Endoscopic Mucosal Resection Procedures Research Articles

Management of delayed bleeding after endoscopic mucosal resection of large colorectal polyps: a retrospective multi-center cohort study

Background and study aims Delayed bleeding (DB) is the most frequent major adverse event after endoscopic mucosal resection (EMR) of large non-pedunculated colorectal polyps (LNPCPs). Evidence-based guidelines for management of DB are lacking. We aimed to evaluate the clinical presentation, treatment and outcome of patients with DB and to determine factors associated with hemostatic therapy. Patients and methods Patients with DB were identified by analyzing all consecutive EMR procedures for LNPCPs (≥ 2 cm) from one academic center (2012–2017) and seven regional hospitals (2015–2017). DB was defined as any postprocedural bleeding necessitating emergency department presentation, hospitalization or reintervention. Outcome of DB was assessed for three clinical scenarios: continued bleeding (CB), spontaneous resolution without recurrent bleeding during 24 hours observation (SR), and recurrent bleeding (RB). Variables associated with hemostatic therapy were analyzed using logistic regression. Results DB occurred after 42/542 (7.7 %) EMR procedures and re-colonoscopy was performed in 30 patients (72 %). Re-colonoscopy and hemostatic therapy rates were 92 % and 75 % for CB (n = 24), 25 % and 8 % for SR (n = 12), and 83 % and 67 % for RB (n = 6), respectively. Frequent hematochezia (≥ hourly) was the only factor significantly associated with hemostatic therapy (RR 2.23, p = 0.01). Re-bleeding after endoscopic hemostatic therapy occurred in 3/22 (13.6 %) patients. Conclusion Ongoing or recurrent hematochezia is associated with a high rate of hemostatic therapy, warranting re-colonoscopy in these patients. A conservative approach is justified when bleeding spontaneously settles, and without recurrent hematochezia during 24 hours observation patients can be safely discharged without endoscopic re-examination.

A80 ADVANCED ENDOSCOPIC RESECTION OF LARGE POLYPS & EARLY NEOPLASIA: OUTCOMES OF ENDOSCOPIC MUCOSAL RESECTION IN BRITISH COLUMBIA

Abstract Background Recent advances have resulted in a new technique termed endoscopic mucosal resection (EMR). This procedure has been successful at removing large or complex polyps and achieving remission rates comparable to surgery. EMR can also be used to remove early, non-metastatic cancer and they are less invasive than surgery. However, they have been associated with their own complications, most serious of which being perforation. This procedure has recently become available in British Columbia for resection of both complex polyps and early established cancers in the colon. Aims Here we present patient outcomes of EMR procedures for the resection of colorectal polyps in British Columbia. Methods Retrospective data were collected on all EMR procedures done in Vancouver General Hospital and St. Paul’s Hospital (Vancouver, B.C.) from October 2012 (when procedure became available) to July 2019. Inclusion criteria were all adults who had undergone EMR for resection of polyps in the colon. Exclusion criteria were patients younger than 18 or patients who had EMR that resected polyps in the upper GI tract. Patients were referred to one of two endoscopists when one or more polyps suitable for EMR were identified during colonoscopy by other gastroenterologists. Collected data included patient demographics, polyp characteristics, procedure outcome, and complications. Results There were 211 EMR procedures performed on 182 patients (48.9% male). Patient age ranged from 27 to 86 (mean = 67.1). A total of 244 colon polyps were removed with an average size of 2.91 cm and ranged from 0.8 cm to 15 cm. Resected polyps had the following distribution: ascending colon (63.5%), transverse colon (10.2%), descending colon (5.7%), sigmoid colon (15.2%), and rectum (5.3%). Of those that reported resection type, 84.2% were piecemeal and 15.8% were en bloc. 40.9% of polyps were tubulovillous adenoma, 33.2% were tubular, 16.2% were sessile serrated, 6.4% were villous, and 3.4% were adenocarcinoma. Patients from 11 of the 211 EMR cases (5.2%) experienced post-procedure bleed and 4 of these 11 patients (36.4%) had been on anti-platelet or anti-coagulants (discontinued before procedure). Overall, patients from 51 (24.2%) EMR cases were on anti-platelet or anti-coagulants. 33 cases (15.6%) had residual polyps at the resection site that required additional endoscopic resection during follow-up and 14 patients (6.6%) required surgery. None of the EMR procedures resulted in perforation. Conclusions EMR is an effective minimally-invasive procedures that can be used to remove large, complicated colonic polyps and achieve long-term remission rate. The procedure has an acceptable risk profile, with complication and re-intervention rate similar or less than other procedures used to remove large, complicated polyps. Funding Agencies None

399 Safety and Efficacy of Multiband Mucosectomy in Early Barrett's Neoplasia: A Systematic Review and Meta-Analysis

INTRODUCTION: Endoscopic mucosal resection (EMR) is treatment of choice for early Barrett’s neoplasia. Multiband mucosectomy (MBM) is a type of EMR procedure used for diagnosis and treatment of early Barrett’s neoplasia. This procedure has an advantage over cap-resection as it does not require submucosal lifting. We performed systematic review and meta-analysis to compare the overall safety and efficacy of this procedure for early Barrett’s neoplasia. METHODS: We conducted a comprehensive search of multiple electronic databases and conference proceedings including PubMed, EMBASE, Web of Science databases, Google Scholar and manual search of references (from inception through May 2019) to identify the studies reporting use of MBM for early Barrett’s neoplasia. The primary outcome was to evaluate the technical success of the procedure which was defined as complete endoscopic resection of a delineated focal lesion. The secondary outcome was to study overall, early and delayed adverse events related to the procedure. The meta-analysis was performed using Der Simonian and Laird random effect model. RESULTS: 15 studies reporting on 1197 patients with 1487 lesions were included. Majority of the patient population were males (80.8%), with mean age of 64 years. The pooled technical success rates were 99.1% (95% CI 96.76-100, I2 = 81.51) and the total early adverse event rates were 5.87% (95% CI 2.61-10.02, I2 = 78.26). The most common early and delayed adverse events were bleeding (5.09%; 95% CI 1.97-9.19, I2 = 79.59) and strictures (10.99%; 95% CI 5.67-17.53, I2 = 86.84) respectively. Total 5 perforations were reported in our patient population. The mean procedure time was 23.3 min reported in six studies. Significant heterogeneity was noted in in our meta-analysis. CONCLUSION: Multiband mucosectomy is a safe alternative procedure to endoscopic cap resection for the treatment of early Barrett’s neoplasia with high technical success and lower adverse events. Further large multicenter randomized controlled trials are needed for further validation of our findings.

229 Assessing Varying Techniques of Colonic Endoscopic Mucosal Resection and Subsequent Residual Adenoma at 6-Month Follow-Up

INTRODUCTION: Local recurrence at colonic endoscopic mucosal resection (EMR) sites of medium to large polyps is common at first follow-up (∼10–30%). Extended edge resection has not shown a benefit of reducing this rate; however, edge ablation with snare tip soft coagulation has shown reduced local recurrence. Hybrid argon plasma coagulation (APC) is a novel technique, which can be used to treat microscopic residual disease to prevent local recurrence at follow-up surveillance colonoscopy. This study aims to evaluate if treating both the edges and base of an EMR site with a novel technique, hybrid APC, can reduce the rate of local recurrence at 6-month follow-up versus standard EMR assessing a single endoscopist. METHODS: This is a single center retrospective case series of all colonic EMRs with 6-month surveillance performed by a single endoscopist at a tertiary care center using both standard EMR and hybrid APC assisted EMR from May 2018 to May 2019. The main outcome measure was recurrence of precancerous polyp at prior EMR site at 6-month surveillance colonoscopy. Secondary outcome measures were the rate of procedure associated complications, including post-polypectomy bleeding and post-polypectomy syndrome. RESULTS: A total of 84 EMRs, 38 utilized hAPC, were performed from in the study period. 25 patients (mean age: 65.4 years, 48% men) with 30 polyps were included who completed surveillance colonoscopy after 6 months to evaluate for recurrence (Table 1). The average resected polyp size was 32 mm. Residual polyp recurrence occurred at 4 prior EMR sites (13.3%), with all of the recurrences occurring in patients who underwent standard EMR (100%). There was no recurrence of residual polyps in patients treated with hAPC assisted EMR. Further, 4 patients (15.4%) experienced post-polypectomy bleeding complications within 6 months, with all complications associated with patients treated with standard EMR (Table 2). There was a statistically non-significant trend toward higher recurrence and complication rate in patients treated with standard EMR compared to hAPC assisted EMR. CONCLUSION: In this retrospective study of colonic EMRs, the use of hAPC at initial EMR was associated with decreased local recurrence rate of precancerous tissue at EMR sites and rate of early complications. The findings of this early retrospective study warrant further studies to determine the efficacy of hAPC in reducing the recurrence rate after 6 months and how it compares to standard EMR procedure with snare tip soft coagulation.

Endoscopic resection for superficial hypopharyngeal/laryngeal cancer and clinical pathway options

AbstractA 57‐year‐old male suffered from a metachronous squamous cell carcinoma of the larynx and refused surgical intervention. Instead, the patient opted for endoscopic mucosal resection with a cap‐fitted endoscope, a delicate procedure of endoscopic mucosal resection using a cap‐fitted endoscope, to effectively treat his small supraglottic cancer. A 3‐year follow up demonstrated no signs of tumor recurrence.

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.

Comparison of two multiband mucosectomy devices for endoscopic resection of Barrett\u2019s esophagus-related neoplasia

BackgroundEsophageal adenocarcinoma carries a poor prognosis and therefore treatment of early neoplasia arising in the precursor condition Barrett’s esophagus (BE) is desirable. Visible lesions arising in BE need endoscopic mucosal resection for accurate staging and removal. Resection modalities include a cap-based system with snare and custom-made multiband mucosectomy (MBM) devices (Duette, Cook Medical Ltd). A new MBM device has recently become available (Captivator, Boston Scientific Ltd).ObjectivesA retrospective pilot study to compare the efficacy, safety, specimen size and histology of endoscopic mucosal resection (EMR) specimens resected with two MBM devices (Cook Duette and Boston Captivator) in treatment naive patients undergoing endoscopic therapy for BE neoplasia.MethodsConsecutive EMR procedures carried out by a single experienced endoscopist were analysed. All visible lesions were marked and resected using one of the two MBM devices. All resected specimens were analysed by the same two experienced pathologists. The resected specimens in both groups were analysed for maximum diameter, minimum diameter, surface area and depth.ResultsTwenty consecutive patients were analysed (18M + 2F; mean age 74) in the Duette group and 20 (17M + 3F; mean age 72) in the Captivator group. A total of 58 specimens were resected in the Duette and 63 in the Captivator group. Min diameter, max diameter, surface area and depth of the ER specimens resected by the Captivator device were significantly larger than that by the Duette device [min diameter 9.89 mm vs 9.07 mm (p = 0.019); max diameter: 13.54 mm vs 12.38 mm (p = 0.024); surface area: 135.40 mm2 vs 113.89 mm2 (p = 0.005); depth 3.71 mm vs 2.89 (p = 0.001)].ConclusionsThese two MBM devices showed equivalent efficacy and safety outcomes, but the EMR Captivator device resected specimens with a larger area in the esophagus when compared with the Duette device. A possible advantage of this is in situations where en bloc resections with fewer EMRs are desirable for larger lesions.

Clinical outcomes of endoscopic mucosal resection for rectal neuroendocrine tumor

BackgroundThe incidence of rectal neuroendocrine tumors (NETs) is rapidly increasing because of the frequent use of endoscopic screening for colorectal cancers. However, the clinical outcomes of endoscopic resection for rectal NETs are still unclear. The aim of this study was to assess the rates of histologically complete resection (H-CR) and recurrence after endoscopic mucosal resection (EMR) for rectal NETs.MethodsA retrospective analysis was performed on patients who underwent EMR for rectal NETs between January 2002 and March 2015 at Seoul National University Hospital. Primary outcomes were H-CR and recurrence rates after endoscopic resection. H-CR was defined as the absence of tumor invasion in the lateral and deep margins of resected specimens.ResultsAmong 277 patients, 243 (88%) were treated with conventional EMR, 23 (8%) with EMR using a dual-channel endoscope, and 11 (4%) with EMR after precutting. The median tumor size was 4.96 mm (range, 1–22) in diameter, and 264 (95%) lesions were confined to the mucosa and submucosal layer. The en-bloc resection rate was 99% and all patients achieved endoscopically complete resection. The H-CR rates were 75, 74, and 73% for conventional EMR, EMR using a dual-channel endoscope, and EMR after precutting, respectively. Multivariate analysis showed that H-CR was associated with tumor size regardless of endoscopic treatment modalities (p = 0.023). Of the 277 patients, 183 (66%) underwent at least 1 endoscopic follow-up. Three (2%) of these 183 patients had tumor recurrence, which was diagnosed at a median of 62.5 months (range 19–98) after endoscopic resection. There was 1 case of disease-related death, which occurred 167 months after endoscopic treatment because of bone marrow failure that resulted from tumor metastasis.ConclusionsAlthough the en-bloc resection rate was 99% in rectal NETs, H-CR rates were 72–74% for various EMR procedures. H-CR may be associated with tumor size regardless of endoscopic treatment modalities.

Mo1151 EFFECT OF ENDOSCOPIST FATIGUE IN RELATION TO ENDOSCOPIC MUCOSAL RESECTION OF LARGE COLON POLYPS

Endoscopic mucosal resection (EMR) of large colon polyps is technically challenging and therefore often performed by endoscopists with significant experience in this procedure. It is not known if endoscopist fatigue influences the success of colon EMR for large colon polyps. The primary objective of our study is to assess whether procedural success of colon EMR is affected by endoscopist fatigue or time of day when colon EMR is performed. We conducted a retrospective review of all colon EMR procedures performed by four therapeutic endoscopists at two academic tertiary care hospitals between 1/1/2015 – 12/31/2016. Patients included for this review had colon polyps > 20 mm that were removed with injection-lift EMR technique. Technical success was defined as endoscopist assessment of complete resection of the polyp. All patients for whom follow-up information was available were assessed for residual neoplasia on follow-up colonoscopy. We assessed whether endoscopist fatigue as measured by: afternoon versus morning, number of endoscopic procedures performed before the procedure under consideration, including adjustment for procedure complexity and the total procedure related RVUs had an impact on the technical success of the procedure or the rate of residual neoplasia. In order to examine these fatigue measures we stratified the cases under review into quartiles. Quartile 1 represents the colon EMR cases with fewest preceding cases, while quartile 4 represents colon EMR cases with the largest number of preceding cases. A total of 154 patients underwent colonoscopy to resect 170 large colon polyps by EMR technique. Overall, 87.7% of the lesions were removed successfully. 21 lesions could not be removed endoscopically. Follow-up information was available for 68.3% of patients. 28 patients underwent surgery (14 for invasive carcinoma, 3 for high grade dysplasia, 11 for unresectable lesions). Of 75 patients who underwent successful colon EMR and had follow-up colonoscopy, 80% had no evidence of residual neoplasia. When assessing endoscopist fatigue by total number of procedures, number of procedures adjusted for complexity and total procedure-related RVUs prior to performing colon EMR, no effect was found in relation to technical success or rates of residual neoplasia on follow-up. There appeared to be a trend towards lower rate of technical success and a higher rate of residual neoplasia for colon EMR procedures performed in the afternoon versus the morning, however this difference was not statistically significant. We conducted similar analysis for each endoscopist individually with the same findings. Endoscopist fatigue did not have a significant effect on the technical success of colon EMR, nor did it adversely impact the rate of residual neoplasia on follow-up colonoscopy.Tabled 1Association between endoscopist fatigue and colon EMR outcome measuresFatigue measureTechnical successResidual neoplasia rateStart timeMorning exam89.5% (referant)20.4% (referent)Afternoon exam83.0% (p=0.25)34.8% (p=0.18)Raw fatigue scoreQuartile 192.7% (referent)25.0% (referent)Quartile 284.4% (p = 0.27)32.1% (p=0.62)Quartile 381.6% (p= 0.14)30.8% (p=0.73)Quartile 490.2% (p=0.69)15.8 % (p=0.50)Consensus fatigue scoreQuartile 192.7% (referent)25.0% (referent)Quartile 281.6% (p=0.15)26.3% (p=0.93)Quartile 382.5% (p =0.18)30.0% (p=0.74)Quartile 490.9% (p=0.77)13.6% (p=0.38)RVU fatigue scoreQuartile 192.7% (referent)25.0% (referent)Quartile 280.5% (p=0.12)26.3% (p=0.93)Quartile 380.5% (p=0.12)36.8% (p=0.43)Quartile 495.0% (p=0.67)15.8% (p=0.48) Open table in a new tab

Size of colorectal polyps determines time taken to remove them endoscopically.

Background an study aims Polypectomy and endoscopic mucosal resection (EMR) are effective and safe ways of removing polyps from the colon at endoscopy. Guidelines exist for advising the time allocation for diagnostic endoscopy but not for polypectomy and EMR. The aim of this study was to identify if time allocated for polypectomy and EMR at planned therapeutic lists in our endoscopy unit is sufficient for procedures to be carried out. We also wanted to identify factors that might be associated with procedures taking longer than the allocated time and to identify factors that might predict duration of these procedures. Patients and methods A retrospective case study of planned 100 lower gastrointestinal EMR and polypectomy procedures at colonoscopy and sigmoidoscopy was performed and analyzed with quantitative analysis. Results The mean actual procedural time (APT) for 100 procedures was 52 minutes and the mean allocated time (AT) was 43.05 minutes. Hence the mean APT was 9 minutes longer than the mean AT. Factors that were significantly associated with procedures taking longer than the allocated time were patient age ( P = 0.029) and polyp size ( P = 0.005). Factors that significant changed the actual procedure time were patient age ( P = 0.018), morphology ( P = 0.002) and polyp size ( P < 0.001). Procedures involving flat and lateral spreading tumor (LST) type polyps took longer than the protruding ones. On multivariate analysis, polyp size was the only factor that associated with actual procedure time. Number of polyps, quality of bowel preparation, and distance of polyp from insertion did significantly change procedure duration. Conclusion Factors that significantly contribute to duration of polypectomy and EMR at lower gastrointestinal endoscopy include patient age and polyp size and morphology on univariate analysis, with polyp size being the factor with a significant association on multivariate analysis. We recommend that endoscopy units take these factors into consideration locally when allocating time for these procedures to be safe and effective.

The occurrence and characteristics of endoscopically unexpected malignant degeneration in large rectal adenomas

Large non-pedunculated rectal polyps are most commonly resected by endoscopic mucosal resection (EMR) or transanal endoscopic microsurgery (TEM). Despite pre-procedural diagnostics, unexpected rectal cancer is incidentally encountered within the resected specimen. This study aimed to compare the diagnostic assessment and procedural characteristics of lesions with and without unexpected submucosal invasion. A post-hoc analysis of a multicenter randomized trial (TREND study) was performed in which patients with a non-pedunculated rectal polyp of≥3 cm without endoscopic suspicion of invasive growth were randomized between EMR and TEM. Unexpected rectal cancer was detected in 13% (27/203) of patients; 15 after EMR and 12 after TEM. Most consisted of low-risk T1 cancers (78%, n= 18). There were no differences in the diagnostic assessment between lesions with and without unexpected submucosal invasion. Diagnostic biopsies revealed similar rates of high-grade dysplasia (28% [7/25] vs 18% [26/144]). When compared with EMR of adenomas, EMR procedures of unexpected cancers had a lower success rate of submucosal lifting (60% vs 93%, P< .001), were more often assessed as endoscopically incomplete (33% vs 10%, P= .01), and were more frequently terminated prematurely (60% vs 8%, P= .001). Diagnostic assessment of large non-pedunculated rectal polyps revealed similar characteristics between unexpected cancers and adenomas. Unexpected cancers during EMR were non-lifting in 40%, endoscopically assessed as incomplete in 33%, and terminated prematurely in 60%. In treatment-naive patients, these factors should raise suspicion of malignancy and need discussion in a multidisciplinary team meeting for decision on further treatment strategies.

Risk Factors for Delayed Hemorrhage After Colonic Endoscopic Mucosal Resection (EMR) Focused on Patients who did not Receive Antithrombotic Therapy: A Retrospective Pilot Chart Review

Introduction: Antithrombotic agents are one of major risk factors for delayed hemorrhage after colonic EMR. Whereas the patients without antithrombotic therapy can be performed colonic EMR relatively safe, there are several risks to receive colonic EMR. The aim of present study was to evaluate the risk factors of the delayed hemorrhage after colonic EMR in patients without antithrombotic therapy. Methods: The present study included 995 patients with colonic EMR from January 2013 to December 2016 in Saga Medical Centre Koseikan. The patients who received antithrombotic therapy were excluded from the study. The risk factors were evaluated regarding the patient-characteristics, the lesion-characteristics, and prevented hemoclips. Delayed hemorrhage was defined that the emergency endoscopic hemostasis was applied for bleeding more than 24 h after the EMR procedure. Results: Totally, 2,034 polyps of 995 patients were evaluated in the present study. The average of age was 68.0 years old and the average polyp size was 7.6 mm. Delayed hemorrhage occurred in 14 patients (1.4%). Multivariate analysis indicated that delayed hemorrhage occurred more frequently in the young patients (age <70 years old, P<0.01), and in the large polyp (size >10mm, P=0.01). Prevented hemoclips were applied for the 284 patients (28.5%), and the clips were not statistically effective for delayed bleeding. Conclusion: The present pilot retrospective chart review suggested that the relatively young age (age <70 years old) and the relatively large polyps (size >10 mm) might be risks for the patients without antithrombotic therapy, which warrant a further clinical trial with multicenter study in Japan.

Efficacy and Safety of Endoscopic Mucosal Resection for Esophageal Lesions in a Private Community Practice Setting

Introduction: Endoscopic mucosal resection (EMR) can be performed for a variety of esophageal lesions. EMR offers an effective, safe and minimally invasive alternative to the conventional surgical approach and in conjunction with radiofrequency ablation (RFA), has virtually eliminated esophagectomy for patients with dysplastic Barrett's and intra-mucosal cancer (IMC). However, in a community hospital setting endoscopists mostly had avoided it due to fear of complications, especially perforation. The aim of this study is to review our results of EMR for esophageal lesions with respect to efficacy and safety to better define its utility in a private community practice setting. Methods: This is a retrospective analysis of patients who underwent esophageal EMR between Jan 1st 2014 and July 31st 2016 at our center. Patient's demographics, procedural details, complications and histopathology were analyzed and reported. Results: A total of 115 patients underwent 140 EMR procedures (Tables 1 and 2). The mean age was 66.5 ± 11.9 years and 77% were males. The majority of the EMR were performed in the setting of nodular Barrett's with or without dysplasia (48.6%) and adenocarcinoma (29.3%). EMR was applied to a variety of other mucosal lesions in the esophagus as well. Multiband mucosectomy (MBM) was utilized in the majority of procedures (94.3%). In patients with Barrett's esophagus, EMR in combination with ablation was able to eradicate dysplasia or IMC in 28/32 patients (87.5%). Intra-procedural bleeding occurred in 42 cases (30%), but immediate hemostasis was achieved in all and in majority with the tip of the snare with soft coagulation current. Two patients (1.74%) developed delayed bleeding and one required endoscopy to control bleeding successfully. Four patients (3.7%) with more than 75% circumferential resections, developed strictures, two of them required dilation. There was no case of perforation. Mean operative time was 34.5 ± 14.6 minutes.Table: Table. Summary of Patients' DemographicTable: Table. Histopathological Characteristics of Lesions and Procedure DetailsConclusion: Our results are comparable to previous studies investigating the eradication of Barrett's esophagus with dysplasia and rate of stricture development. Our data shows that EMR is safe and effective diagnostic and therapeutic tool for advanced Barrett's, early esophageal cancer and a variety of other esophageal lesions.Figure: The schematic shows the basic steps of Endoscopic Mucosal Resection.Figure: The images shows different steps involved in Endoscopic Mucosal Resection of the esophageal nodules.

Impact of endoscopic mucosal resection in the histologic reclassification and treatment of Barrett’s esophagus associated dysplasia

Introduction and aims. In selected patients, endoscopic mucosal resection (EMR) is a valuable tool for diagnosis and treatment of Barrett's esophagus (BE). Currently, there is few available information regarding the reclassification of histological diagnosis in BE associated focal lesions. The aim was to evaluate the reclassification of histological diagnosis post-EMR, in patients with BE with biopsy proven dysplasia. Material and methods. This is a retrospective and descriptive study. We included patients with BE from January 2002-december 2013, in whom EMR was performed and had a previous biopsy with either low grade dysplasia (LGD), high grade dysplasia (HGD) or intramucosal carcinoma (IMC).EMR was performed by either the cap technique or by using the multi-band ligator technique. Results. We analyzed 41 specimens obtained in 19 EMR procedures performed in 11 patients. When pre and post-EMR diagnosis were evaluated, there was a reclassification in histological diagnosis in 7 of 11 (63%) patients (downstaging occurred in 5 and upstaging occurred in 2 patients). The global follow-up time was 45 (3-95) months. Nine patients (81.8%) received endoscopic eradication therapy without recurrence in the follow up. There were no procedure related complications. Conclusions. EMR conditions a significant change in histological diagnosis in BE with dysplasia patients.

PTU-008 Are Patients Undergoing Endoscopic Mucosal Resection for Colorectal Lesions Appropriately Assessed and Referred Prior to Their Procedure

Introduction Endoscopic Mucosal Resection (EMR) has been developed for minimally invasive endoscopic removal of large benign and early malignant lesions. Before carrying out colorectal EMR, it is important to characterise the lesion for removal distinguishing between adenoma and adenocarcinoma and the marginal demarcation of the lesion. There are a number of tools an endoscopist can use to characterise a lesion such as observation (e.g. lesion colour, presence of depression and use of the Paris classification) as well as more advanced techniques such as chromo-endoscopic observation (using Kudo classification) and then check for non-lifting sign in presumed colorectal cancers Methods A single centre, retrospective analysis in a large London NHS Foundation Hospital was performed. All patients undergoing EMR were identified using Unisoft Endoscopy reporting software across a period of 12 months (Jan 2015-Jan2016). Data was collected regarding the referral, EMR procedure and the patients’ histological diagnosis. Results 32 patients were referred and underwent EMR with colorectal lesions greater then 2 cm in size. 23 lesions were accurately described in terms of size. 17 lesions were only described in terms of polyp, with no further distinguishing features. Only 9 of the lesions were commented on with regards to Pitt pattern or Paris classification. 3 lesions were identified as cancerous at the time of endoscopy with only one checked for lift sign. 13 lesions were biopsied, prior to EMR. 6 lesions were rectal and only 8 out of the remaining lesions were tattooed. In referral of the lesions 7 had specified the number of units required for the EMR procedure, 3 were referred for MDT discussion the rest had no further details. Conclusion Our case series shows a wide variation in practice in regards to lesion description which can have detrimental effects on patient care. A large number of polyps referrals to EMR are not clearly described in terms of Paris or Kudo classification and the absence of the non-lifting sign. The planning of EMR could be made easier if the pre-EMR assessment included size of the lesion, and clear description with regards to pit pattern and Paris classification. In addition allowing adequate time can be difficulty without a clear lesion description. Regular auditing and presentation go some way to improving practice in a department but endoscopists can come from different departments, be locums or endoscopy can be out sourced. Our opinion would be to ensure that cues are placed in the reporting software to enable accurate assessment and management of lesion considered for EMR as an alternative to EMR endoscopist having to repeat the colonoscopy to assess the lesion prior to scheduling the EMR with appropriate length of time to perform to the procedure. Disclosure of Interest None Declared

A laser-induced pulsed water jet for layer-selective submucosal dissection of the esophagus.

Background and aims: Conventional water jet devices have been used for injecting fluid to lift up lesions during endoscopic submucosal dissection or endoscopic mucosal resection procedures. However, these devices cannot dissect the submucosal layer effectively. Here we aim to elucidate the dissection capability of a laser-induced pulsed water jet and to clarify the mechanism of dissection with layer selectivity. Materials (Subjects) and methods: Pulsed water jets were ejected from a stainless nozzle by accelerating saline using the energy of a pulsed holmium: yttrium-aluminum-garnet laser. The impact force (strength) of the jet was evaluated using a force meter. Injection of the pulsed jet into the submucosal layer was documented by high-speed imaging. The physical properties of the swine esophagus were evaluated by measuring the breaking strength. Submucosal dissection of the swine esophagus was performed and the resection bed was evaluated histologically. Results: Submucosal dissection of the esophagus was accomplished at an impact force of 1.11-1.47 N/pulse (laser energy: 1.1-1.5 J/pulse; standoff distance: 60 mm). Histological specimens showed clear dissection at the submucosal layer without thermal injury. The mean static breaking strength of the submucosa (0.11 ± 0.04 MPa) was significantly lower than that of the mucosa (1.32 ± 0.18 MPa), and propria muscle (1.45 ± 0.16 MPa). Conclusions: The pulsed water jet device showed potential for achieving selective submucosal dissection. It could achieve mucosal, submucosal, and muscle layer selectivity owing to the varied breaking strengths.

Underwater Endoscopic Mucosal Resection: Safe and Effective?

Introduction: Techniques for endoscopic removal of colonic polyps has rapidly expanded in recent years. Endoscopic mucosal resection (EMR) involving saline injection to safely remove large and sessile polyps has been the current standard of care. Recently a novel technique known as underwater endoscopic mucosal resection (UWEMR) has shown promise. UWEMR involves complete water immersion of polyps and snare resection without submucosal injection. A few small studies have shown this technique to be effective in large polyp removal with minimal training and short learning curve. This study set out to further validate the success and safety of this novel endoscopic technique for polyp removal. Methods: We performed a retrospective review of underwater EMR procedures performed by 2 endoscopists at a tertiary care center over a 2 year period. The main outcome was technical success defined as complete resection without need for conventional saline injection technique. Secondary outcomes included need for additional intervention for polyp removal, immediate complications (less than 24 hours), delayed complications (greater than 24 hours). Results: In a total of 26 patients (11 males, mean age 60.7 years), 32 polyps were removed over the study period. The mean polyp size was 23.4 mm (range 5mm-50mm) with pathology revealing 62.5% tubular adenoma, 12.5% tubulovillous adenoma, 12.5% sessile serrated adenomas, 6.3% hyperplastic and 1 case of adenocarcinoma. 31 of 32 polyps (96.9%) were removed using the UWEMR technique without conversion to conventional EMR. There were no immediate complications. There were 2 cases (7.6%) of delayed complication of hematochezia requiring repeat colonoscopy and hemostasis. One occurred in a case of invasive adenocarcinoma and the other in a patient with Ehlers-Danlos. No other complications were noted. Conclusion: Underwater EMR is an emerging technique that is being broadly investigated. This study supports the existing literature demonstrating technical success of this endoscopic intervention. Risk of delayed bleeding may be slightly higher with this technique than conventional EMR. Whether this is due to a learning curve not previously seen, individual patient factors, or safety of the technique itself is not clear from our results. Further prospective study is warranted to assure its safety and potential for widespread adoption.

Antimicrobial prophylaxis in patients with colorectal lesions undergoing endoscopic resection.

To investigate the effect of prophylaxis with antibiotics on clinical adverse events in patients who underwent endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) for colorectal lesions. From June 2011 to December 2013, a total of 428 patients were enrolled into the study, of which 214 patients admitted to hospital underwent EMR or ESD procedures. These patients were randomized to an antibiotic group, in which patients were given cefuroxime 1.5 g iv half an hour before and 6 h after surgery respectively, and a control group, in which patients were not given any antibiotic. A further 214 outpatients with small polyps treated by polypectomy were compared with controls that were matched by age and gender, and operations were performed as outpatient surgery. Recorded patient parameters were demographics, characteristics of lesions and treatment modality, and the size of the wound area. The primary outcome measures were clinical adverse events, including abdominal pain, diarrhea, hemotachezia, and fever. Secondary outcome measures were white blood cell count, C-reactive protein and blood culture. Additionlly, the relationship between the size of the wound area and clinical adverse events was analyzed. A total of 409 patients were enrolled in this study, with 107 patients in the control group, 107 patients in the antibiotic group, and another 195 cases in the follow-up outpatient group. The patients' demographic characteristics, including age, gender, characteristics of lesions, treatment modality, and the size of the wound area were similar between the 2 groups. The rates of adverse events in the antibiotic group were significantly lower than in the control group: abdominal pain (2.8% vs 14.9%, P < 0.01), diarrhea (2.0% vs 9.3%, P < 0.05), and fever (0.9% vs 8.4%, P < 0.05) respectively. The levels of inflammatory markers also decreased significantly in the antibiotic group compared with the control group: leukocytosis (2.0% vs 11.2%, P < 0.01), and C-reactive protein (2.0% vs 10.7%, P < 0.05). Additionally, clinical adverse events were related to the size of the surgical wound area. When the surgical wound area was larger than 10 mm × 10 mm, there were more clinical adverse events. Clinical adverse events are not uncommon after EMR or ESD procedures. Prophylactic antibiotics can reduce the incidence of clinical adverse events. This should be further explored.

Is the Double Channel Gastroscope Useful in Endoscopic Mucosal Resection for Large Sessile Colon Polyps?

See Use of a Double-Channel Gastroscope Reduces Procedural Time in Large Left-Sided Colonic Endoscopic Mucosal Resections by Evangelos Voudoukis, Georgios Tribonias, Aikaterini Tavernaraki, et al., on page 136-141 Most colon polyps are less than 1 cm in size. However, endoscopists often encounter large sessile colon polyps greater than 2 cm in practice. Removal of a large sessile colon polyp is difficult due to a high rate of procedure-related complications, such as bleeding and perforation. Therefore, patients with large sessile colon polyps are referred to a tertiary hospital for appropriate treatment. There are two usual endoscopic treatments for large sessile colon polyps: conventional endoscopic mucosal resection (EMR), and endoscopic submucosal dissection (ESD). ESD using various knives was initially introduced for the treatment of early gastric cancer, but has recently, been used for large sessile colon polyps. Theoretically, ESD is preferable to en bloc resection for better pathologic evaluation. However, because of high complication rates, ESD is not widely used for the treatment of large sessile colon polyps. Despite the advent of gastric ESD, piecemeal EMR is more widely used than ESD in such polyps. In Western countries, because of the technical difficulty and longer procedure time of ESD, piecemeal EMR is still the gold standard therapy for large sessile colon polyps >20 mm in diameter.1 Although many endoscopists are performing colonic EMR, little attention has been paid to reducing the procedure time, which can be a very important issue in high-volume centers. Longer procedure times may influence the work of physicians and other personnel in the endoscopy room. One study reported that the total procedure time for EMR in patients with large sessile colon polyps (2 cm or larger) averaged 51.4 minutes (standard deviation, 25.6).2 The mean size of the polyps was 34.2 mm, the perforation rate was 1.1%, and the post-EMR bleeding rate was 7.3%. Procedure time was measured from endoscope insertion to examination completion. In another large-scale study on ESD for large colon polyps, the mean procedure time was 116 minutes, with a mean tumor size of 35 mm; perforation occurred in 4.9%, and postoperative bleeding in 1.5%.3 In this issue of Clinical Endoscopy, Voudoukis et al.4 present their experience with large (>2 cm) sessile or flat left-sided colon polyp resection, focusing on the benefits of the double channel (DC) gastroscope for EMR. In their retrospective series, they compared the procedure time using a DC gastroscope to that for a standard colonoscope or gastroscope (OS). They measured the EMR procedure time from first submucosal injection to just following polyp resection. This measurement method was different from that used by other researchers. The mean procedure time differed significantly between the DC group (33±21 minutes) and the OS group (58.7±20.6 minutes, p=0.015); in the subgroup of patients with polyps larger than 40 mm, the statistical difference in the mean procedural time between the two groups was even more pronounced (p=0.004). They suggest that use of a DC gastroscope for large non-pedunculated rectosigmoid lesions significantly reduces the procedure time. A DC scope is sometimes used in a difficult colonic EMR, but is not widely used in a routine procedure. The primary technique using a DC scope is the simultaneous insertion of a forceps, which can grasp polyp tissue and pull it into position for snare polypectomy5 or EMR; endoscopists can use the injection needle and snare at the same time with the DC scope. This might reduce the total operative time, and enable endoscopists to perform procedures without interruption. Nishizawa et al.6 called it the two-sword fencing technique in ESD, which also saves the time of changing endoscopic devices. The two-sword fencing technique allows mucosal resection just after injection, before the collapse of the submucosal cushion. However, endoscopists must be careful when snare EMR using forceps, because the proper muscle is held inside the forceps. It is difficult to keep the dissection plane horizontal to the intestinal wall with ESD using a DC gastroscope. Information on use of a DC gastroscope would be useful in EMR or ESD for large sessile colon polyps. This study has several important features. It is the first study in which the authors have compared the DC scope with single channel scopes in EMR for large sessile colonic polyps. However, as the authors state in their discussion, the number of patients was too small to be able to generalize the results of the study. In addition, the authors compared the DC gastroscope with single channel scopes. Upper endoscopy and colonoscopy were included in the single channel OS scope group, and should have been compared individually with the DC gastroscope. Finally, this retrospective study was conducted by a single experienced endoscopist. The procedure time might be dependent on the features of the endoscopist. A prospective study with multiple endoscopists will be needed.

A tailored approach for endoscopic treatment of small rectal neuroendocrine tumor.

Resection of rectal neuroendocrine tumors (NETs) less than 1 cm in diameter can be performed using various endoscopic techniques. Endoscopic mucosal resection (EMR) traditionally had suboptimal complete resection rate compared to endoscopic submucosal resection with band ligation (ESMR-L). However, the previous studies did not consider the characteristics of rectal NETs. The aim of our study is to compare the efficacy of ESMR-L and EMR using tailored approach according to the characteristics of rectal NETs. 82 rectal NETs in 77 patients treated by ESMR-L (n = 48) or EMR (n = 34) between September 2007 and October 2012 were retrospectively analyzed. ESMR-L was used for flat-type tumors or tumors with non-lifting sign after submucosal injection. Conventional EMR was used for elevated-type tumors or tumors with well-lifting sign after submucosal injection. The pathological complete resection rate was higher in the ESMR-L group (45 lesions, 93.8%) compared with the EMR group (30 lesions, 88.2%); however, this difference was not significant (p = 0.441). Overall complication did not differ significantly between the ESMR-L group and the EMR group (p = 0.774). There was one case of a remnant lesion in the ESMR-L group, which was managed by EMR after circumferential pre-cutting (EMR-P), and no recurrence has been detected in either the ESMR-L or EMR group. ESMR-L and EMR procedures could have a similar excellent complete resection rate, if we select the endoscopic resection technique according to the characteristics of the small rectal NETs.