and location as well as endoscopist skill, is crucial for ensuring complete polyp removal.

Endoscopic resection of a large ampullary tumor using a hybrid endoscopic submucosal dissection and mucosal resection technique.

Endoscopic resection of a large ampullary tumor using a hybrid endoscopic submucosal dissection and mucosal resection technique.

Retrospective comparison of G-EYE balloon-colonoscopy with standard colonoscopy for increased adenoma detection rate and reduced polyp removal time.

Background and study aims The newly introduced G-EYE colonoscope (G-EYE) employs a balloon, installed at the bending section of a standard colonoscope (SC), for increasing adenoma detection and stabilizing the colonoscope tip during intervention. This retrospective work explores the effect of introducing G-EYE into an SC endoscopy room, in terms of adenoma detection and polyp removal time. Patients and methods This was a single-center, retrospective study. Historical data from patients who underwent colonoscopy prior to, and following, introduction of G-EYE into a particular endoscopy room were collected and analyzed to determine adenoma detection rate (ADR), adenoma per patient (APP), and polyp removal time (PRT), in each of the SC and G-EYE groups. Results Records of 1362 patients who underwent SC and 1433 subsequent patients who underwent G-EYE colonoscopy in the same endoscopy unit by the same endoscopists were analyzed. Following G-EYE introduction, overall ADR increased by 37.5 % ( P < 0.0001) from 39.2 % to 53.9 %, the serrated adenoma rate increased by 47.3 % from 27.9 % to 41.1 % ( P < 0.0001), and the APP increased by 50.6 % from 0.79 to 1.19 ( P < 0.0001). The number of advanced adenomas increased by 32.7 %, from 19.6 % to 26.0 % of all adenomas ( P < 0.0001). With G-EYE, average PRT was reduced overall by 29.5 % ( P < 0.0001), and particularly for endoscopic mucosal resection (EMR) by 37.5 % for polyps measuring ≥ 5 mm to ≤ 20 mm ( P < 0.0001) and by 29.4 % for large polyps > 20 mm ( P < 0.0001). Conclusions Introduction of G-EYE to an SC endoscopy room yielded considerable increase in ADR and notable reduction in PRT, particularly with the EMR technique. G-EYE balloon colonoscopy might increase the effectiveness of colorectal cancer screening and surveillance colonoscopy, and can shorten the time of endoscopic intervention.

Cold snare and ablation technique for endoscopic mucosal resection of incompletely resected large laterally spreading tumors.

Cold snare and ablation technique for endoscopic mucosal resection of incompletely resected large laterally spreading tumors.

Current status of the role of endoscopy in evaluation and management of gastrointestinal and pancreatic neuroendocrine tumors.

The incidence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has increased over the last several decades. In general, NETs are slow-growing neoplasms and the data on the natural history is still evolving. The availability and improved utilization of advanced imaging modalities have allowed the selection of cases suitable for endotherapy. In this regard, endoscopic ultrasound (EUS) has emerged as a central imaging modality to assess the depth of infiltration in gastroduodenal as well as rectal NETs. Enhanced EUS modalities, including contrast-enhanced EUS and EUS elastography, reliably differentiate pancreatic neuroendocrine tumors (PNETs) from adenocarcinomas and may enable prediction of aggressive PNETs. With recent developments in therapeutic endoscopy, a large proportion of GEP-NETs can be safely managed endoscopically. Endoscopic resection techniques, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), allow the safe removal of gastroduodenal and rectal NETs. Recent data indicate that modified EMR techniques may be superior to conventional EMR with regard to histologically complete resection. Device-assisted endoscopic full thickness resection is emerging as a safe and effective technique for upper gastrointestinal as well as rectal NETs. In selected cases with PNETs, who are otherwise unfit for surgery, EUS-guided ablation is increasingly being recognized as a safe treatment option. This review focusses on evidence-based approaches to endoscopic evaluation and the management of GEP-NETs with special emphasis on recent advancements.

Three-arm endoscopic mucosal resection for gastric adenocarcinoma of fundic gland type.

A 65-year-old man was diagnosed with intramucosal carcinoma by endoscopy and pathological biopsy; the tumor was 10 mm in size and located in the greater curvature of the gastric body ([Fig. 1 a]). It was difficult to perform endoscopic submucosal dissection (ESD) on the greater curvature of the gastric body. We therefore proposed a three-arm endoscopic mucosal resection (TA-EMR) technique in which two nasal oxygen tubes, about 80 cm in length, were taped to the outside of the endoscope to become a double additional working channel (AWC) ([Video 1]).

Conventional endoscopic mucosal resection versus modified endoscopic mucosal resection for duodenal neuroendocrine tumor.

As the incidence of duodenal neuroendocrine tumors (DNET) is steadily increasing, the role of endoscopic treatment for appropriate lesions is becoming more significant. We aimed to compare the outcomes according to lesion size and endoscopic mucosal resection (EMR) techniques for DNET treatment. Patients who underwent endoscopic treatment for DNET between June 2000 and December 2019 were included. The clinicopathologic features and treatment outcomes were investigated by reviewing medical records. Overall, 104 cases underwent endoscopic resection for nonampullary DNET, including conventional EMR (n = 57), cap-assisted EMR (EMR-C, n = 19), and precut EMR (EMR-P, n = 28). The en bloc resection rates (100% vs. 94.7% vs. 96.4%) and histologic complete resection rates (45.6% vs. 52.6% vs. 57.1%) were not significantly different between the EMR, EMR-C, and EMR-P groups. The histologic complete resection rates were significantly higher in lesions < 10mm than in lesions ≥ 10mm (69.8% vs. 38.9%, P = 0.013). In lesions < 10mm, perforation occurred more frequently in the modified EMR group than in the conventional EMR group (13.2% vs. 0.0%, P = 0.007). During the median follow-up period of 88.0months, the recurrence-free survival (92.2% vs. 94.4% vs. 92.1%) and overall survival (98.0% vs. 88.1% vs. 100.0%) rates did not show significant differences between the EMR, EMR-C, and EMR-P groups. Conventional EMR and modified EMR are feasible and effective for the treatment of nonampullary DNET sized < 10mm and limited to mucosal and submucosal layer. Additionally, endoscopists should be aware of the high risk of perforation in modified EMR.

Effective, safe and efficient porcine model of Forrest Ib bleeding gastric and colonic ulcers.

Developing effective gastrointestinal (GI) bleeding animal models is necessary to advance endoscopic hemostasis methods and train endoscopists on their use. Our aim, therefore, was to develop an effective and safe porcine GI bleeding model in the stomach and colon of large and small-sized oozing-type ulcers. Gastric and colonic bleeding ulcers were created using either a hybrid endoscopic submucosal dissection (ESD) technique or a cap-assisted endoscopic mucosal resection (EMR-C) technique in 14 pigs. Prior to ulcer creation, animals were treated with either oral apixaban or intravenous (IV) unfractionated heparin anticoagulation in combination with clopidogrel and aspirin. The primary outcome was the technical success of inducing oozing-type Forrest Ib bleeding ulcers. Secondary outcomes included ulcer diameter, number, creation time and the number of complications associated with each technique. Using hybrid ESD and IV heparin anticoagulation, bleeding was observed in 21/23 (91.3%) gastric ulcers and 6/7 (85.7%) colonic ulcers created. The mean diameter and ulcer creation time were 2.3 ± 0.3cm and 5.3 ± 0.5min, respectively, for gastric ulcers and 2.2 ± 0.4cm and 4.06 ± 0.6min, respectively, for colonic ulcers. Using EMR-C and IV heparin anticoagulation, bleeding was observed in 14/15 (93.3%) gastric ulcers and 6/6 (100%) colonic ulcers created. The mean diameter and ulcer creation time were 0.8 ± 0.2cm and 2.1 ± 0.5min, respectively, for gastric ulcers and 0.7 ± 0.2cm and 1.7 ± 0.3min, respectively, for colonic ulcers. None of the ulcers created in animals anticoagulated with apixaban developed bleeding. None of the 14 pigs developed any complications. We have demonstrated the effectiveness and safety of a porcine GI bleeding model utilizing IV heparin anticoagulation and either hybrid ESD or EMR-C techniques to create oozing-type bleeding ulcers in the stomach and colon with customizable size.

Two-Endoscope Technique of Endoscopic Mucosal Resection for the Treatment of Gastric Intestinal Metaplasia

Background and Aim: Gastric intestinal metaplasia (GIM) is precancerous with a worldwide prevalence of 25%. Eradicating Helicobacter pylori prevented about half of gastric cancers; failure to prevent the rest was attributed to GIM. GIM is irreversible and often extensive. There is no treatment. Existing endoscopic mucosal resection (EMR) is designed to treat early gastric cancer of usually &lt;2 cm. A two‐endoscope technique of EMR for extensive GIM had been designed and successfully applied. Our aim is to describe the technique in detail. Two-endoscope technique of endoscopic mucosal resection: Patients with histologically confirmed moderate to severe GIM (operative link on GIM [OLGIM] classification) received the treatment in a daycare center. Chromoendoscopy with methylene blue was first performed to disclose and mark the GIM. Submucosal saline injections were used to lift the stained mucosa to form multiple safety cushions, which were then transformed into artificial polyps by suction and ligation, using a cap for ligation of esophageal varices. EMRs were then achieved by snare polypectomy. By rotating two gastroscopes, one designated to perform lift and snare and the other to perform suction and ligation, cycles of lift–ligate–snare were carried out until all stained mucosa was removed. Assessment chromoendoscopy with ≥seven biopsies was performed at 6 months. Results: A total of 227 EMRs were performed in 40 patients, with a median of 3.5 per patient. Bleeding was uncommon and minimal. Gastric perforation ascribable to loss of a safety cushion occurred in one patient. Chromoendoscopy at 6 months in 36 willing patients showed no recurrence of GIM. Conclusion: The two‐endoscope technique of EMR for GIM was essentially safe and effective, with no recurrence at 6 months. It could be performed by endoscopists with standard skills.

Need for adjunctive removal techniques for endoscopic mucosal resection of large non-pedunculated colonic polyps is predictive of recurrence

Abstract Background and study aims Endoscopic mucosal resection (EMR) allows for safe and effective removal of large non-pedunculated colon polyps, but recurrence remains a significant concern. Risk factors for recurrence have previously been reported, however, the significance of these factors have varied and has uncertain applicability with recent advances in EMR techniques. We aimed to evaluate rates and risk factors for recurrence in recent years from a major Canadian referral center. Patients and methods Consecutive patients between April 1, 2017 and March 1, 2019 who underwent piecemeal EMR were retrospectively identified. Patients with non-pedunculated colorectal polyps ≥ 2 cm removed by piecemeal EMR with available follow-up data were included. Results Five hundred and seventeen patients were reviewed, with 265 patients satisfying inclusion criteria. The median age was 67 years (IQR 14); 48 % were female. 15 % had a recurrence on follow-up endoscopy. Adjunctive removal techniques were utilized in 31 % of patients, 95 % of which was hot avulsion. The use of adjunctive removal techniques (OR 2.87, P = 0.004) and male gender (OR 3.31, P = 0.003) was significantly predictive of recurrence on multivariate analysis. Receiver operating curve characteristics demonstrated good performance of these factors in predicting recurrence (area under the curve = 0.70). Conclusions The use of adjunctive removal techniques, particularly hot avulsion and male gender are predictive of recurrence after piecemeal EMR of large non-pedunculated colorectal polyps. Male patients and those who require hot avulsion may be considered high risk for recurrence and warrant closer follow-up.

Evolution of endoscopic mucosal resection (EMR) technique and the reduced recurrence of large colonic polyps from 2012 to 2020

Background Endoscopic mucosal resection (EMR) is an effective method for removing non-pedunculated polyps ≥ 20 mm. We aimed to examine changes in EMR techniques over a 9-year period and evaluate frequency of histologic-confirmed recurrence. Methods We identified patients who underwent EMR of non-pedunculated polyps ≥ 20 mm at a safety net and the Veteran’s Affairs (VA) hospital in Houston, Texas between 2012 and 2020. Odds ratios (ORs) and 95% confidence intervals (CI) for associations with recurrence risk were estimated using multivariable logistic regression. Results 461 unique patients were included. The histologic-confirmed recurrence was 29.0% at 15.6 months median follow up (IQR 12.3 − 17.4). Polyps removed between 2018 and 2020 had a 0.43 decreased odds of recurrence vs. polyps removed between 2012 and 2014. The use of viscous lifting agents increased over time (from 0 to 54%), and the use of saline was associated with increased risk of recurrence (OR 2.28 [CI 1.33 − 3.31]). Conclusions Histologic-confirmed recurrence after EMR for non-pedunculated polyps ≥ 20 mm decreased over the seven year-period. Saline was associated with a higher risk of recurrence and the use of more viscous agents increased over time.

S3657 Primary Gastric Adenocarcinoma With Clear Cell Differentiation Presenting With Melena: A Rare Cancer Treated With Hybrid Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection

Introduction: Primary gastric clear cell carcinoma (GCCC) is an exceedingly rare type of adenocarcinoma. It can often be misdiagnosed as metastatic clear cell cancer with primary lesions in other body organs. We hereby present an interesting case of primary GCCC, successfully removed with hybrid endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). Case Description/Methods: A 91-year-old male had ongoing anemia and melena due to intermittent oozing from a gastric body nodule. Previous EGD showed an oozing, nodular lesion in the gastric body (Figure 1A). On EUS, it was a benign, mucosal-based, friable lesion. Pathology revealed gastric intestinal metaplasia. His past history included hyperlipidemia, hypertension, skin cancer, transient ischemic attack, prior colon polyps, and sigmoid resection for diverticulosis. Home medications included cardizem, iron and vitamin C supplements, allopurinol, aspirin, and PPI. He denied recent weight loss, nausea, vomiting, early satiety, chest pain, dyspnea, fever, or dysphagia. He then came to our hospital for endoscopic removal of the gastric lesion. EGD showed a 3-cm sessile polyp on the posterior wall of the gastric body, located along the lesser curvature (Figure 1B, C). The polyp was completely removed by the hybrid EMR and ESD technique. Pathology revealed invasive adenocarcinoma of the intestinal type with clear cell features, arising in a background of extensive intestinal metaplasia (Figure 1; D, E, F). He developed post-procedure urinary retention and underwent temporary Foley's catheter placement, which was removed shortly after. No fever or GI bleeding was noted. After diagnosis, his oncologist recommended concurrent chemoradiotherapy. His most recent PET scan was unremarkable. No melena was reported at the follow-up after 3 months. Discussion: We herein presented a rare and interesting case of primary GCCC. In these patients, it is imperative for endoscopists to differentiate between primary GCCC and metastatic lesions to deliberate upon best therapeutic choice. Pathology with immunohistochemistry is the cornerstone of accurate diagnosis for primary GCCC. Given the extremely rare occurrence, no standard treatment guidelines exist for GCCC. Therefore, the therapeutic approach varies on a case-by-case basis, which largely depends on its localization. For instance, the 3-cm lesion in our patient was located along the lesser curvature and was successfully removed by hybrid EMR and ESD. Therefore, it did not necessitate total gastrectomy.Figure 1.: A: Previous EGD showing an actively oozing, nodular lesion in the gastric body. B and C: EGD showing a 3-cm sessile polyp on the posterior wall of the gastric body, located along the lesser curvature. D, E, and F: Pathologic examination of the polypectomy specimen showing invasive adenocarcinoma of the intestinal type with clear cell features, arising in a background of extensive intestinal metaplasia.

Efficacy and Safety of a Novel Triple-anchoring Technique for Colonic Hybrid Endoscopic Mucosal Resection: A Case Series.

A hybrid technique may be a reasonable compromise to make endoscopic mucosal resection (EMR) more reliable for lesions ≥ 20 mm and a good way of approaching to endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy and safety of a novel hybrid EMR technique, triple-anchoring EMR (T-EMR) for colorectal lesions 20-30 mm. Fifteen patients have been prospectively enrolled to T-EMR from December 2019 to April 2020 in two Endoscopy Units: Policlinico A. Gemelli, Rome, and University Hospital of Udine, Italy. Patients eligible for the study were ≥18 years old with superficial colorectal lesions 20-30 mm, morphologically liable to endoscopic treatment based on chromoendoscopy. The primary endpoint was assessment of the "en bloc" and the free resection margins (R0) rates. The secondary endpoints were resected specimen size, procedure time, complication rate, and recurrence rate at 6 months. Among the 15 patients enrolled, 12 were males (80%), mean age 68.73±11.04 years. The mean size of the lesions was 24.93±2.89 mm. Mean procedure time was 22.13±4.31 min. T-EMR was performed en bloc in 14/15 patients (93.3%) with R0 in 13/15 patients (86.7%). No major intra-/peri-procedural or delayed complications occurred. At histological analysis, 13/15 lesions (86.7%) were adenomas, while 2 were early colorectal cancer. At a 6-month follow-up colonoscopy, only one patient (6.7%) had a recurrence of adenoma. T-EMR seems to be an effective and safe option to treat colorectal lesions between 20 and 30 mm, with a short procedure time and low costs.

EMR and ESD: Indications, techniques and results

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are two well-known endoscopic resection procedures used for advance gastrointestinal lesions. As compared to standard polypectomy techniques, EMR and ESD provide wider and deeper resection margins and allow en bloc removal of lesions for more detailed pathology with curative intent for early neoplastic gastrointestinal lesions. Both procedures have their advantages and disadvantages which will be discussed in detail in this review article. Recently there have been advancements in the techniques of EMR and ESD with addition in new equipment. We will also discuss current guidelines recommending use of EMR and/or ESD in various clinical scenarios.

A122 OUTCOMES OF COLD SNARE POLYPECTOMY FOR POLYPS GREATER THAN 20 MM: DATA FROM AN ACADEMIC CENTER

BackgroundCold snare polypectomy (CSP) is widely utilized for resection of small polyps (less than 10mm), due to the technique’s favourable safety profile. However, Hot Snare Endoscopic Mucosal Resection (HSEMR) remains the standard of care for large polyps greater than or equal to 20mm. HSEMR carries an increased risk of complications. These include delayed bleeding, perforation, and post-polypectomy syndrome, along with residual or recurrent adenomatous (RRA).More recently, Cold Snare Endoscopic Mucosal Resection (CSEMR) technique has been used selectively for polyps greater than 20mm. Published studies have demonstrated a significantly lower adverse event rate of complications as compared with HSEMR. RRA utilizing CSP remains a concern, with a recent publication reporting a recurrence of 34.8% on follow-up endoscopy. We present the experience at a single Canadian academic centre with patients undergoing CSEMR for polyps greater than 20mm.AimsTo demonstrate the efficacy and safety of cold snare endoscopic mucosal resection CSEMR of large (greater than or equal to 20mm) polyps at a single Canadian academic centre.MethodsWe retrospectively reviewed colonoscopies performed by endoscopists employing this technique at our centre from January 2020 to August 2021. 15 total cases were identified for patients with polyps greater than or equal to 20 mm, removed by CSEMR technique.ResultsPatient age ranged from 41 to 76, with a median patient age was 66. There were 10 males and 5 females. There were no adverse events intraoperatively. 15/15 (100%) polyps were successfully resected using CSEMR technique. Polyp size ranged from 2 cm to 7 cm, and there was a median polyp size of 3 cm. 14/15 (93%) polyps were proximal to the splenic flexure, with 1/15 (7%) polyp in the rectum. 6/15 (40%) patients received snare tip soft coagulation to the edges of the polypectomy site. Polyp histology included 7 tubular adenomas, 3 tubulovillous adenomas, 4 sessile serrated polyps, and one hyperplastic polyp. Two patients were on aspirin 81 mg daily, and there were zero patients on any other antiplatelets or anticoagulation. 1/15 patient presented with late bleeding requiring emergent colonoscopy. There were no immediate or delayed perforations or other serious adverse events recorded.Approximately 50% of patients have had follow-up colonoscopy within 3–6 months of their initial procedure. Follow-up ranged from 12 to 252 days, with a median time to follow up of 171 days. 3/7 (43%) patients had histologic evidence of recurrence at follow-up colonoscopy, all of which were successfully treated endoscopically.ConclusionsSelective CSEMR is a safe and effective technique, with a low risk of complications. There may be a higher rate of residual polyp at follow-up colonoscopy compared to HSEMR. This data will need further validation with a larger sample size. Funding AgenciesNone

Wide-field endoscopic mucosal resection of laterally spreading rectaltumors using a multiband ligation endoscopic mucosal resection technique.

Video 1Tools and techniques video introducing and demonstrating the multiband ligation-assisted EMR technique to achieve wide-field endoscopic mucosal resection of large rectal laterally spreading tumors.

Advanced Endoscopic Imaging and Interventions in GERD: An Update and Future Directions

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered in primary care and gastroenterology clinics. Most cases of GERD can be diagnosed based on clinical presentation and risk factors; however, some patients present with atypical symptoms, which can make diagnosis difficult. An esophagogastroduodenoscopy can be used to assist in diagnosis of GERD, though only half of these patients have visible endoscopic findings on standard white light endoscopy. This led to the development of new advanced endoscopic techniques that enhanced the diagnosis of GERD and related complications like squamous cell dysplasia, Barrett's esophagus, and early esophageal adenocarcinoma. This is conducted by improved detection of subtle irregularities in the mucosa and vascular structures through optical biopsies in real-time. Management of GERD includes lifestyle modifications, pharmacological therapy, endoscopic and surgical intervention. Minimally invasive endoscopic intervention can be an option in selected patients with small hiatal hernia and without complications of GERD. These endoscopic interventions include endoscopic fundoplication, endoscopic mucosal resection techniques, ablative techniques, creating mechanical barriers, and suturing and stapling devices. As these new advanced endoscopic techniques are emerging, data surrounding the indications, advantages and disadvantages of these techniques need a thorough understanding.

Outcomes of endoscopic resection for superficial duodenal tumors: 10 years' experience in 18 Japanese high volume centers.

Data on endoscopic resection (ER) for superficial duodenal epithelial tumors (SDETs) are insufficient owing to their rarity. There are two main ER techniques for SDETs: endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). In addition, modified EMR techniques, such as underwater EMR (UEMR) and cold polypectomy, are becoming popular. We conducted a large-scale retrospective multicenter study to clarify the detailed outcomes of duodenal ER. Patients with SDETs who underwent ER at 18 institutions from January 2008 to December 2018 were included. The rates of en bloc resection and delayed adverse events (AEs; defined as delayed bleeding or perforation) were analyzed. Local recurrence was analyzed using the Kaplan-Meier method. In total, 3107 patients (including 1017 undergoing ESD) were included. En bloc resection rates were 79.1 %, 78.6 %, 86.8 %, and 94.8 %, and delayed AE rates were 0.5 %, 2.2 %, 2.8 %, and 6.8 % for cold polypectomy, UEMR, EMR and ESD, respectively. The delayed AE rate was significantly higher in the ESD group than in non-ESD groups for lesions < 19 mm (7.4 % vs. 1.9 %; P < 0.001), but not for lesions > 20 mm (6.1 % vs. 7.1 %; P = 0.64). The local recurrence rate was significantly lower in the ESD group than in the non-ESD groups (P < 0.001). Furthermore, for lesions > 30 mm, the cumulative local recurrence rate at 2 years was 22.6 % in the non-ESD groups compared with only 1.6 % in the ESD group (P < 0.001). ER outcomes for SDETs were generally acceptable. ESD by highly experienced endoscopists might be an option for very large SDETs.