Outcomes Of Endoscopic Mucosal Resection Research Articles

Low-power pure-cut hot snare polypectomy for colorectal polyps 10-14mm in size: a multicenter retrospective study.

Hot snare excision using electrocautery is widely used for large colorectal polyps (>10mm); however, adverse events occur due to deep thermal injury. Colorectal polyps measuring 10-14mm rarely include invasive cancer. Therefore, less invasive therapeutic options for this size category are demanding. We have developed hot snare polypectomy with low-power pure-cut current (LPPC HSP), which is expected to contribute to less deep thermal damage and lower risk of adverse events. This study aimed to evaluate the efficacy and safety of LPPC HSP for 10-14mm colorectal polyps, compared with conventional endoscopic mucosal resection (EMR). In this multicenter, retrospective, observational study, clinical outcomes of EMR and LPPC HSP for 10-14mm nonpedunculated colorectal polyps between January 2021 and March 2022 were compared using propensity score matching. We identified 203 EMR and 208 LPPC HSP cases. After propensity score matching, the baseline characteristics between the groups were comparable, with 120 pairs. The en bloc and R0 resection rates were not significantly different between EMR and LPPC HSP groups (95.8% vs 97.5%, P=0.72; 90.0% vs 91.7%, P=0.82). The rates of delayed bleeding and perforation did not differ between the groups. Compared with conventional EMR, LPPC HSP showed a similar resection ability without an increase in adverse events. These results suggest that LPPC HSP is a safe and effective treatment for 10-14mm nonpedunculated colorectal polyps.

Delays in definitive endoscopic resection of previously manipulated colorectal polyps as a risk factor for inferior resection outcomes

Manipulation of colorectal polyps by biopsy, incomplete resection or tattoo placement under the lesion has been shown to cause submucosal fibrosis and associated inferior outcomes. The effect of delays between index manipulation and definitive resection on the incidence of fibrosis is unknown. Patients undergoing endoscopic mucosal resection (EMR) of previously manipulated colorectal polyps ≥ 10 mm between 2016 and 2021 at a tertiary referral center were included. Time from index manipulation to definitive resection and the presence of fibrosis were noted. The effects of fibrosis on EMR outcomes were assessed. Among 221 previously manipulated lesions [180 biopsy, 23 incomplete/failed resection, 1 tattoo under lesion, 17 multiple types of manipulation], 51 (23%) demonstrated fibrosis. Fibrotic lesions were found to have been resected significantly later compared to non-fibrotic lesions (76 vs. 61 days, p=0.014). In a multivariate analysis controlling for other predictors of fibrosis, each 2-week delay was associated a 14% increase in the odds of fibrosis. Fibrotic lesions had inferior outcomes with a lower en-bloc resection rate (8% vs. 24%, p=0.014) and longer procedure time (71 vs. 52 minutes, p=<0.001). Adverse event and recurrence rates were comparable between groups. Delays in definitive resection of previously manipulated polyps are associated with an increased incidence of fibrosis with time and associated inferior outcomes. Manipulation should be discouraged, and if it occurs, prompt referral and scheduling for definitive resection should be prioritized.

Comparing endoscopic mucosal resection with endoscopic submucosal dissection in colorectal adenoma and tumors: Meta-analysis and system review.

This study aimed to evaluate the safety, efficacy, and long-term outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) for treating colorectal adenomas and tumors. A systematic literature review was conducted using databases including PubMed, Web of Science, and Embase. Parameters such as number of patients or lesions, histological diagnosis, lesion size, surgery time, en-bloc resection, R0 resection, severe postoperative complications, and local recurrence were extracted and pooled for analysis. A total of 12 retrospective studies involving 1289 patients and 1850 lesions were included in the analysis. EMR was found to have a shorter operation time by 53.6 minutes (95% CI: 51.3, 55.9, P<0.001) and fewer incidences of severe postoperative complications such as perforation and delayed bleeding (OR = 0.40, 95%CI: 0.23, 0.71, P<0.001). On the other hand, ESD had higher rates of en-bloc resection (OR = 0.15, 95%CI: 0.07, 0.30, P<0.001) and R0 resection (OR = 0.32, 95%CI: 0.16, 0.65, P<0.001). Recurrence after EMR was found to be significantly higher than that after ESD surgery (OR = 5.88, 95%CI: 2.15, 16.07, P = 0.037). The study suggests that the choice of surgical method may have a greater impact on recurrence compared to the pathological type, and that ESD may be more suitable for the treatment of malignant lesions despite its higher rates of severe postoperative complications and longer operation time.

S772 Endoscopic Mucosal Resection for Colorectal Dysplasia in Inflammatory Bowel Disease

Introduction: Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer due to underlying chronic inflammation. Frequent surveillance colonoscopy is essential for early identification and removal of dysplastic lesions in this group. Many dysplastic lesions in IBD require advanced endoscopic resection due to size, morphology, or indistinct margins. The effectiveness of endoscopic mucosal resection (EMR) for laterally spreading lesions is well documented in the general population; however, EMR continues to be challenging in patients with IBD. We aim to characterize outcomes of EMR for IBD-associated lesions compared to controls. Methods: Retrospective data was collected from 2016 to 2021. CPT code 45390 was used to identify colonoscopies with EMR. ICD-10 codes K50-52 were used to identify patients with IBD. Adenomatous and dysplastic lesions of all sizes that were removed with EMR and underwent endoscopic surveillance were included. Data was recorded and stored in a REDCap database and analyzed using a mixed effects model for logistic regression with SAS Statistical Software. Results: A total of 23 lesions in 14 patients with IBD and 187 lesions in 141 patients without IBD were included. Gender, ethnicity, age, lesion size and location, procedure date and duration, and number of lesions per patient were similar among both groups (Table). Piecemeal resection (as opposed to en bloc resection) was more common in the IBD group (91.3% vs. 42.1%, P< .001). Surgical resection was required for 2 IBD-associated lesions and 7 controls (8.7% vs. 3.9%, P=.27). Recurrence was detected and confirmed by histology in 7 IBD-associated lesions and 39 controls. In a mixed effects logistic regression model (Figure), IBD and lesion size were independently associated with recurrence (OR=3.08, 95% CI 1.04-9.13, P=.04; OR=1.06 per mm increase, 95% CI 1.02-1.09, P=.001). For each year that elapsed from the study start date to the procedure date, odds of recurrence decreased by 28% (OR=0.72, 95% CI 0.58-0.90, P=.004). In this model, 38.4% of IBD-associated lesions (95% CI 18.6-58.1) compared to 19.1% of controls (95% CI 13.8-24.5) recurred after EMR. Conclusion: Recurrence of dysplastic lesions after EMR is more common in patients with IBD compared to controls. Most IBD-associated lesions are resected piecemeal. EMR in patients with IBD should be performed in expert centers with close endoscopic surveillance.Figure 1.: Mixed effects logistic regression model estimating odds of recurrence after EMR of adenomatous and dysplastic colorectal lesions. Diagnosis of IBD, lesion size, year of procedure, and degree of dysplasia were incorporated in the model. OR = 3.08 with a diagnosis of IBD (95% CI 1.04-9.13, p=.04). OR = 1.06 with each millimeter increase in lesion diameter (95% CI 1.02-1.09, p=.001). OR = 0.72 with each year from the study start date that elapsed prior to EMR (95% CI 0.58-0.90, P=.004). Table 1. - Characteristics of adenomatous and dysplastic colorectal lesions resected with EMR in patients with IBD compared to controls Total n = 210 Control n = 187 IBD n = 23 P-value Lesion size (mm): mean (SD) 21.7 (12.2) 21.5 (12.4) 22.9 (11.3) .62 Degree of dysplasia: n (%) .81 adenoma/low-grade dysplasia 191 (91.0) 170 (90.9) 21 (91.3) high-grade dysplasia 14 (6.7) 12 (6.4) 2 (8.7) invasive carcinoma 5 (2.4) 5 (2.7) 0 (0.0) Location: n (%) .36 ascending colon 69 (35.8) 61 (35.3) 8 (40.0) transverse colon 44 (22.8) 40 (23.1) 4 (20.0) cecum 29 (15.0) 28 (16.2) 1 (5.0) sigmoid colon 19 (9.8) 18 (10.4) 1 (5.0) descending colon 14 (7.3) 12 (6.9) 2 (10.0) rectum 11 (5.7) 9 (5.2) 2 (10.0) ileocecal valve 7 (3.6) 5 (2.9) 2 (10.0) Procedure time (min): mean (SD) 74.1 (29.9) 73.3 (30.4) 80.6 (25.5) .27 En-bloc vs piecemeal resection: n (%) < .001 en-bloc 108 (52.4) 106 (57.9) 2 (8.7) piecemeal 98 (47.6) 77 (42.1) 21 (91.3) Complications: n (%) 11 (5.2) 9 (4.8) 2 (8.7) .34

Outcomes of endoscopic mucosal resection for large superficial non-ampullary duodenal adenomas

Endoscopic mucosal resection (EMR) is the recommended treatment for superficial non-ampullary duodenal epithelial tumors larger than 6 mm. This endoscopic technique carries a high risk of adverse events. Our aim was to identify the risk factors for adverse events following EMR for non-ampullary duodenal adenomatous lesions. We retrospectively analyzed a prospectively collected database of consecutive endoscopic resections for duodenal lesions at a tertiary referral center for therapeutic endoscopy. We analyzed patients with non-ampullary duodenal adenomatous lesions ≥ 10 mm resected by EMR, and searched for factors associated with adverse events after EMR. 167 duodenal adenomatous lesions, with a median size of 25 (25–40) mm, were resected by EMR between January 2015 and December 2020. Adverse events occurred in 37/167 (22.2%) after endoscopic resection, with 29/167 (17.4%) delayed bleeding, 4/167 (2.4%) immediate perforation and 4/167 (2.4%) delayed perforation. In logistic regression, the size of the lesion was the only associated risk factor of adverse events (OR = 2.81, 95% CI [1.27; 6.47], p = 0.012). Adverse events increased mean hospitalization time (7.7 ± 9 vs. 1.9 ± 1 days, p < 0.01). None of the currently recommended preventive methods, particularly clips, affected the adverse event rate. EMR of centimetric and supracentimetric duodenal adenomatous lesions carries a high risk of adverse events, increasing with the size of the lesion and with no benefit from any preventive method. These results suggest that these procedures should be performed in expert centers, and underline the need for novel endoscopic tools to limit the rate of adverse events.

Risk factors for local recurrence of large gastrointestinal lesions after endoscopic mucosal resection.

Endoscopic mucosal resection (EMR) is the primary treatment modality for superficial gastrointestinal mucosal lesions > 2cm. However, the procedure carries some risk of complications including bleeding, perforation, and local recurrence. This study aimed to examine factors associated with EMR outcomes, especially in terms of local recurrence. This study retrospectively evaluated patients who underwent EMR and full closure with prophylactic clips for upper and lower gastrointestinal lesions > 2cm at Cleveland Clinic Florida, between January 2013 and December 2018 with follow-up endoscopic evaluation for recurrence. A total of 2031 endoscopic polypectomy cases were examined; 307 EMR procedures among 271 patients (52% were female, mean age 65.6 ± 11.1years) who satisfied the inclusion criteria were included in the study. There were no perforations reported. The rate of post-polypectomy delayed bleeding was 1.6%, and the local recurrence rate in this cohort was 7.1%. Recurrent cases were successfully endoscopically managed. In the multivariate regression analysis, age > 70years (OR = 3.20, 95% CI 1.17-8.76, p = .023), body mass index (OR = 1.12, 95% CI 1.03-1.23 p = .008), and lesion size ≥ 35mm (OR = 11.51, 95% CI 3.54-37.40, p = < .001) were independent predictors for recurrence. Age > 70years, increased lesion size, and obesity were found to be independent predictors of local recurrence among EMR procedures for gastrointestinal lesions > 2cm. However, there is a need for larger-scale studies on this topic.

To investigate outcomes in endoscopic management of early oesophageal adenocarcinoma in Barrett oesophagus: experience at three Australian tertiary centres.

Barrett oesophagus is a known precursor of oesophageal adenocarcinoma (EAC). Early EAC includes T1a (invasion into mucosa) and T1b (invasion into submucosa but not muscularis propria). Endoscopic mucosal resection (EMR) provides accurate histological staging and definitive treatment for early EAC. Post EMR, the remaining Barrett is eradicated with radiofrequency ablation (RFA). However, there is a paucity of long-term Australian data. To investigate the efficacy and long-term outcomes of EMR and RFA in the management of early EAC. Retrospective analysis of patients early EAC treated endoscopically at three Western Australian tertiary centres, with at least 12-months follow up, over the past 10 years. Sixty-seven patients with early EAC (61 T1a and 6 T1b) were treated with EMR. Complete Barrett eradication was done by EMR in 31 of 67 patients whereas 36/67 patients underwent RFA for residual Barrett. EMR changed pinch biopsy histology from HGD (n = 33), HGD suspicious for IMC (n = 5) and LGD (n = 1) to early EAC in 58.2% (n = 39) patients. During a mean follow up of 37.2 months (interquartile range: 20, 56), complete remission of dysplasia and intestinal metaplasia was seen in 97% (n = 65) and 89.5% (n = 60) patients. One patient with T1b EAC underwent oesophagectomy. No cases developed metachronous EAC, progression to invasive adenocarcinoma or development of nodal/distant metastasis. Complications were endoscopically treated haematemesis (n = 1) and strictures (n = 16) requiring dilatations. Three patients died due to causes unrelated to IMC. EMR in conjunction with RFA is an effective and safe management for early EAC. EMR provides accurate staging and has low complication rates.

A127 ENDOSCOPIC MUCOSAL RESECTION FOR DYSPLASTIC AND NEOPLASTIC BARRETT’S ESOPHAGUS: FINDINGS FROM A FOREGUT NEOPLASIA MULTIDISCIPLINARY DATABASE

Abstract Background Previously, Barrett’s esophagus with high grade dysplasia (HGD) or neoplasia was treated with esophagectomy, which is associated with a high postoperative morbidity and mortality rate. Recent guidelines support the use of endoscopic mucosal resection (EMR) for T1a esophageal adenocarcinoma (EAC) and potentially T1b EAC; however, data on long term outcomes of endoscopic treatment is lacking. We created a combined prospective and retrospective multidisciplinary database to monitor outcomes of patients with Barrett’s esophagus undergoing endoscopic treatment. Aims Our primary aim was to compare outcomes of EMR and esophagectomy in patients presenting with BE and HGD, and/or early EAC. Methods A collaboration of gastroenterologists, general surgeons and thoracic surgeons from the University of Alberta, Edmonton, Alberta, provided input on the development of the database. All patients referred to the Northern Alberta Endoscopic Ablation Program from 2009–2021 who received at least one endoscopic treatment were included. A sub-analysis of all patients with pathologic confirmation of HGD, and/or early EAC was conducted to compare outcomes of EMR and esophagectomy. Results A total of 212 patients have been entered into the database. The most common findings were HGD, low grade dysplasia (LGD), and adenocarcinoma, respectively. All patients (n=48) who had at least LGD reached complete eradication of dysplasia (CE-D) and 95.8% reached complete eradication of intestinal metaplasia (CE-IM). Of those patients that reached CE-D, 8.3% developed recurrence of dysplasia (n=4). In the sub-analysis, 74 patients (76.3%) received endoscopic therapy while 23 patients (23.7%) received endoscopic therapy then ultimately an esophagectomy. There were significantly more T1b lesions in the esophagectomy group compared to the EMR group ( p&amp;lt;0.0001). Of all the patients in the EMR group, only 5.4% (n=4) had treatment related complications. Of patients receiving an esophagectomy, 60.9% (n=14) experienced treatment related complications. The mean length of stay for patients in the EMR group was 1.03 +/- 0.2 days, compared to 16.5 +/- 11.8 days for esophagectomy ( p&amp;lt;0.0001). Conclusions EMR provides definitive and durable treatment for BE lesions classified as T1b or less severe, with fewer complications and a shorter length of hospital stay than esophagectomy. Funding Agencies Alberta Innovates Health Solutions

Advanced Endoscopic Resection Techniques in Cirrhosis-A Systematic Review and Meta-Analysis of Outcomes.

While safety and effectiveness of advanced endoscopic resection techniques such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) has been well established in general population, data regarding their utility in patients with cirrhosis is limited. We searched multiple databases from inception through July 2021 to identify studies that reported on outcomes of EMR and/or ESD in patients with cirrhosis. Meta-analysis was performed to determine pooled rates of immediate and delayed bleeding, perforation, death as well as rates of successful en bloc and R0 resection. Pooled relative risk (RR) was calculated for each outcome between patients with and without cirrhosis. Ten studies with a total of 3244 patients were included in the final analysis. Pooled rates of immediate & delayed bleeding, perforation, and death during EMR and/or ESD in patients with cirrhosis were 9.5% (CI 4.0-21.1), 6.6% (CI 4.2-10.3), 2.1% (CI 1.1-3.9) and 0.6% (CI 0.2-1.7), respectively. Pooled rates of successful en bloc and R0 resection were 93% (CI 85.9-96.7) and 90.8% (CI 86.5-93.8), respectively. While incidence of immediate bleeding was higher in patients with cirrhosis, there was no statistically significant difference in any of the other outcomes between the patient groups. Our study shows that performing EMR and ESD for gastrointestinal lesions in patients with cirrhosis is both safe and effective. The risks of procedural complications parallel those reported in general population.

Long-term outcomes of endoscopic mucosal resection for early-stage esophageal adenocarcinoma.

With growing application of endoscopic therapy for early-stage esophageal cancer, we sought to review our experience of endoscopic mucosal resections (EMRs). The aim of our study was to understand the natural course of these patients, especially with positive margins. A prospectively maintained database of all patients undergoing endoscopic therapies at Georgetown University Hospital for esophageal cancer was used for the analysis between 2010 and 2020. Of 80 patients in the EMR database, 35 were performed as index cases for esophageal adenocarcinoma. Majority (74.3%) had a pre-treatment ultrasound confirming absence of regional adenopathy. There were no post-EMR bleeding or perforation events requiring re-intervention. Complete R0 resection was achieved in 22/35 (62.9%) after initial EMR. Thirteen patients had positive margins. Of these 13 patients, only 7 patients underwent repeat endoscopic resection, 2 underwent subsequent esophagectomy, 2 received definitive radiation given poor surgical candidacy, and 2 were lost to follow-up. Overall and 5-year survival of all patients undergoing EMR was 67.9months and 85%, respectively. Subset analysis of the 13 patients with R1 resection demonstrated an overall survival of 49.2months and 60% 5-year survival vs overall survival of 78.9months and 93% 5-year survival for R0 resection. At a median follow-up of 60.5months, cancer recurrence occurred in 3 patients. All of them were successfully managed with repeat EMR. Endoscopic resections represent a safe and effective treatment for early-stage esophageal cancer. Patients with high-risk features should be counseled to undergo an esophagectomy if they are operable candidates.

ASO Author Reflections: Endoscopic Management is Reasonable for &lt;2 cm Duodenal Neuroendocrine Tumors

Optimal management of duodenal neuroendocrine tumors (DNETs) has not been well-defined, especially for DNETs 1-2 cm in size. Recent studies comparing endoscopic mucosal resection (EMR) and surgical resection demonstrate EMR is safe and effective for these intermediate-sized DNETs. Expert and consensus guidelines could consider updating recommendations to reflect the outcomes of EMR in DNETs and the importance of endoscopic surveillance in these patients to evaluate for local recurrence.

Endoscopic mucosal resection and conventional polypectomy in colon adenomas

Aim: to compare the early and long-term results of endoscopic mucosal resection (EMR) and conventional polypectomy for benign epithelial colon neoplasmsPatients and methods: the retrospective study included 344 patients with histologically verified adenomas of the size of up to 40 mm in the colon, who underwent EMR or conventional polypectomy. Mucosectomy (EMR) was performed in 207 patients, while conventional polypectomy was performed in 137.Results: there were no significant differences in the postoperative morbidity rates between the methods (OR = 1.8; 95% CI = 0.7–4.8, p = 0.3). Fragmentation significantly more often occurred in the group of conventional polypectomy (OR = 3.5; 95% CI = 2.3–5.5, p = 0.001, especially when the size of the neoplasm was over 1 cm (OR = 3.1; 95% CI = 1.1–8.9 = 0.037). Recurrence occurred in 19/173 (10.9%) in 12 (8.3%) patients of the EMR group. In the polypectomy group, recurrence developed in 22 (23.1%) patients, in 24/108 (22.2%) cases at the site of the postoperative scar. It was found that the adenoma recurrence in the area of endoscopic excision occurs significantly more often after conventional polypectomy (OR = 2.3; 95% CI = 1.2–4.4; p = 0.016).Conclusion: EMR and conventional polypectomy both are the safe methods with low morbidity rates. However, the EMR is the preferred method of endoscopic excision for adenomas larger than 1 cm due to the fact that it allows for deeper and more complete resection of the tissue than conventional polypectomy.

Endoscopic mucosal resection of large colonic laterally spreading tumors using a dedicated viscous solution for submucosal injection (ORISE gel): a short case series (with video).

Endoscopic mucosal resection (EMR) of large (>20 mm) laterally spreading tumors (LSTs) was usually rescheduled to guarantee experienced operator and enough endoscopic schedule time. The use of viscous solutions allows a reduction in repeated injections, snare resections and procedural time. The aim was to describe the outcome of EMR of large LSTs performed at the time of index colonoscopy, using ORISE gel (Boston Scientific). A retrospective analysis was performed retrieving patients who underwent EMR of large colonic LSTs at the time of index colonoscopy. EMR was performed after dynamic injection of ORISE gel to create a submucosal cushion. Procedural parameters, together with pathological and endoscopic outcomes, were analyzed. Five patients [three males, median age 65 (45-70) years] were included. Median LST size was 35 mm (25-40). Median procedure time was 8 min (range 3-13). En bloc resection was achieved in one out of five cases; four out of five were planned as piecemeal resections. A median of 10 mL (10-20) of viscous solution was injected. R0 resection was achieved in the single case who underwent en bloc EMR, whereas it was not assessable in the case of piecemeal resections. One self-limiting bleeding was observed. The use of ORISE gel allows a well-tolerated and rapid performance of EMR of large colonic LSTs even at the time of index colonoscopy. In our opinion, in these specific situations, the use of viscous solutions is advisable and also affordable.

Clinical characteristics of non-ampullary duodenal polyps in the elderly and the outcomes of endoscopic mucosal resection.

At present, there are no reports on non-ampullary polyps of the duodenum (NAPDs) in the elderly. The aim of this study was to analyze the clinicopathological features of NAPDs in elderly and non-elderly patients to explore the efficacy and safety of endoscopic mucosal resection (EMR) of NAPDs in the elderly.A total of 110 patients underwent EMR of NAPDs between April 2016 and December 2019. The shape, location, size, postoperative complications, and histopathological types of NAPDs were compared between the elderly group (n = 44) and the non-elderly group (n = 66).Sessile type was the most common form of NAPD in both groups. In the elderly group, the average size of NAPDs was 12.6 ± 3.9 mm. In the non-elderly group, NAPDs had an average size of 10.1 ± 5.8 mm. Complete EMR was performed in both groups. The postoperative complications of EMR did not significantly differ between the 2 groups. Postoperative pathological examination showed that tubular villous adenomas were more common in the elderly group than in the non-elderly group (P = .005), while tubular adenomas were more common in the non-elderly group than in the elderly group (P = .007). Of the 110 patients, 99 completed postoperative follow-up (median follow-up duration, 20.93 months). There were no residual or recurrent lesions.EMR is safe and effective for the treatment of NAPDs in elderly patients.

Acceptability of endoscopic submucosal dissection for sessile serrated lesions: comparison with non-sessile serrated lesions.

Background and study aims Sessile serrated lesions (SSL) are major precursor lesions of serrated pathway cancers, and appropriate treatment may prevent interval colorectal cancer. Studies have reported the outcomes of endoscopic mucosal resection (EMR) for SSL; however, there are insufficient reports on endoscopic submucosal dissection (ESD). We examined the characteristics and outcomes of SSL and compared them to those of non-SSL in ESD. Patients and methods We reviewed 370 consecutive cases in 322 patients who underwent colorectal ESD between January 2016 and March 2020 at our hospital. There were 267 0-IIa lesions that were stratified into 41 SSL and 226 non-SSL (intramucosal cancer, adenoma) cases. We used propensity matching to adjust for the variances in the factors affecting treatment between the SSL and non-SSL groups. Results In the baseline cases, young women and proximal colon tumor location were significantly more common in the SSL group. There were no statistically significant differences between the SSL and non-SSL groups in terms of en bloc resection rate (97.6 % vs. 99.6 %; P = 0.28), R0 resection rate (92.7 % vs. 93.4 %; P = 0.74), perforation (0 % vs. 0.9 %; P > 0.99), and postoperative bleeding (2.4 % vs. 1.8 %; P = 0.56). Thirty-eight pairs were matched using propensity score, and the median dissection speed (12 vs. 7.7 cm 2 /h; P = 0.0095) was significantly faster in the SSL than in the non-SSL group. Conclusions ESD for SSL was safely performed, and SSL was smoother to remove than non-SSL. ESD might be an acceptable endoscopic treatment option for SSL.

EMR/ESD: Techniques, Complications, and Evidence.

To discuss endoscopic resection techniques of early gastrointestinal malignancy. The review will focus on the indications and outcomes of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR is indicated for upper GI lesions less than 20mm provided they can be easily lifted and have a low risk of submucosal invasion (SMI). ESD should be considered for esophageal and gastric lesions that are bulky, show intramucosal carcinoma, or have a risk of superficial submucosal invasion. With regard to colonic polyps, EMR is acceptable for the removal of large colonic polyps using a piecemeal technique. ESD can be reserved for rectal neuroendocrine tumors, fibrotic polyps, or polyps harboring early malignancy. In selected cases, particularly in lesions less than 2cm in size, EMR can be safe and effective. For larger lesions or lesions with submucosal invasion, ESD is effective and curative. Choosing the best approach can be tailored for each patient depending on lesion size, pathology, and availability of local expertise.

Impact of observational training on endoscopic mucosal resection outcomes and competency for large colorectal polyps: single endoscopist experience.

Background and study aims Endoscopic mucosal resection (EMR) is standard treatment for large colorectal polyps. However, it is a specialized technique with limited data on the effectiveness of training methods to acquire this skill. The aim of this study was to evaluate the impact of observational training on EMR outcomes and competency in an early-stage endoscopist. Patients and methods A single endoscopist completed comprehensive EMR training, which included knowledge acquisition and direct observation of EMR cases, and proctored supervision, during the third year of gastroenterology fellowship. After training, EMR was independently attempted on 142 consecutive, large (i. e., ≥ 20 mm), non-pedunculated colorectal polyps between July 2014 and December 2017 (mean age 61.7 years; mean polyp size 30.4 mm; en-bloc resection 55 %). Surveillance colonoscopy for evaluation of residual neoplasia was available for 86 % of the cases. Three primary outcomes were evaluated: endoscopic assessment of complete resection, rate of adverse events (AEs), and rate of residual neoplasia on surveillance colonoscopy. Results Complete endoscopic resection was achieved in 93 % of cases, the rates of AEs and residual neoplasia were 7.8 % and 7.3 %, respectively. The rate of complete resection remained stable (at 85 % or greater) with increasing experience while rates of AEs and residual neoplasia peaked and decreased after 60 cases. Conclusions An early-stage endoscopist can acquire the skills to perform effective EMR after completing observational training. At least 60 independent EMRs for large colorectal polyps were required to achieve a plateau for clinically meaningful outcomes.

Tu2041 – The Outcome of Endoscopic Mucosal Resection of Cecal Polyps Involving the Appendiceal Orifice

Tu2041 – The Outcome of Endoscopic Mucosal Resection of Cecal Polyps Involving the Appendiceal Orifice

Effect of time of day and daily endoscopic workload on outcomes of endoscopic mucosal resection for large sessile colon polyps.

Endoscopic mucosal resection of large non-pedunculated colon polyps is challenging. To determine if the time of day or daily endoscopic workload play a role in outcomes of endoscopic mucosal resection for large non-pedunculated colon polyps greater than 20 mm. This is a retrospective study of patients who underwent endoscopic mucosal resection of large non-pedunculated colon polyps. The time of day and endoscopic workload were compared across the following outcomes: the rate of complete resection of the polyp, the rate of referral for surgery, and the rate of residual neoplasia on follow-up. One hundred and three endoscopic mucosal resection procedures were performed. There were no differences in the rates of complete resection (80.8% vs. 70.0%; P = 0.25), the need for surgery (27.4% vs. 33.3%; P = 0.55), and rate of residual neoplasia (24.5% vs. 50.0%; P = 0.07) when comparing the time of day. Colon polyps greater than 40 mm were less likely to be completely resected versus polyps sized 20-39 mm (56.8% vs. 91.9%; P < 0.001). In cases with no residual neoplasia on follow-up, the mean duration for the index procedure was 45.6 minutes versus 60.7 minutes when there was residual neoplasia (P < 0.01). The time of day and endoscopic workload does not affect outcomes for endoscopic mucosal resection of large non-pedunculated colon polyps, but the size of large non-pedunculated colon polyps and resection times do.

Treatment Results of Endoscopic Mucosal Resection with a Ligation Device for Duodenal Neuroendocrine Tumors.

Objective The vertical margin of neuroendocrine tumors (NETs) removed by endoscopic mucosal resection (EMR) is often tumor-positive. We examine the treatment results of endoscopic mucosal resection with a ligation device (EMR-L) for the removal of duodenal NETs located in the submucosal layer without metastasis. EMR-L can be performed with less technical skill, and the ligation device reduces the rate of positive vertical margin. Methods Ten consecutive patients with 10 duodenal NETs resected by EMR-L were enrolled. All of the lesions were located in the submucosal layer, were assessed to be free of metastasis, and were confirmed to be NETs pathologically by an endoscopic biopsy. The endoscopic results, pathological results, and prognosis were all examined. Results The en bloc resection rate and endoscopic complete resection rate were both 100%. Complete resection was achieved pathologically in 7 lesions (70.0%). The vertical margins were negative in all cases. Lymphatic vessel invasion was observed in three patients, all of whom underwent additional surgery with lymph node dissection (one of them also exhibited blood vessel invasion and a positive horizontal margin). No evidence of residual tumors or lymph node metastasis was observed in any of the patients. No recurrence was observed in any of the 10 patients (mean follow-up period: 18.6 months). One patient (10.0%) experienced intraoperative bleeding. Perforation occurred in 1 patient (10.0%), but the condition was managed well by conservative therapy. Conclusion EMR-L was an acceptable method for endoscopically resecting submucosal duodenal NETs, and the NETs resected by EMR-L were tumor-negative in the vertical margins.