ESOPHAGUS 1 - Gastroenterology

ESOPHAGUS 1

FRIDAY, MAY 21, 2021Esophagus 1Poster

ID: 3520917ESOPHAGEAL EPIDERMOID METAPLASIA: A CASESERIES OF 40 PATIENTSAmrit K. Kamboj*, Ying Gibbens, Catherine E. Hagen,Kenneth K. Wang, Prasad G. Iyer, David A. KatzkaBackground: Esophageal epidermoid metaplasia (EM) is a rare condition sporadi-cally associated with dysplasia/esophageal squamous cell carcinoma (ESCC). Inthis study, we highlight the epidemiology, clinical course, and endoscopic and pa-thology features of esophageal EM in the largest case series reported to date.Methods: Patients diagnosed with esophageal EM at Mayo Clinic between January 1,2014 and October 31, 2020 were identified using a pathology database. Data wascollected on patient demographics, prior esophageal disease, endoscopic and pa-thology features of EM, and follow-up. Results: 40 EM cases were identified [23(58%) men, 38 (95%) Caucasian] (Table 1). The mean (SD) age at diagnosis was 66.3(11.5) years. Current or former history of tobacco (58%) or alcohol (73%) useoccurred in >50%. Seven (18%) and 5 (13%) patients had a history of oral andesophageal LP, respectively. Thirty-two (80%) patients had a history of gastro-esophageal reflux disease. Seven (18%) patients had BE (non-dysplastic 2, low-grade1, high-grade 4); 6 were treated with endoscopic resection or ablation. Eight (20%)patients had a history of ESCC and 1 (3%) had prior EAC; 5 (13%) received endo-scopic resection and 4 (10%) underwent chemoradiation. In the 9 patients with EMand history of esophageal cancer, the median (range) between diagnoses was 13 (4-124) months and 6 (67%) had EM at or near site of prior malignancy. Most patients(83%) had undergone an EGD prior to EM diagnosis at a median (range) of 5 (0-77)months prior to diagnosis. Nineteen (48%) patients had EGD within 6 months of EMdiagnosis. Two-thirds (68%) had dysphagia at time of EM diagnosis. EM was mostcommonly located in the distal 1/3 (nZ19, 48%) and middle 1/3 (nZ8, 20%)esophagus. Endoscopically, EM was characterized as having mucosal changes suchas altered texture, white plaques, keratotic patches, sloughing, granularity, nodu-larity, furrows, decreased vascularity, and lacy appearance (Figure 1). Histologicfeatures of EM were hyperkeratosis or parakeratosis and prominent granular celllayer. Two (5%) patients had dysplasia within EM at EM diagnosis. Two-thirds (65%)of patients were observed while 9 (23%) underwent endoscopic resection and 5(13%) underwent ablation without adverse effects. The median (range) follow-uptime and number of EGDs performed after EM diagnosis was 11.5 (0-72) months and2 (0-17) EGDs respectively with development of squamous dysplasia in 5 (13%)patients and ESCC in 1 (3%) patient. The incidence of squamous dysplasia and ESCCafter EM diagnosis was 10 per 100 person-years. Conclusion: Esophageal EM is apremalignant esophageal condition and is associated with multiple prior conditionsincluding LP, BE and EAC, or ESCC in roughly half the cases. Given the association ofEM with dysplasia and esophageal cancer, close follow-up or endoscopic treatmentmay be warranted.

Table 1. Epidemiology and clinical course of epidermoid metaplasia.

Figure 1. Endoscopic features of epidermoid metaplasia.

www.giejournal.org Volume 93, No. 6S : 2021 GASTROINTESTINAL ENDOSCOPY AB269

http://www.giejournal.org


ID: 3524478THE UTILITY OF FAMILY HISTORY AS A RISK FACTOR INIDENTIFYING PATIENTS WHO WOULD BENEFIT FROMSCREENING FOR BARRETT’S ESOPHAGUS ANDESOPHAGEAL ADENOCARCINOMABrendon M. O’Connell*, Erin J. Song, Brian Sullivan, Rachel Myers,Tejinder K. Rakhra-Burris, Alice Parish, Donna Niedzwiecki, R. R. Wu,Lori A. Orlando, Katherine S. GarmanBackground: Guidelines recommend different screening criteria for Barrett’s esoph-agus (BE) and esophageal adenocarcinoma (EAC) with varying emphasis on familyhistory (FHx). However, the utility of family history-based screening paradigmsversus more conventional GERD-based screening paradigms is unknown. Aim: In acohort of patients with a FHx of gastrointestinal (GI) malignancy, we aimed todetermine the number of patients who had been appropriately evaluated for BE andEAC based upon different risk factors (RFs), including FHx. We then compared theperformance of family history-based screening recommendations versus more con-ventional GERD-based screening recommendations in this population. Methods: Weperformed a secondary analysis of the IGNITE Trial, which is a multi-center studydesigned to evaluate the MeTree clinical decision support tool. MeTree is a patient-facing, web-based, FHx-driven risk assessment tool used to provide personalizedscreening recommendations to patients in the primary care setting. For trial par-ticipants found to have a FHx of GI malignancy, detailed chart review was performedto obtain baseline demographics as well as details of concomitant GERD, tobaccouse, and proton-pump inhibitor (PPi) use. All EGD reports and associated findingswere reviewed. We then compared adherence to multiple different screening stra-tegies (ACG, ASGE FHx only, ASGE GERD +1RF only, and ASGE combined) and therelative performance of each by calculating the number needed to screen (NNS) tofind one patient with BE or EAC. Results: In the IGNITE trial, there were 1,416 en-rollees at our local site, 408 of which had a FHx of GI malignancy. Seventy-fourpatients reported a FHx of esophageal cancer or BE. Our cohort was predominatelywhite (89%), female (73%), and insured (95%). Patients with GERD (58% vs. 9%,p<0.0001) or who were prescribed a PPi (73% vs. 20%, p<0.0001) were more likelyto have undergone EGD (Table 1). Rates of EGD among those eligible for screeningvaried across guidelines (ACG 64%, ASGE FHx only 31%, ASGE GERD + 1 RF only58%, and ASGE combined 48%). While many eligible patients did not receive anEGD (Table 2), GERD-based screening guidelines outperformed family history-basedscreening guidelines in those who completed endoscopy (ACG NNS 6.48, ASGE FHxonly NNS 38.91, ASGE GERD + 1RF only NNS 8.41, and ASGE combined NNS 11.07).Conclusions: GERD-based screening guidelines outperformed guidelines with astronger emphasis on FHx in a large, predominantly female cohort of patients.Nevertheless, FHx remains an important RF for BE and EAC, and these patients areless likely to receive appropriate screening. More research is needed to understandwhich RFs for BE and EAC are most salient and to investigate the utility of tools suchas MeTree, which may help identify asymptomatic patients who are at risk for BE andEAC.

Table 1. Factors associated with previous endoscopic evaluation*Prescription information not available for 2 patients

Table 2. EGD Findings of BE or EAC as stratified by different screeningcriteria.

Abstracts

AB270 GASTROINTESTINAL ENDOSCOPY Volume 93, No. 6S : 2021 www.giejournal.org



ID: 3522132FLEXIBLE ENDOSCOPIC VERSES RIGID TRANSORALTREATMENT OF ZENKER’S DIVERTICULUM: EFFICACYAND SAFETY COMPARISONRussell D. Dolan*, Thomas M. Runge, Thomas R. McCarty,Christopher C. ThompsonBackground: Zenker’s diverticula are outpouchings in the upper esophagus, result-ing from mucosal and submucosal herniation through the cricopharyngeal muscle.Associated symptoms may include halitosis, dysphagia, regurgitation, aspiration andweight loss. Compared to traditional transcervical diverticulectomy, treatment ofsymptomatic Zenker’s diverticulum via a transoral approach is a less invasive alter-native. However, direct comparisons between rigid transoral and flexible endoscopicrepair approaches are lacking. The primary study aim was to compare efficacy andsafety of flexible endoscopic versus rigid transoral Zenker’s diverticulum repair.Methods: This was a retrospective matched cohort study of patients with Zenker’sdiverticulum who underwent flexible endoscopic (FLEX) or rigid transoral (RIGID)ZD repair at two tertiary referral centers. FLEX patients were matched 1:1 to RIGIDpatients based on age and Charlson Comorbidity Index (CCI) score. Patient demo-graphics, technical success rate, clinical success rate, serious adverse event (SAE)rate, hospital length of stay (LOS), length of post-procedure liquid diet and pro-cedure duration were collected. The primary outcomes were comparison of tech-nical success, clinical success and SAE rates between groups. Secondary outcomesincluded comparisons of hospital LOS, length of post-procedure liquid diet andprocedure duration. A Fisher’s exact test was used to compare the primary out-comes and Student’s t-test was used for secondary outcome comparisons. Results: Atotal of 102 ZD patients (51 FLEX, 51 matched RIGID) were included. Mean (SD)follow-up was 1.4 (2.3) and 2.4 (3.2) years in the FLEX and RIGID groups, respec-tively. Pre-repair age, sex, CCI, diverticulum size and frequency of prior attemptedrepairs were similar between groups (Table 1). The technical success rate was similarbetween FLEX and RIGID (72.7% vs 70.7%; pZ1.0); however, the clinical successrate was significantly higher in the FLEX group (76.5% vs 45.1%; pZ0.002) and SAErate was significantly lower in the FLEX group (23.5% vs 45.1%; pZ0.008) (Table 2).FLEX patients experienced a significantly shorter hospital LOS and procedure lengthwas similar between groups. Conclusions: Endoscopic treatment of symptomaticZenker’s diverticulum with a flexible endoscopic approach is associated with asignificantly higher clinical success rate and significantly fewer serious adverseevents and shorter length of hospital stay compared to the transoral rigid approach.


ID: 3524123STUDY OF COMPLIANCE, PRACTICE PATTERNS, ANDBARRIERS REGARDING ESTABLISHED NATIONALSCREENING PROGRAMS FOR BARRETT’S ESOPHAGUSAMONG GASTROENTEROLOGY PROVIDERS:SCREEN-BEJennifer M. Kolb*, Anna Tavakkoli, Ravy K. Vajravelu, Erica Miles,Mindy L. Chen, Frank I. Scott, Gary W. Falk, Amit G. Singal, Sachin B. WaniBackground: Gastroenterology society guidelines recommend upper endoscopy toscreen for Barrett’s esophagus (BE), the only identifiable precursor lesion foresophageal adenocarcinoma (EAC). However, <10% of EACs are known to have BEprior to diagnosis. We aimed to determine gastroenterologist’s (GI) knowledge,attitudes, and potential barriers to implementing BE screening. Methods: TheSCREEN-BE study was conducted at 3 academic medical centers and 2 affiliatedcounty hospitals. We conducted a web-based survey, with questions adapted fromvalidated cancer screening-related surveys when available. Pretesting and pilottesting were performed. Survey domains included provider and practice character-istics, screening practices, perceived barriers to screening, knowledge of guidelinesas assessed by clinical vignettes, and attitudes and beliefs about screening, Results:We obtained a response rate of 65.2% (94 of 144 GI providers). Over half (59.6%)were male, and 90.4% were physicians. Nearly half of providers (48.9%) see anaverage of 2-10 patients with GERD each week, while 27.7% see 0-1 and 23.4% see11-25. Most providers reported increased likelihood of ordering BE screening inpatients with risk factors including GERD (97.9%), family history of BE/EAC (94.7%),alarm symptoms (93.6%), age (91.5%), male (90.4%), white race (88.3%), obesity(88.3%) and smoking (87.2%). Although two-thirds (69.2%) of providers recom-mended no further testing if index screening endoscopy was negative, 17% statedthey do not recommend screening for BE, 11.7% recommended a 5-year interval,1.06% recommended a 3-year interval, and 1.06% a 10-year interval for repeatscreening. Most providers did not report any barriers to BE screening; however,potential barriers included insurance coverage (22.3%), difficulty identifying at-riskpatients (18.1%), patient lack of understanding (14.9%), and competing clinical is-sues (12.8%) (Table). Most providers (72.4%) reported knowing current guidelinerecommendations, with a median guideline-concordance score for the 9 clinical vi-gnettes of 7 (IQR 6-8) (Figure). Most providers felt BE screening is their responsi-bility (89.4%). The majority of providers (62.8%) expressed interest in learning moreabout BE screening. Conclusions: Gastroenterology providers recognize key patientfactors that should prompt BE screening, routinely perform upper endoscopy for BEscreening, and report minimal barriers to BE screening. Their practice patterns arelargely concordant with guideline recommendations, although 17% state they don’trecommend screening and 14% recommend repeat screening after a negative exam.Ongoing research should address barriers to BE screening among other groups suchas primary care providers and patients and the benefits and harms of screening.Funded by the ACG Clinical Research Award 2020

Application of screening guidelines to clinical vignettes among GI pro-viders (nZ94)


Abstracts


Gastroenterology provider attitudes regarding Barrett’s esophagusscreening with upper endoscopy


ID: 3525147OUTCOMES OF PATIENTS WITH ESOPHAGEALSQUAMOUS CELL DYSPLASIA OR CARCINOMAUNDERGOING ENDOSCOPIC THERAPY IN A WESTERNPOPULATIONSiddharth Agarwal*, Lovekirat Dhaliwal, Don C. Codipilly,Ramona Lansing, Rachel E. Rhody, Kenneth K. Wang, Prasad G. IyerIntroduction: Early stage esophageal squamous carcinoma (ESCC) or squamousdysplasia (SD) can be treated with endoscopic eradication therapy (EET). Mostdata demonstrating the effectiveness of EET in this setting are from the East, givenlow incidence of ESCC and ESD in Western populations. We studied the outcomesof EET for the evaluation and treatment of ESCC and SD in a tertiary referral centerin the USA. Methods: Patients with ESCC and/or SD undergoing EET were identifiedvia an electronic search of medical records at our institution from 2010 to 2020.Medical records of these patients were reviewed and clinical, histological andendoscopic data were abstracted. Our primary outcome was the rate of completeremission of cancer (CRCa) and complete remission of dysplasia (CRD). Secondaryoutcomes were rates of complications and predictors of achieving CRCa/CRDdefined as the absence of carcinoma (CRCa) or dysplasia (CRD) on at least onesurveillance endoscopy. Survival analysis and Cox-proportional hazard models wereused to determine predictors of CRCa/CRD. Results: We included 60 patients in thestudy. Baseline demographic, clinical variables and histopathology are shown inTable 1. All procedures were performed by two endoscopists with considerableexpertise in esophageal endotherapy. Endoscopic resection in 56 revealed ESCC in46 and SD in 10 patients. 3 of these reached CRCa without need for ablation. Fourpatients were treated with ablation as the initial treatment (with RFA in 1, Cryoa-blation in 2 and PDT in 1). 49 patients continued EET: 11.7% (nZ7) had RFA, 30%(nZ18) had spray cryotherapy, 6.7% (nZ4) had balloon cryoablation and 33.3%(nZ20) had endoscopic resection. Of these 33 (67%) reached CRCa or CRD over amedian (IQR) follow up of 14.5 (6-40.5) months. The median time to CRC/CRD was9 months (IQR 4-60). Overall CRCa/CRD rates at 1 and 2 years were 55.21% and68.99%, respectively. The remaining 19 patients are still continuing EET. Three (5 %)patients underwent esophagectomy. Seven (11.7%) patients received chemoradia-tion. Complications including perforation and strictures were observed in 1 patientafter ESD(1.6%) and 5 (8.3%) of patients respectively. A positive lateral or deepmargin on resection histology was a negative predictor for achieving CRCa/CRD(Table 2). Median follow up after CRCa/CRD was 15.5 months (IQR 0-34.5). Fivepatients had a recurrence of dysplasia/cancer which could be treated endoscopically.Conclusion: ET appears to be effective in the treatment of early stage squamous cellcancer and squamous dysplasia. Negative lateral and deep margins on endoscopicresection were favorable prognostic factors in achieving CRCa/CRD. Larger studiesare needed to confirm these results in Western populations.

Table 1. Baseline characteristics of patients with ESCC or SquamousDysplasia treated endoscopically.

Table 2. Predictors of achieving histological remission with endoscopictherapy in patients with ESCC or Squamous Dysplasia.


Abstracts



ID: 3526977THE EFFECT OF ELECTROCAUTERY SETTINGS ON THELEVEL OF SUBMUCOSAL RESECTION WITH BANDMUCOSECTOMY TECHNIQUE IN THE ESOPHAGUS ANDSTOMACH: A PORCINE STUDYAndrew C. Elden*, Brianna Shinn, Jeffrey P. Baliff,Alexander Schlachterman, Christina J. Tofani, Anthony InfantolinoBackground: Endoscopic mucosal resection (EMR) has become standard of caremanagement for certain nodules and polyps, however there is a lack of uniformchoice in electrocautery settings used. As a result, we aim to measure the impact ofdifferent electrocautery settings directly with regards to adequacy of resection andsafety using a porcine study. Methods: After a standard 72 hour acclimation period, a12-week-old female domestic pig underwent induction of anesthesia followed by anupper endoscopy using an Olympus CV-180 Evis Exera II gastroscope. Four siteswithin both the esophagus and the stomach each underwent EMR using a CookDuette Multi-Band Mucosectomy device. Using an ERBE VIO 300 D generator, eachsite was resected using one of four preselected electrocautery settings: (A) ForcedCoag, 25 W, Effect 1; (B) EndoCut, Effect 2; (C) Operator Controlled Blend of ForcedCoag, 25 W, Effect 1 for 2 seconds then EndoCut, Effect 2 until completion; (D) SoftCoag, 80 W, Effect 4. The specimens were retrieved at time of EMR and sent topathology. Blinded to the setting used, they were measured from the muscularismucosa to the deepest margin of resection into the submucosa. In addition, eachresection site within the explant esophagus and stomach were marked to directlymeasure the depth of resection and thermal effects of cauterization. Results: Withinthe esophagus, EndoCut had the deepest level of resection into the submucosa(3799.3 mm) followed by Forced Coag (2770.5 mm) and then Operator ControlledBlend (1892.0mm). Soft Coag had the shallowest level of resection (405.6 mm).Conversely, EndoCut showed no level of submucosal resection within the gastricmucosa. Instead, Soft Coag had the deepest level of resection (778.3mm). ForcedCoag (369.6 mm) and Operator Controlled Blend (384.5mm) produced similar levelsof resection. After fixation with formalin, the markings on the explant organs wereno longer identifiable and these findings were excluded from this study.Conclusions: Our porcine study demonstrates that the choice of electrocautery set-tings alone can potentially make a measurable effect on the level of submucosalresection in both the esophagus and stomach. Also certain settings may havediffering effects when comparing esophageal or gastric mucosa, as seen with En-doCut. Limitations to our study include potential variances in adequate purchase ofthe mucosa within the Duette cap impacting depth of resection as well as theinability to measure thermal injury from electrocautery on the explant organs.Further studies will aim to overcome these by increasing the number of resectionsites and modifying the explant marking technique. Nonetheless, our study dem-onstrates that the choice of electrocautery settings may impact the depth of EMRand in turn influence both the adequacy of resection and potential for injury.

Pathology Review of Endoscopic Mucosal Resections with Different Elec-trocautery Settings

Specimens of Endoscopic Mucosal Resection with Different ElectrocauterySettings


ID: 3522470TRANSORAL INCISIONLESS FUNDOPLICATION (TIF)FACILITATES REMISSION OF INTESTINAL METAPLASIAAND DYSPLASIA IN PATIENTS UNDERGOINGENDOSCOPIC ERADICATION OF BARRETT’S ESOPHAGUSNicholas A. Hoerter*, Michael S. Smith, Rebekah E. Dixon, Zachary Spiera,Monica Saumoy, Prashant Kedia, David P. Lee, Amy Tyberg,Michael Makar, Nikhil A. Kumta, Satish Nagula, Christopher J. DiMaioBackground: The standard of care for dysplastic Barrett’s esophagus (BE) is endo-scopic eradication therapy (EET), with endoscopic mucosal resection (EMR) ofnodular lesions followed by field ablation. Up to 10-15% of patients are refractory totreatment, with persistent intestinal metaplasia or dysplasia, likely due to ongoingesophageal refluxate exposure. Transoral incisionless fundoplication (TIF) reducesthe burden of gastro-esophageal reflux disease (GERD) via endoscopic bolstering ofthe GE flap valve. Through improved reflux control, TIF should improve efficacy ofEET. Despite this potential, landmark TIF studies have excluded BE patients. Theaim of this study was to examine safety, feasibility and impact of TIF on both BEsurveillance and EET. Methods: Retrospective, multicenter study of adult patientswith histologically confirmed BE who have had either a traditional TIF or a hybridTIF (TIF with concurrent surgical hernia repair, cTIF). Primary outcomes includedfeasibility of BE surveillance or EET following TIF, rates of complete remission ofintestinal metaplasia (CR-IM) or dysplasia (CR-D) following TIF, and adverse events(AE) related to EET post-TIF. Results: A total of 11 patients met inclusion criteria(median age 59, 55% male, Table 1). The median pre-TIF Prague score was C2M3,


Abstracts


with nearly half of patients having some form of dysplastic BE. EET was performed inthree patients (27%) prior to TIF, with one patient achieving CR-IM. EET wasincomplete due to lack of healing post-EET in two patients. Most patients (64%)underwent cTIF, and all TIFs were technically successful with no AEs reported. Post-TIF follow up was for a median of 334 days (98-1574, Table 2), with 64% of patientsundergoing endoscopy. All cases of esophagitis resolved. One patient achieved CR-IM and another CR-D without EET. There was no new dysplastic BE found duringpost-TIF follow-up. EET was performed in three patients post-TIF, two with radio-frequency ablation (RFA) and another with RFA and EMR. Both patients with BEcontaining high grade dysplasia that underwent post-TIF EET achieved CR-IM. Ofnote, these patients could not complete EET pre-TIF due to severe or non-healingesophagitis after prior EET. One patient had subsequent histologic recurrence ofnon-dysplastic BE. Discussion: TIF is safe and feasible in BE patients and can facili-tate healing of erosive esophagitis and subsequent EET. Spontaneous resolution ofboth BE and dysplasia was seen post-TIF, without new cases of dysplasia. In patientswhere BE persisted EET was completed without AEs. Further investigations of TIFshould include BE patients, given the results of this study which demonstrate apotential new role for this anti-reflux technology in BE management.

Table 1. Pre-operative demographic, clinical, and endoscopic data.GERD Z gastroesophageal reflux disease; PPI Z proton pump inhibitor;H2RA Z histamine 2 receptor antagonist; POEM Z per oral endoscopicmyotomy; EET Z endoscopic eradication therapy; TIF Z transoral inci-sionless fundoplication; EMR Z endoscopic mucosal resection; RFAZ ra-diofrequency ablation; CR-IM Z complete remission of intestinalmetaplasia; CR-D Z complete remission of dysplasia

Table 2. Procedural details and post-operative outcomes. TIFZ transoralincisionless fundoplication, PPI Z proton pump inhibitor; H2RA Z hista-mine 2 receptor antagonist; GERD Z gastroesophageal reflux disease;BE Z Barrett’s Esophagus; EET Z endoscopic eradication therapy;EMR Z endoscopic mucosal resection; RFA Z radiofrequency ablation;CR-IM Z complete remission of intestinal metaplasia; CR-D Z completeremission of dysplasia*cTIF or Hybrid TIF is defined as a combined laparoscopic hiatal herniarepair and transoral incisionless fundoplication **Adverse symptomswere defined as bloating, dysphagia, flatulence


Abstracts



ID: 3526609STRETTA USE FOR GERD : A SYSTEMATIC REVIEW ANDMETA-ANALYSISAdnan Malik*, Mahum Nadeem, Umer Farooq, Abdullah Sohail,Khadija Naseem, Muhammad I. Malik, Sohira MalikBackground: Stretta procedure is a well-established, minimally invasive endoscopicprocedure for treating gastroesophageal reflux disease (GERD). We performed thissystematic review and meta-analysis to investigate the efficacy of this procedure inGERD management. Methods: We searched PubMed for English language clinicalstudies of the Stretta procedure. We used Cochrane’s tool for the assessment of therisk of bias across studies. We analyzed with risk ratio (RR) for dichotomous out-comes, using the Dersimonian–Laird method. Our meta-analysis’s statistical het-erogeneity was assessed using the I2 statistic, and we performed the analysis ofheterogeneous outcomes under the random-effects model. Outcome endpointsincluded daily proton pump inhibitor (PPI) use, heartburn score, esophageal acidexposure on media, lower esophageal sphincter (LES) pressure, HRQL score, De-meester score, and SF-36/SF-12 mental scores. Results: A total of 28 studies wereincluded. Comparing daily PPI use before and after stretta, data pooling resulted in asignificant association between baseline and follow up (RR Z 1.06: 95%. CI 0.951.81). A significantly higher chance of recovery was confirmed (RR Z 1.06: 95%. CI0.95 1.81). Regarding heartburn score on stretta and Heartburn score off stretta, astatistically significant pooled estimate of treatment effect was found (RR Z 1.66,95% CI 1.12- 2.47). As for esophageal acid exposure on Media 24-h pH before andafter stretta, the pooled effect estimate was statically significant (RR Z 1.10 95% CI1.88 – 1.37). LES pressure at baseline and follow-up revealed an overall effect of (RRZ 0.94, 95% CI: 0.88 – 1.37). Comparing HRQL baseline and follow-up levels, post-procedural values were statistically significant (PZ0.002). Demeester score and SF-36/SF-12 mental for pre and post stretta revealed significant improvements (RR Z1.59, 85% CI: 1.40 - 1.81) and (RR Z 1.00, 95% CI: 0.92 – 1.09). Conclusion: Ourresults provide more support to the Stretta procedure’s effectiveness in the treat-ment of GERD; interventions for a longer time were more effective in reducingheartburn score and the need for PPI usage.

GERD symptoms before and after Stretta

PPI Use before and After Stretta


ID: 3524500CHARACTERISTICS AND OUTCOMES OF EARLY VSDELAYED DOOR-TO-ENDOSCOPY TIME INESOPHAGEAL FOREIGN BODY IMPACTIONFredy Nehme*, Suman Sahil, Mohamed Ahmed,Laith Al momani, Ishaan Jakhar, Monica GaddisIntroduction: Esophageal foreign body impaction (EFBI) is a relatively commongastrointestinal emergency usually requiring an urgent endoscopic procedure torelieve the impaction. Current guidelines recommend removal of EFBI within 24hours of ingestion as delay decreases the success of successful removal and in-creases the risk of perforation. The rates of perforation and surgical interventionrange from 0.2% to 7.5%. Data evaluating characteristics and outcomes of door-to-endoscopy time in EFBI is lacking. Our study aims to compare patient outcomes ofEFBI between early (within 12 hours of hospital presentation) vs delayed (>12 hoursfrom hospital presentation) endoscopic intervention. Methods: We used the CernerHealth Facts� nationwide EMR database retrospective cohort to identify all hospitalpresentations for adult patients (� 18 years) presenting with EFBI between 01/01/2010 and 11/30/2018. Patients were classified as having foreign body in the esoph-agus by querying the primary admission diagnosis field for the ICD-9-CM code 935.1.Patients requiring an upper endoscopy were selected and categorized as early ifendoscopy was performed within 12 hours and delayed between 12 and 48 hours.Descriptive statistics were reported as median (IQR) for continuous variables, andfrequency (%) for categorical variables. For continuous variables, Mann-Whitney Utest was used to compare medians. For categorical variables, the Chi-square test wasused to assess the association. Results: Out of 7,324 patients included in our analysis,6,482 had an upper endoscopy performed within 12 hours of presentation and 842between 12 and 48 hours. Patients undergoing delayed endoscopy were older(median age of 65 vs. 56 years, p<0.001), and more likely to be males. Patients in thedelayed group had a significantly longer length of stay (median of 1.72 vs. 0.24 days,p<0.001), higher perforation rate (1.3% vs 0.6%, pZ0.002), and higher mortality rate(2.1% vs 0.25%, p<0.001) compared to the early endoscopy group. Conclusion:While guidelines recommend upper endoscopy within 24 hours of foreign bodyingestion, dependence on patient history to determine timing of ingestion might notalways be accurate, particularly in those with cognitive impairment. Performance ofan upper endoscopy beyond 12 hours of hospital presentation was associated withprolonged length of stay, higher perforation and mortality rates. In the delayedgroup, the significantly elevated mortality rate surpassing the perforation rate sug-gests that the noted difference could reflect worse underlying clinical status onpresentation that earlier endoscopy was not deemed safe. It may be advisablehowever to perform upper endoscopy within 12 hours of presentation if clinicalstatus and endoscopic availability permits.


Abstracts


Characteristics and outcomes of early vs delayed door-to-endoscopy inesophageal foreign body impaction


ID: 3520684COMPLETE ERADICATION OF INTESTINAL METAPLASIAIN PATIENTS WITH BARRET’S ESOPHAGUS WITHADVANCED NEOPLASIA PREVENTS RECURRENTDYSPLASIARyosuke Kobayashi*, Natalia C. Calo, Jeffrey D. Mosko, Gary R. May,Christopher TeshimaBackground: Barrett’s esophagus (BE) is a well-established precursor of esophagealadenocarcinoma. Endoscopic mucosal resection (EMR) and radiofrequency ablation(RFA) are considered safe and effective treatments for the eradication of BE. How-ever, little is known about the impact of achieving complete eradication of IM(CRIM) following the complete eradication of dysplasia (CRD), and whether or notCRIM reduces the risk of recurrent dysplasia. Aims: The primary aim was to comparethe incidence of recurrent dysplasia between patients who achieved and did notachieve CRIM after successful CRD following endoscopic treatment for BE-associ-ated high-grade dysplasia (HGD)/intramucosal cancer (IMC). Methods: Retrospec-tive cohort study from a prospectively collected database of consecutive adultpatients with BE associated HGD and/or IMC that underwent EMR or RFA between2001 and 2019 in a tertiary care center in Canada. Patients were excluded if they hadunfavorable histology on EMR (submucosal or lymphovascular invasion), and sub-sequently underwent surgery or chemoradiotherapy, or if they declined furthertreatment. A Cox proportional hazards regression model was used to assess theassociation between CRIM and recurrent dysplasia and to adjust for potential con-founders. Time to recurrence was calculated from the date of CRD to the timerecurrence was confirmed. Results: A total of 433 patients treated with EMR or RFAwere identified. Of these, 381 (88%) achieved CRD and 345 (80%) patients achievedCRD and had adequate follow-up and were included in the analysis. A total of 266(77%) achieved CRIM. Baseline characteristics of the cohort are presented in Table1.The mean age was 64 years (SD 10.7); 82% were male; median period of follow-upsince initial treatment for BE with HGD/IMC was 45.9 months (IQR 25.9, 93.1). 20patients (5.8%) had recurrent dysplasia over a median post-CRD follow up period of30.8 months (IQR 14.9, 54.5). Kaplan Meier survival curves revealed that time free ofrecurrence in those that achieved CRIM was significantly higher (p Z 0.002). In themultivariable analysis, CRIM was associated with a significant 80% lower hazard ofrecurrence (HR 0.2, 95%CI 0.1,0.6), whereas the number of endoscopic treatmentsto achieve CRD was associated with a significant 10% higher hazard of recurrence(HR 1.1, 95%CI 1.0, 1.2). Conclusion: Achieving CRIM following CRD reduces therisk of recurrent dysplasia and should be considered an important treatment targetamong patients undergoing endoscopic therapies for Barrett’s esophagus with HGDor IMC.


ID: 3524230AFTER-HOURS PRESENTATION IS ASSOCIATED WITHHOSPITAL ADMISSION AND LONGER TIME TOPROCEDURE IN ESOPHAGEAL FOREIGN BODYIMPACTIONFredy Nehme*, Suman Sahil, Monica Gaddis, Mohamed Ahmed,Ishaan Jakhar, Laith Al momani, Wendell K. ClarkstonIntroduction: Esophageal foreign body impaction (EFBI) is a common gastroenter-ological emergency with an annual incidence of 11 per 100,000 person years. Asurgent endoscopic evaluation is usually required to relieve the impaction, patientswith EFBI frequently present after-hours. Data describing the characteristics andoutcomes of patients presenting after-hours for EFBI is scarce. We aimed to assessthe difference in demographics, complication rate, length of stay, and time totherapeutic procedure between patients presenting during regular working hoursand those presenting after-hours requiring an upper endoscopy for EFBI. Methods:We used the Cerner Health Facts� nationwide EMR database retrospective cohort toidentify all hospital presentations for adult patients (� 18 years) presenting withEFBI between 01/01/2010 and 11/30/2018. Patients were classified as having foreignbody in the esophagus by querying the primary admission diagnosis field for theICD-9-CM code 935.1. Patients requiring an upper endoscopy were selected and


Abstracts


categorized as day-time presentation if they presented to the ED between 8 AM and8 PM and after-hours presentation between 8 PM and 8 AM. Descriptive statisticswere reported as median (IQR) for continuous variables, and frequency (%) forcategorical variables. For continuous variables, Mann-Whitney U test was used tocompare medians. For categorical variables, the Chi-square test was used to assessthe association. Results: Out of 7,324 patients included in our analysis, 5065 pre-sented during day-time hours, and 2,259 after-hours. There was no difference ingender, race, and distribution in urban or rural hospitals between the 2 groups.Patients presenting after-hours were younger, and presented more often to teachinghospitals. Patients presenting between 8 PM and 8 AM had a significantly longerlength of stay (median of 10.32 vs. 5.76 hours, p<0.001), door-to-endoscopy time(median of 3.84 vs 2.88 hours, p<0.001), and were more likely to get admitted.There was no significant difference in perforation (0.7% vs 0.8%, pZ0.456) andmortality (0.5% vs 0.4%, pZ0.355) rates between the 2 groups. Conclusion: After-hours ED arrival is associated with a longer time-to-procedure, prolonged length ofstay, and higher likelihood of hospital admission. Patient mortality and increasedcomplications were not seen despite delays in management of after-hours EFBI.However, patient comfort and increased costs of care due to prolonged ER stays andincreased admissions should prompt more timely endoscopic intervention for EFBIif endoscopic availability permits.

Characteristics and outcomes of day-time vs after-hours presentation inesophageal foreign body impaction


ID: 3526780PROBE BASED CONFOCAL ENDOMICROSCOPY MAYINCREASE DETECTION OF LOW GRADE DYSPLASIA INMALE VETERANS PREVIOUSLY DIAGNOSED WITH NONDYSPLASTIC SHORT SEGMENT BARRETT’S ESOPHAGUSUNDERGOING SURVEILLANCEKaren Chang, Nicole Shah-Ghassemzadeh, Kenneth J. Vega,Christian S. Jackson*Introduction: Probe based confocal endomicroscopy (pCLE) has allowed forincreased detection of dysplastic mucosa with Barrett’s esophagus (BE). Fewstudies have focused on the use of pCLE in the diagnosis of dysplasia in shortsegment Barrett’s esophagus (SSBE). Not only is there evidence to show that stan-dard biopsy techniques may miss dysplasia in all forms of BE, but SSBE may bemissed altogether. The primary aim of our study was to determine if pCLE could beeffective in diagnosing dysplastic mucosa in patients undergoing surveillanceendoscopy in SSBE. Methods: Patients diagnosed with SSBE between January 1,

2018 and January 1, 2020 at the VA Loma Linda Healthcare System (VALLHCS) wereincluded. Esophagogastroduodenoscopy (EGD) was performed using a high defin-tion diagnostic upper endoscope (Olympus,Center Valley PA). All patients wereundergoing BE surveillance. Patients who underwent pCLE were compared to thoseundergoing BE surveillance with standard biopsy protocol. All patients in the stan-dard biopsy protocol group underwent high-defintion white light examination (HD-WLE). All pCLE examinations were performed by one gastroenterologist (C.S.J.).HD-WLE was initially performed followed by narrow band imaging and pCLE usingGastroFlex UHD Confocal Miniprobe (Cellvizio, Mauna Kea Technologies). Age, sex,number of EGDs prior to a diagnosis of dysplasia, hiatal hernia length and pCLEfindings were assessed. SSBE was defined using Prague criteria as follows: Barrett’scircumference (C ) � 2cm and maximal length of Barret’t’s segment (M) � 3cm. Twopathologists reviewed all biopsies with a diagnosis of dysplasia. Continuous variableswere compared using a Fisher’s exact test with p�0.05 as statistically significant. Thisstudy was approved by the institutional review board for VALLHCS. Results: Twenty-nine patients were identified as having SSBE. The mean age of the of patients un-dergoing pCLE was 70 years of age as well as the mean age of patients who un-derwent standard biopsy. All patients included were male. Mean Prague Criteria forpCLE was C1, M2.25 and the mean for standard biopsy was C.4, M1.8. The meanhiatal hernia length for pCLE patients was 3.6cm while mean hiatal hernia length forstandard patients was 3.5cm. The mean number of EGDs performed prior to diag-nosis of LGD in pCLE group was 3 versus 2.25 in the standard biopsy protocol group.Low-grade dysplasia was detected in 86% (6/7) of the patients who underwent pCLEversus 31% (4/22) patients with standard biopsy protocol, pZ0.026. Conclusion: In aprimarily male veteran population, pCLE may be helpful in identifying low gradedysplasia in patients with SSBE that standard biopsy techniques may miss during BEsurveillance.


ID: 3521206SEATTLE PROTOCOL IS MORE EFFECTIVE INDETECTION OF DYSPLASIA COMPARED TOTECHNOLOGY-ASSISTED TARGETED BIOPSIES INPATIENTS WITH BARRETT’S ESOPHAGUSNoam Peleg*, Steven Shamah, Iris Dotan, Boris SapoznikovBackground and aims: With the development of virtual chromoendoscopy andnarrow band imaging (NBI) in endoscopic evaluation of patients with Barrett’sesophagus (BE), the role of random four quadrant biopsies (RFQB) according toSeattle protocol in the detection of dysplasia has been questioned. In this study weaim to evaluate the utility of targeted biopsies using high definition white light (HD-WL) endoscopy and NBI compared to RFQB in first detection of dysplasia in patientswith BE. Methods: A prospective cohort of patients with proven BE in a tertiaryreferral center was retrospectively analyzed. All biopsies that were taken duringfollow up were reviewed by an expert GI pathologist. Both HD-WL endoscopy andNBI were tandemly used with RFQB in each endoscopic procedure and only patientsthat were diagnosed with dysplasia or developed dysplasia during follow up werepart of the statistical analysis. Results: A total of 155 out of 331 patients (46.8%) withBE were diagnosed with dysplasia during median follow up of 4 years (IQR 2.4-5.1years) and were part of the statistical analysis (Figure 1). Mean age was 63.6 (�9.5)and 79.9% of the patients were males. Eighty-two patients had a diagnosis ofdysplasia at presentation whereas 84 patients developed dysplasia during follow up.Sixty-seven out of 82 patients with dysplasia at presentation (81.7%) and 65 out of 84patients that were diagnosed with dysplasia during follow up (77.4%) were diag-nosed using RFQB (Figure 2). In addition, whereas all the events of esophagealadenocarcinoma were diagnosed using targeted biopsies, 57.1% of the events ofhigh-grade dysplasia and 86.9% of the low-grade dysplasia were diagnosed usingRFQB. Out of the targeted biopsies, 35.5% were targeted after HD-WL evaluationand 64.5% were targeted after evaluation with NBI. Conclusion: Our findingsdemonstrate the significance of Seattle protocol in the detection of both low andhigh grade dysplasia in patients with BE. The standard RFQB should remain themainstay of endoscopic surveillance in this population.


Abstracts


Figure 1. Study flow chart

Figure 2. Diagnosis of dysplasia according to detection modatily in prev-alent and incident events


ID: 3520683CLINICOPATHOLOGICAL FACTORS ASSOCIATED WITHMAJOR RECURRENCE AFTER SALVAGE ENDOSCOPICRESECTION FOR PATIENTS WITH LOCAL FAILUREAFTER DEFINITIVE CHOMORADIOTHERAPY FOR STAGEI ESOPHAGEAL SQUAMOUS CELL CARCINOMAMai Ego*, Tomohiro Kadota, Hiroki Yamashita, Keiichiro Nakajo,Yusuke Yoda, Satoru Nonaka, Haruhisa Suzuki, Shigetaka Yoshinaga,Ichiro Oda, Seiichiro Abe, Tomonori YanoIntroduction: Local failure remains one of the major problems of definitive chemo-radiotherapy (CRT) for esophageal squamous cell carcinoma (ESCC). Salvageendoscopic resection (sER) has been performed for superficial local failure, and itstechnical feasibility and favorable local control were reported, especially in clinical(c) Stage I ESCC. However, major recurrence, which requires more invasive treat-ment than repeated sER, is a clinical issue after sER, and little is known about thefactors associated with major recurrence. Methods: This retrospective study aimedto clarify the factors associated with major recurrence after sER in patients with

cStage I ESCC. This study included patients who met the following criteria: (1) pa-tients with cStage I ESCC who were treated with CRT, (2) those who underwent sERas initial treatment for local failure between 1999 and 2018 at our institutions (3)those with a follow up longer than one year. Local failure included residual lesionsthat persisted at the primary site without achieving complete response after CRT,and local recurrence lesions that developed at the primary site after achievingcomplete response after CRT. The indications of sER were as follows: 1) biopsy-proven local failure; 2) depth invasion confined to SM1 endoscopically; and 3)absence of lymph node or distant metastasis on CT scan. Those who underwentadditional salvage photodynamic therapy or surgery immediately after sER wereexcluded. We evaluated the cumulative major recurrence rate (CmRR) after sER andassessed the factors associated with CmRR. CmRR was defined as the cumulative rateof the patients with event of major recurrence including major local, lymph node, ordistant recurrence, or death from primary ESCC, and those without event censoredat either the date of last visit or death from other cause. Major local recurrence wasdefined as those required more invasive treatment than repeated sER. This studywas approved by an institutional review board in our institutions. Results: Finally,total 58 patients (14 with residual lesions and 44 with local recurrences) wereeligible. The numbers of pEP/LPM/MM/SM1/SM2 in the sER specimens were 19/12/10/5/12. The positive lateral and vertical margin were 21 and 9, respectively, andlymphatic and vascular invasion were positive in 7 and 5 lesions, respectively withoverlapping. During the median follow-up of 53 months (range 4-208), majorrecurrence occurred in 18 patients including 7 major local recurrences and 11 lymphnode and/or distant metastasis. The 3-/5-year CmRR after sER were 22% and 32%,respectively. Residual lesion (vs. local recurrence, Hazard ratio 2.917, PZ 0.030) wassignificantly associated with CmRR in univariate analysis. Conclusion: Patients withresidual lesions after CRT for cStage I ESCC should be carefully followed up formajor recurrence after receiving sER.


ID: 3526343FUNDOPLICATION IS RARELY REQUIRED FORCOMPLETE ERADICATION OF INTESTINAL METAPLASIAIN PATIENTS UNDERGOING RADIOFREQUENCYABLATION FOR DYSPLASTIC BARRETT’S ESOPHAGUSZeyun Xue*, Cary C. Cotton, Swathi Eluri, Evan S. Dellon,Nicholas J. ShaheenBackground: Radiofrequency ablation (RFA) is a safe and effective endoscopic ther-apy for dysplastic Barrett’s esophagus (BE), a precursor to esophageal adenocarci-noma. Failure to achieve complete eradication of intestinal metaplasia (CEIM) couldbe caused by uncontrolled acid reflux despite maximal medical therapy, which maybe mitigated by fundoplication. The degree to which fundoplication is required forpatients to achieve CEIM is unclear, with reports as high as 20% in those undergoingablative therapy. Aim: To describe the use of rescue fundoplication and its effectsamong patients that struggle to achieve CEIM in a single-center cohort of patientsundergoing RFA. Methods: This is a retrospective study of participants undergoingRFA for Barrett’s esophagus at a tertiary care center. Participants were included fromthe time of their first treatment session and followed longitudinally. Participants withinvasive esophageal adenocarcinoma (EAC) and esophagectomy were excluded.Rescue fundoplication was defined as the use of fundoplication after initiation ofendoscopic eradication therapy (EET) due to erosive esophagitis despite optimaltwice daily proton pump inhibitor therapy or failure to completely eradicate BEdespite repeated treatments. We calculated the rate of rescue fundoplication in allparticipants and plotted product-limit estimates of the rate of CEIM among partici-pants who underwent fundoplication before treatment, rescue fundoplication dur-ing treatment, or no fundoplication. For the rate of CEIM, we included onlyparticipants with one or more years follow-up to exclude patients still receivingactive treatments. Results: Among 463 included participants, 362 (78.2%) had at leastone year of follow-up (Table). Mean age was 66�11 years and 69% were men. Meanbaseline segment length was 4.9�3.4 cm and nearly 50% of the participants had highgrade dysplasia (HGD) baseline. At baseline, 33 (7.1%) of participants had a historyof fundoplication. An additional 6 (1.3%) underwent rescue fundoplications duringtreatment, an incidence rate of 3.6 per 1,000 person-year. Those participants thatrequired rescue fundoplication during treatment all achieved CEIM but had a longertime to CEIM compared to those with no or baseline fundoplication (Figure).Conclusion: Sparing use of fundoplication, at rates less than half than previously re-ported, still results in attaining CEIM at rates �85%. An adaptive strategy using se-lective rescue fundoplication in BE patients resistant to EET can yield a high rate ofCEIM with a need for fundoplication in less than 2% of cases.


Abstracts


Figure. Kaplan-Meier Estimate of the Proportion of Participants with atleast One Year of Follow-up Without Complete Eradication of IntestinalMetaplasia by Years After First Radiofrequency Ablation Treatment.


ID: 3520803SELF-EXPANDABLE METAL STENTING FORESOPHAGEAL FISTULA CLOSURE: INCREASING THEODDS OF SUCCESS.Rui S. Magalhães*, Tiago L. Capela, Tiago Cúrdia Gonçalves,Pedro Boal Carvalho, Bruno Rosa, José CotterIntroduction: Esophageal self-expanding metal stent (SEMS) can be considered fortreatment of anastomotic leaks and fistulas. We aim to assess predictors for SEMSsuccess in the closure of fistulas and anastomotic leaks. Methods: Retrospectivecohort study, including consecutive patients submitted to esophageal stenting forfistula or anastomotic leaks closure, from 2012 to 2020. The outcome variable wasfistula closure evaluated 8 weeks after stent placement. Univariate analysis tested thestatistical significance towards the outcome. Logistic regression models quantifiedthe correlation. Results: We included 30 patients, 18 (60%) were men, and the meanage was 60 years old. We report 26 (87%) anastomotic leaks, mainly in the post-operatory of total (nZ21) and partial gastrectomies (nZ5). Eleven gastrectomieswere bariatric and 15 for gastric neoplasia. Only 4 fistulas appeared (13.3%) in thescenario of esophageal neoplasia. Twenty-three (76.7%) patients achieved fistula/anastomotic leak resolution. From the other 7 patients (24.6%), 5 died after the 8-week period and 2 lost follow-up. Twenty (66%) SEMS were partially covered, and 10(33%) fully covered. The “stent-in-stent” technique was performed in 10 (33%) casesfor stent removal. Minor complications occurred in 14 (46%) cases and majorcomplications in 1 patient (3.3%), a case of esophageal perforation. The variablessmoking (odds ratio 0.059; CI 95% [0.006-0.594]; p value 0.016), a neoplastic causeof fistula/anastomotic leak (odds ratio 0.061; CI 95% [0.005-0.739]; p value 0.028)and oral systemic corticotherapy (odds ratio 0,034; CI 95% [0.003-0.416]; p value0.008) were statistically associated with lower fistula/anastomotic leaks closure.Conclusion: Temporary esophageal SEMS placement is a safe and effective endo-scopic procedure to ensure esophageal fistula/anastomotic leaks closure. Smoking,corticosteroid use and malignancy significantly decrease the odds of fistula/anasto-motic leak closure. Optimizing the selection of patients for SEMS placement mightincrease the chances of procedure’s success.


Abstracts



ID: 3517856AN EXTRA 1-CM SAFETY MARGIN DURINGENDOSCOPIC SUBMUCOSAL DISSECTION CANCONTROL SUBSQUAMOUS TUMOR EXTENSION OFADENOCARCINOMA IN THE ESOPHAGOGASTRICJUNCTION: A PROSPECTIVE FEASIBILITY STUDYTaku Manabe*, Yasuaki Nagami, Kei Yamamoto, Shinji Hirano,Mitsuhiro Kono, Tadashi Ochiai, Yuki Kakiya, Masafumi Yamamura,Kojiro Tanoue, Taishi Sakai, Hirotsugu Maruyama, Masaki Ominami,Yuji Nadatani, Shusei Fukunaga, Koji Otani, Shuhei Hosomi,Fumio Tanaka, Koichi Taira, Toshio Watanabe, Yasuhiro FujiwaraBackground and Aims: The incidence of esophagogastric junction (EGJ) adenocarci-noma has recently increased. Furthermore, EGJ cancers can have subsquamoustumor extension that complicates an accurate determination of the proximal tumormargin and creates clinically problematic positive lateral margins after endoscopicsubmucosal dissection (ESD). Our previous retrospective study revealed that usingan extra 1-cm safety margin during ESD for EGJ cancers was associated with negativelateral margins in all cases, regardless of subsquamous tumor extension. This pro-spective study evaluated whether adding an extra 1-cm safety margin during ESD forEGJ cancers could help achieve negative lateral margins. Methods: This single-centerprospective feasibility study included patients with suspected EGJ cancer. The in-clusion criteria were: (1) an EGJ tumor diagnosed as Siewert’s type II classificationbased on endoscopic examination, (2) a pathological diagnosis of definite or sus-pected adenocarcinoma, (3) an endoscopic classification of cT1a-M, (4) no signs oflymph node or distant metastasis during computed tomography. In all cases,endoscopic signs of subsquamous tumor extension were evaluated using followingfour modalities (conventional white light endoscopy, non-magnifying endoscopywith narrow-band imaging (NBI), magnifying endoscopy with NBI, and magnifyingendoscopy with acetic acid application), and marking dots were placed on the oralside at 1 cm from the endoscopic sign or 1 cm from the squamous-columnarjunction. The primary outcome was the rate of complete resection and the sec-ondary outcomes were treatments outcomes and subsquamous tumor extensionincidence, length, and preoperative diagnosis rate. For the present study, the lengthof subsquamous tumor extension was defined as the length based on the freshspecimen photograph. Result: The study enrolled 14 patients and 2 patients wereexcluded. Twelve patients were assessed, included in 9 men and 3 women. Themedian age was 64.0 years (range: 50-80 years). The histological diagnoses wereBarrett’s adenocarcinoma in 5 cases and EGJ adenocarcinoma in 7 cases. Thecomplete resection rate was 91.7% (11/12). All lesions were laterally containedwithin the 1-cm margin, which resulted in negative lateral margins. The incidence ofsubsquamous tumor extension was 75% (9/12), the median extension length was 5.7mm (range: 1–24.8 mm), and the endoscopic diagnosis rate was 66.7% (8/12). Thecurative resection rate was 66.7% (8/12) and two patients had stricture. Conclusions:Adding an extra 1-cm safety margin during ESD for EGJ cancers appears to be safeand may help achieve negative lateral margins. Given the difficulty of diagnosingsubsquamous tumor extension, we recommend adding the 1-cm safety marginduring ESD for EGJ cancers.

SATURDAY, MAY 22, 2021Esophagus 1Poster

ID: 3518264INCREMENTAL YIELD OF HIGH DEFINITION WHITELIGHT, NARROW BAND IMAGING, AND ACETIC ACID ATIDENTIFYING DYSPLASIA IN BARRETT’S ESOPHAGUSMatthew Fasullo*, Milan Patel, Noah Hillerbrand, Morgan Denecke,George Smallfield, Robert Lippman, Pritesh R. Mutha, Tilak ShahIntroduction: To optimize yield for identifying dysplasia in Barrett’s Esophagus (BE),guidelines recommend careful high definition white light endoscopy (HD-WLE)examination, as well as 4-quadrant biopsies at 1-2 cm intervals, i.e. – Seattle protocolbiopsies (SPB). In some studies, narrow band imaging (NBI) and acetic acid (AA)

chromoendoscopy achieved accuracy comparable to SPB. The aims of our studywere to assess whether (a) combining all 4 modalities (HD-WLE, NBI, AA, and SPB)could increase diagnostic yield compared to HD-WLE + SPB, and (b) to assess theincremental yield of NBI and AA at identifying dysplasia. Methods: We conducted aretrospective, propensity score matched case control study using prospectivelymaintained databases at 2 tertiary medical centers. The experimental arm includedpatients who sequentially underwent HD-WLE, NBI, AA chromoendoscopy, and SPBby BE experts. Controls were patients who underwent HD-WLE and SPB by anyphysician. Patients referred from outside facilities for previous diagnosis of dysplasiawere excluded. In both groups, dysplasia was confirmed by a second expertpathologist. Controls were 1:1 propensity score matched for age, gender, tobaccohistory, presence of hiatal hernia, and long segment BE (i.e. - �3 cm). Results: 152patients were included in the study (71 in experimental arm, 71 controls). As ex-pected, due to propensity matching, baseline demographics were similar betweenthe 2 groups (Figure 1a). The addition of NBI and AA chromoendoscopy increasedyield for low-grade dysplasia (LGD) when compared to HD-WLE and Seattle protocolbiopsies alone (18% vs. 4%, p 0.006). Diagnostic yield for high-grade dysplasia(HGD), adenocarcinoma and overall yield for dysplasia or cancer did not differsignificantly between the two groups (Figure 1b). Within the experimental group,the incremental yield of NBI over HD-WLE for dysplasia and cancer was 1.2%; in-cremental yield of AA chromoendoscopy over HD-WLE + NBI was 2.3% (Figure 2a).The bulk of the higher LGD yield in the experimental group compared to controlswas explained by increased identification on HD-WLE by physicians who utilized NBIand AA (Figure 2b). On average, NBI increased procedure duration by 1.5 minutes,and AA increased procedure duration by 1.85 minutes. Discussion: Our resultsindicate that training efforts directed towards improving HD-WLE inspection arelikely to have a higher impact at identifying dysplasia when compared to additionaltraining in NBI and AA chromoendoscopy. Given their low cost and relatively effi-ciency to perform, NBI and AA are valuable adjuncts to further increase LGD iden-tification in expert centers.

Figure 1. Demographics and Primary Outcomes


Abstracts


Figure 2. Incremental Yield for Dysplasia Detection


ID: 3527213THIRD SPACE ENDOSCOPY AFTER FORMALENDOSCOPY ADVANCED FELLOWSHIP TRAINING INTHE US: ONE YEAR LINEAR FOLLOW UP OFINDEPENDENT PRACTICEMohamed Abdelfatah Magdy*, Ali M. Ahmed, Shajan Peter,Douglas R. Morgan, Qiang CaiIntroduction: Third space endoscopy includes peroral endoscopic myotomy (POEM)and gastric peroral endoscopic pyloromyotomy (GPOEM). Very few advancedendoscopy fellowships offer comprehensive training in third space endoscopy inaddition to ERCP and EUS, given the risk associated with these procedures. Multiplestudies have reported the learning curve for POEM. We followed a single traineeexperience following formal third space endoscopy training. Method: We analyzedthe number of cases of third space endoscopy cases performed in one-year trainingand calculated the learning curve. Then we followed up the data of the procedurethat was performed by the same formal trainee after practicing independently in atertiary referral center. Video recording of all procedure was available for review byexpert attendings. Results: Following 15 months of independent practice, 115 thirdspace procedures were performed (53 POEM, 62 GPOEM). 40 out of the 53 patientswho underwent POEM had previous treatment, including Botox injection, pneu-matic dilation, or heller myotomy. Twelve patients out of the 62 patient who un-derwent GPOEM relied entirely on tube feeding or TPN The average procedure timefor POEM and GPOEM was 47 � 14 minutes. Technical and clinical success wasachieved in all POEM procedure. One patient needed further dilation after sixmonths follow up. GPOEM technical success and short term clinical success were

achieved in all patients. The post-procedure hospital stay was one day in all exceptseven patients. Conclusion: Our one linear follow-up results suggest that formaltraining in third space endoscopy yields excellent outcomes in the transition to ac-ademic practice. This experience may be helpful in the design of training and cer-tification programs.


ID: 3519045COMPARISON OF RADIOFREQUENCY ABLATION TOSPRAY LIQUID NITROGEN CRYOTHERAPY IN THEMANAGEMENT OF DYSPLASIA IN BARRETT’SESOPHAGUS: A SINGLE CENTER EXPERIENCEMatthew Fasullo*, Milan Patel, Spencer Harris, Ramzi Hassouneh,Tilak Shah, George SmallfieldIntroduction: Barrett’s esophagus (BE) is a well-recognized risk factor for esophagealadenocarcinoma (EAC). Endoscopic eradication prevents development of EAC.Presently, radiofrequency ablation (RFA) is the most common eradication therapy.While recent studies have suggested that balloon cryotherapy is non-inferior to RFAin the management of dysplastic BE, limited data exists regarding longitudinal out-comes of spray liquid nitrogen cryotherapy (SLNC) compared to RFA. This studyaims to bridge a knowledge gap assessing the number of sessions needed to suc-cessfully eradicate dysplastic BE and outcomes for those who failed initial treatmentmodality. Methods: This is a retrospective study conducted at VCU Medical Center(Richmond, VA) from 2010-2019. The first experimental arm included patients withdysplastic BE who underwent HD-WLE followed by RFA (Medtronic, Minneapolis,MN). The second experimental arm included patients with dysplastic BE who un-derwent HD-WLE followed by SLNC (Steris, Mentor, OH). Patients referred fromoutside facilities for previous diagnosis of dysplasia were excluded. If an area ofnodularity was identified on HD-WLE, then endoscopic mucosal resection wasperformed. In both groups, dysplasia was confirmed by a second expert pathologistprior to ablative therapy. Failure of treatment modality was defined as failure toachieve complete eradication of dysplasia (CE-IM) in 5 sessions or intolerance oftreatment due to side effects. The primary outcome was complete eradication ofintestinal metaplasia (CE-IM). Secondary outcomes were the number of sessionsrequired to achieve CE-IM along with outcomes after failing initial treatment mo-dality. Results: Baseline demographics were generally similar between both groups.Those in the SLNC cohort had a higher Charlson CI compared to those in the RFAcohort (Figure 1). The rates CE-IM were similar between the RFA cohort comparedto the SLNC cohort, 42 (76.3%) vs. 20 (68.9%), pZ0.467. Those in the RFA cohortachieved CE-IM in fewer treatment sessions compared to the SLNC cohort, 2.4 vs.3.9, pZ0.01 (Figure 2a). In those who failed initial treatment modality, switchingtherapy achieved similar rates of CE-IM between the two cohorts. Again, in thosewho switched therapy, the mean number of sessions to achieve CE-IM was lower inthe RFA cohort compared to the SLNC cohort, 2.75 vs. 4.71, pZ0.034 (Figure 2b).Discussion: In conclusion, both RFA and SLNC are similar in their rates of achievingCE-IM in our cohort although the mean number of sessions required to achieve CE-IM was higher in those who underwent SLNC. Although observational, our datasuggests that while both treatments are successful in achieving CE-IM, RFA may bemore cost-effective compared to SLNC given fewer treatment sessions are required.


Abstracts



ID: 3526678SEASONAL AND TEMPORAL VARIATIONS INESOPHAGEAL FOOD IMPACTIONS: A LONG-TERMTERTIARY CARE ANALYSISMuhammad Z. Hanafi*, Mohammad F. Madhoun, William M. TierneyBackground: Based on the impact of allergen driven conditions such as eosinophilicesophagitis (EoE) and seasonal variations in dietary habits, the possibility of a sea-sonal variation in esophageal food impaction (EFI) has been postulated. Somestudies have demonstrated a higher prevalence of EoE diagnoses during theallergen-heavy periods (Summer and Spring) whereas others have demonstrated novariation. We performed a long-term retrospective analysis to help clarify seasonaland temporal changes in EFI. Methods: EFIs in patients over the age of 18 presentingto our tertiary academic center from January 2005 to July 2019. All cases wereidentified by searching our endoscopy database for emergency room and inpatientspresenting with dysphagia. Electronic records were used to abstract all clinical anddemographic parameters. Cases were grouped according to the season of presen-tation into Summer (Jun/Jul/Aug), Spring (Mar/Apr/May), Fall (Sep/Oct/Nov), andWinter (Dec/Jan/Feb) along with a review of the underlying etiology and method ofremoval. Cases were further subdivided over two time periods, Group 1, Jan 2005 toDec 2011, and Group 2, Jan 2012 to Jul 2019 to examine temporal changes in thepresentation and management. Results: After excluding patients with preproceduraldiagnoses of esophageal cancers, achalasia, and altered surgical anatomy, 111 pa-tients with esophageal food impactions were included in the final analysis. Regardingseasonal variations in impaction events, cases were distributed throughout all 4seasons with 22.5% in Spring, 26.2% in Summer, 30.6% in Fall, and 20.2% in Winterwith no significant difference (pZ0.47) (Table 1). Following bolus removal, pepticstricture (43.2%) was the predominant endoscopic finding followed by ringedesophagus suggestive of EoE (20.7%) and normal esophagus (16.2%). To evaluatewhether there has been a temporal change the cohort was divided into two timeperiods, Group 1 (01/2005-12/2011) and Group 2 (01/2012-07/2019) and we identi-fied a significant shift towards a higher percentage of patients having findings sug-gestive of EoE (ringed esophagus or normal) 23.6% to 50% PZ0.004 (Table 2). Overthe entire cohort, removal of food bolus was accomplished primarily via net retrievalcatheter (37.8%) or push technique (33.3%) and there was no significant change inthe frequency of these techniques between Group 1 and Group 2. Conclusions:There does not appear to be a seasonal variation in EFI. However, there has been atemporal shift towards endoscopic findings suggestive of EoE. Whether the increasein EoE findings is due to an escalation of the incidence of EoE or endoscopists’increased awareness of the condition requires further study.


ID: 3522431COMPLETE CIRCUMFERENTIAL ESD FOR BARRETT’SNEOPLASIADouglas Motomura*, Robert BecharaBackground: Endoscopic submucosal dissection (ESD) is carving out an increasingrole in the treatment of esophageal neoplasia in the western world. Contrary toAsia, the majority of esophageal cancers in North America are associated with Bar-rett’s esophagus. Patients with circumferential advanced neoplasia were previouslymanaged by esophagectomy. Increased experience with ESD has allowed for anendoscopic alternative. We aim to present our experience with complete circum-ferential esophageal ESD at a North American referral centre. Methods: All patientsundergoing 100% circumferential esophageal ESD between Oct 2016 and June 2020at a single tertiary care centre in Canada were included in the cohort. Demographic,procedural data and lesion characteristics are presented in this series. Results: Eightpatients underwent 100% circumferential esophageal ESD during this period. Theindication for all cases was Barrett’s neoplasia. All patients had technically successfulprocedures with en bloc resection. Seven patients (88%) had R0 resections, definedas clear lateral and deep margins on histologic examination. One patient had posi-tive deep margins on histologic examination and proceeded to esophagectomy.Four patients (50%) had adenocarcinoma on final pathology, of which 3 (75%) hadupstaging from their initial biopsy.


Abstracts


The mean area of resected specimen was 57cm2 (SD 38.5) and the mean proceduretime was 217 minutes (SD 60). Procedural efficiency was 4.5 min/cm2 (SD 2.6). Sixpatients (86%) developed strictures in the follow-up period. All strictures wereendoscopically managed. There were no significant adverse events. Conclusion: Ourexperience with circumferential ESD shows high technical success despite extensiveresections. Development of esophageal stricture is common, and endoscopicallymanageable. Circumferential ESD must be weighed against the morbidity of alter-native therapy, such as esophagectomy.


ID: 3527166OUTCOMES OF ESOPHAGEAL STENT PLACEMENT INPATIENTS WITH ASPIRATION – A NATIONAL INPATIENTSAMPLE STUDYNeethi R. Dasu*, Herman Suga, Yaser Khalid, ]C. J.nathan Foster,Lucy M. Joo, Brian BlairIntroduction: The endoscopic placement of esophageal stents is an important treat-ment modality for ill patients with comorbidities including malignant dysphagia,esophageal strictures, iatrogenic perforations, anastomotic leakage, and fistulas.However, there is minimal data on the influence of sex, race, insurance status onmortality, hospital length of stay (LOS), and total hospital charges for patients un-dergoing esophageal stent placement who suffered from aspiration events versus

patients undergoing esophageal stent placement without aspiration events. Previousstudies have identified that patients with aspiration events following esophagealstent placement have a higher incidence of mortality and complications comparedto patients without aspiration events following esophageal stent placement. The aimof this study was to identify risk factors in a national population cohort (in the USA)admitted to hospital in 2017. Methods: All patients aged 18 years and above whounderwent esophageal stent placement in 2017, were identified from the USNationwide Inpatient Sample (NIS), a large publicly available all-payer inpatient caredatabase in the USA. Multivariate regression analysis was used to estimate the oddsratios of in-hospital mortality, the average length of hospital stay, and hospitalcharges, after adjusting for age, gender, race, primary insurance payer status, hos-pital type and size (number of beds), hospital region, hospital teaching status, andother demographic characteristics. Results: Our study identified approximately 80patients (with aspiration events vs. without aspiration) who had been dischargedafter undergoing esophageal stent placement in 2017. Of these patients, 11 wereadmitted with aspiration events following esophageal stent placement versus 69without aspiration events. The analysis revealed that mortality was increased (OR 2,p < 0.043), length of stay (LOS) was increased (OR 1.74, p <0.47), and total hospitalcharges were increased (OR 1.5, p <0.813) for patients undergoing esophageal stentplacement who had aspiration events following the procedure compared to patientswithout aspiration events. Conclusion: Patients undergoing esophageal stent place-ment who had aspiration events following the procedure have increased mortality,but there was no statistically significant difference in hospital LOS or total hospitalcharges. In the future, more randomized clinical trials are required to compare thesepatient populations. The endoscopic placement of esophageal stents remains auseful treatment option however, high-quality evidence comparing specific patientpopulations is lacking, especially patients who have had prior aspiration events.

SATURDAY, MAY 22, 2021Esophagus 1Lecture

ID: 3520201POOR HEALING AND POOR SQUAMOUSREGENERATION AFTER RADIOFREQUENCY ABLATIONTHERAPY FOR EARLY BARRETT’S NEOPLASIA:INCIDENCE, RISK FACTORS AND OUTCOMESSanne Van Munster, Charlotte Frederiks*, L. Alvarez Herrero, Auke Bogte,A. Alkhalaf, B. E. Schenk, Erik.J. Schoon, Wouter Curvers, Arjun D. Koch,Steffi E. Van De Ven, P. J. F. De Jonge, Thjon J. Tang,Wouter B. Nagengast, Frans Peters, Jessie Westerhof, Martin H. Houben,Jacques Bergman, Roos E. Pouw, Bas L. WeustenIntroduction: Although endoscopic eradication therapy (EET) with radiofrequencyablation (RFA) is effective in the majority of patients with Barrett’s Esophagus(BE), a subgroup of patients is unable to achieve complete eradication of BE. Somemight experience delayed healing with visible ulcerations after RFA (“poor healing”;PH) and/or regeneration with BE mucosa (“poor squamous regeneration”; PSR).Little data is available for PH/PSR and practical recommendations are lacking. Weaimed to evaluate the incidence, risk factors, and outcomes of patients with PH/PSRafter RFA. Methods: We included all patients with at least 1 RFA treatment from anationwide registry in the Netherlands consisting of all patients who underwent EETfor early BE neoplasia. Treatments were performed by specifically trained endo-scopists according to a joint treatment and follow-up protocol. PH was defined asvisible ulcerations �3 months post-RFA; PSR as <50% regression after completehealing. Treatment success was defined as a complete eradication of BE (CE-BE).Results: 1,386 patients (median BE length C2M5) underwent EET for LGD (27%),HGD (30%), or early cancer (43%). PH occurred in 10% of patients (134/1,386)and additional time +/- acid suppression resulted in complete healing in all patients.Upon complete healing, normal squamous regeneration was seen in 50% (67/134),97% of which (65/67) achieved CE-BE. Overall, 5% of patients had PSR (74/1,386),preceded by PH in 92% (67/74). 64% (47/74) of PSR patients failed CE-BE. 70% (33/47) of failures had persisting BE that was free of neoplasia, and 30/33 underwentendoscopic follow-up. During mean 42 months, 23% (7/30) progressed to neoplasiaand all underwent curative repeat EET. The remaining 30% of failures (14/47) hadpersisting neoplasia. Overall, patients with PSR had a higher risk for progression toadvanced cancer that exceeded boundaries for endoscopic treatment as comparedto patients without PSR (15% vs. <1% resp., P<0.01). Risk factors for PSR included<50% squamous regeneration after baseline endoscopic resection (Odds ratio [OR]13.1 [95% confidence interval 6.8-25.9]), presence of reflux esophagitis (OR 7.1 [2.9-16.6]), longer BE segments (OR 1.3 [1.2-1.4]), and higher BMI (OR 1.1 [1.0-1.2]).Conclusion: PH and/or PSR occurs in 10% of patients after RFA. PH may be managedwith additional time and acid suppression. Half of the patients will then have normalsquamous regeneration with excellent success rates. However, if PSR occurs, the riskfor treatment failure and progression to advanced disease is significant. We thereforerecommend, upon detection of PSR, to carefully balance continuation of ablativetherapy versus alternative treatment options. Endoscopic surveillance is a validalternative in remaining BE with no neoplasia, whereas esophagectomy may beconsidered at early stages if advanced neoplasia is present.


Abstracts


SUNDAY, MAY 23, 2021Esophagus 1Poster

ID: 3526288IS DUODENAL INSPECTION NECESSARY INENDOSCOPIC SURVEILLANCE OF BARRETT’SOESOPHAGUS? FINDINGS FROM A TWO-CENTRE 22YEAR RETROSPECTIVE COHORT AUDITAndrew T. King*, David Nylander, Clare ParkerObjectives: There is clear evidence in endoscopic surveillance of Barrett’s oesoph-agus that thorough inspection, targeted biopsies and adherence to the Seattle bi-opsy protocol (SBP) are prerequisites to detecting dysplasia and malignancy. Thispractice together with photographic evidence of intubation of the second part of theduodenum forms part of the British Society of Gastroenterology measurable stan-dards for gastroscopy (OGD)1,2.In long Barrett’s segments, an OGD can be a pro-longed and uncomfortable procedure, especially as in the UK, where the majorityare performed with anaesthetic throat spray or Midazolam sedation. We postulatedthat if we could reduce the proportion of the surveillance OGD time spent exam-ining areas of the upper GI tract other than the oesophagus, then more time couldbe focused solely on the oesophagus. Our audit aimed to assess: � Adherence to theSBP � Occurrence of dysplasia and neoplasia � If duodenal findings led to a changein patient management Methods: All patients undergoing Barrett’s surveillance atboth the Newcastle upon Tyne (an upper GI referral centre) and South TynesideGeneral Hospitals in North East England between 1st April 2018 and 31st March 2019were identified. AK and CP interrogated case notes to identify findings from allprevious Barrett’s surveillance procedure reports from January 2008 to April 2020.They obtained details of patient demographics, adherence to SBP, histology andduodenal findings. The majority of this cohort had undergone 2-yearly surveillanceso this roughly accounts for 50% of all patients in the surveillance programme.Results: A total of 1335 endoscopies were reviewed in 390 patients. 282 (72%) weremales with an average age at diagnosis of 61; Average age at diagnosis for femaleswas 64. In 81 reports there were no reported lengths of Barrett’s and are excludedfrom the analysis.Table 1 gives percentage adherence to the SBP with the prevalenceof dysplastic or neoplastic change: *All cases of malignancy were adenocarcinoma.Duodenal inspection findings were; normal in 96.2%, duodenitis of any severity in3.4%, and clean based duodenal ulcer in 0.4%. Discussion and conclusion: Our auditdemonstrates the following 1) As the length of Barrett’s increases: � The risk of high-grade dysplasia and malignancy increases � The degree of adherence to SBP de-creases. 2) Duodenal inspection rarely found any significant pathology, and themanagement of any positive findings was superseded by the management of theBarrett’s oesophagus. We conclude that in the absence of new symptoms suggestingduodenal pathology, a dedicated Barrett’s surveillance OGD should not spend timeon duodenal inspection and should focus on careful oesophageal inspection andstrict adherence to the Seattle biopsy protocol. 1. Fitzgerald RC et al. Gut 2013;0: 1-36 2. Beg S et al. Gut 2017; 0: 1-4


ID: 3520715IS BRANCHED-CHAIN AMINO ACID-ENRICHEDENTERAL NUTRITION EFFECTIVE IN THE ENDOSCOPICTHERAPY OF ESOPHAGEAL VARICES IN ELDERLYPATIENTS?Yuichi Kojima*, Toshihisa Takeuchi, Shinya Nishida, Noriaki Sugawara,Taro Iwatsubo, Shinpei Kawaguchi, Kazuhiro Ota, Kazuhide HiguchiBackground: Fasting during the endoscopic therapy of esophageal varices may dete-riorate the nutritional statuses of patients with cirrhosis, suggesting the need fornutritional intervention to maintain the hepatic functional reserve.Objective: To examine the usefulness of branched-chain amino acid-enrichedenteral nutrition in the endoscopic therapy of esophageal varices. Methods: Of pa-tients who underwent endoscopic therapy for esophageal varices in Osaka MedicalCollege Hospital between January 2014 and September 2019, those who did not takea branched-chain amino acid (BCAA) preparation at the beginning of the treatmentwere examined retrospectively. The control, 3-day BCAA, and continued BCAAgroups include the patients who did not receive BCAA, those who orally received apack of aminoleban EN powder mix for 3 days from the day following the post-endoscopic therapy, and those who orally received a pack of aminoleban EN powdermix for the entire hospital stay from the day following the post-endoscopic therapy,respectively. Patient backgrounds and blood tests were examined by: intergroupcomparison at one week and at one month after the endoscopic therapy and tem-poral changes within each group. Those aged 65 years or older were examined asdescribed above. Results: The control group (C group): nine patients (including 8aged �65 years); the 3-day BCAA group (3-day group): sixteen patients (including 9aged �65 years); and the continued BCAA group (continued group): six patients(including 4 aged �65 years). There were no significant differences in backgroundfactors. In intergroup comparisons at one week following the endoscopic therapy,the total lymphocyte counts (TLC) in the peripheral blood in the 3-day andcontinued groups were higher than those in the C group, and the same applied forthose aged �65 years. In terms of changes over 1 week following the endoscopictherapy, no significant changes were noted in the C group, and significant im-provements in liver function and glucose tolerance were observed in the 3-day andcontinued groups. In intergroup comparisons at 1 month following the endoscopictherapy, the TLC in peripheral blood in the continued group were significantlyhigher than those in the other two groups, and the same applied for those aged �65years. In terms of changes over 1 month following the endoscopic therapy, GPT andGlu decreased significantly at 1 week, then returned to levels similar to the baselinevalues at 1 month in the 3-day group, but the effect persisted until 1 month in thecontinued group; the same applied for those aged �65 years. Conclusion: The useof a branched-chain amino acid–enriched enteral nutrient mixture in combinationwith endoscopic therapy of esophageal varices can be expected to be effective forimmunity, liver function, and glucose tolerance in elderly patients.


ID: 3524101ESOGUARD/ESOCHECK: A NOVEL, SIMPLE,OUTPATIENT TECHNOLOGY FOR THE EARLYDETECTION OF ESOPHAGEAL INTESTINALMETAPLASIA, DYSPLASIA, AND ADENOCARCINOMADavid M. Poppers*, Seth A. Gross, Dave HelmEsophageal adenocarcinoma (EAC) is a challenging malignancy, with an incidencethat has increased w6-fold annually over the past four decades. At some point, 0.5%of people in the US will be diagnosed with EAC. The incidence of EAC is 4.3/100,000with a 5-year survival rate of w19.9%, due in part to advanced stage diagnoses(w39% metastatic at time of diagnosis). Risk factors include long-standing gastro-esophageal reflux disease (GERD). The progression from intestinal metaplasia


Abstracts


(Barrett’s esophagus, BE) via dysplasia to carcinoma is incompletely understood,although both the length of the involved mucosa and certain genetic mutations andother genetic alterations have been identified. As a majority of EAC patients arediagnosed without known pre-existing Barrett’s, early detection is critical.The traditional gold standard for screening is direct optical endoscopy, although thisis underutilized. In this study, we discuss the use of a novel, simple, outpatientingestible device (EsoCheck), an catheter/inflatable balloon-based technique used inthe ambulatory setting, allowing for rapid sampling of the mucosa in the distalesophagus (Fig. 1). The procedure is typically accomplished in w3 to 5 minutes,does not require endoscopy or sedation, and is well tolerated. Collected esophagealcells are analyzed via a proprietary molecular assay (EsoGuard) for the presence ofmethylation above a defined threshold at specific sites of the vimentin and CCNA1genes, with a reported sensitivity and specificity of greater than 90% for the detec-tion of nondysplastic/dysplastic BE and EAC. In initial experience at our institutionwith a single physician user over one month, an unselected population of 99 patientsover a wide age range have undergone this procedure. 90% of whom completed theprocedure. The user learning curve was shallow, and oropharyngeal anatomic orother patient factors limited the study in only a small number of cases. Of 33 patientsfor whom results are available, the EsoGuard results were positive in 24.2%, 9.1%were unevaluable due to insufficient DNA acquisition, and the remainder werenegative (Table 1). The high throughput and yield suggest that EsoGuard/EsoCheckoffers exciting potential as a simple widespread office-based screening modality forat-risk patients. This technology may lead to earlier diagnosis and improved out-comes in patients with EAC, as a vastly greater number of patients might undergoscreening before cancer develops, when treatment options are far better – a modestincrease in screening may lead to a significant number of lives saved. These datawere accumulated by a single practitioner over only 4 weeks, indicating the potentialfor broad and rapid use in large-scale screening. Larger prospective trials areongoing to add to our early compelling findings for this simple and powerful newmodality.

Figure 1. EsoCheck Device

Table 1. Patient characteristics and interim data


ID: 3526615EFFICACY AND SAFETY OF ENDOSCOPIC FIXATION TOPREVENT MIGRATION OF ESOPHAGEAL STENTS. ATERTIARY CARE CENTER EXPERIENCEMartin Coronel*, Phillip S. Ge, Shria Kumar, Phillip Lum,Brian R. Weston, William A. Ross, Gottumukkala S. Raju,Jeffrey Lee, Emmanuel CoronelIntroduction: While mostly used for the treatment of malignant dysphagia, place-ment of fully covered esophageal self-expandable metal stents (FCSEMS) is a ther-apeutic option for the treatment of esophageal fistulas and refractory strictures. Animportant adverse event related to this device is stent migration and subsequentdysfunction or related complications. The aim of this study is to assess the safety andefficacy of different endoscopic stent fixation (ESF) techniques to prevent esopha-geal FCSEMS migration. Methods: This is a single-center retrospective study. A re-view of patients who underwent esophageal FCSEMS with ESF was performed from9/1/2017 to 9/1/2020. Once a cohort of patients was identified (nZ21), these pa-tients were matched (1:1 ratio) with a retrospective, consecutive patient cohort whounderwent esophageal FCSEMS placement without ESF (nZ21). ESF was performedusing endoscopic suturing, over the scope (OTSC) stent fix clip and hemostaticclips. The primary outcome was to identify early (<30 days) or late (>30 days) stentmigration rates in these two groups. Results: A total of 21 patients underwentFCSEMS placement with ESF were matched with 21 patients who underwentFCSEMS placement without ESF. Baseline characteristics of the two groups areshown in Table 1. In the ESF group, endoscopic suturing was used in 14 (67%)patients, OTSC stent fixation in 5 (23%), and hemostatic clips in 2 (10%) patients.The FCSEMS with ESF group showed no early stent migration and delayed migrationin 3 (14%) patients. These 3 patients had successful stent removal and in 1 patientanother stent was placed with endoscopic suturing. The FCSEMS without ESF groupshowed early migration in 1 and delayed migration in 6 (33%) (pZ0.14). In twopatients, the stents were noted to be impacted in the stomach and they could not beremoved. (Table 2) Conclusion: Endoscopic stent fixation appears to be safe andeffective. While not statistically significant, migration rates were lower in the ESFgroup without causing additional complications when compared to the FCSEMSalone group.


Abstracts



ID: 3520892EXPERIMENT ON ENDOSCOPIC BALLOON DILATIONFOR ESOPHAGEAL STENOSIS AFTER ENDOSCOPICSUBMUCOSAL DISSECTION IN PIGSSayoko Kinowaki*, Yuichi Shimizu, Masayoshi Ono, Yang ZiJian,Yusuke NIshimura, Marina Kubo, Yoshihiko Shimoda, Ikko Tanaka,Masaki Inoue, Marin Ishikawa, Keiko Yamamoto, Shoko Ono,Shunsuke Ohnishi, Naoya SakamotoBackground and Aim: Endoscopic balloon dilation (EBD) is a first choice of treat-ment for esophageal stenosis caused by endoscopic submucosal dissection (ESD).However, there has been no histological study in which the mechanism of dilation,risk of perforation during EBD and restenosis were investigated. We thereforeconducted EBD experiments on porcine esophageal stenosis models. Methods:Initially, we performed esophageal ESD with total circumference. Study 1: In dilationmodels (day 22 after ESD), the thickness of the outer muscle layer (as an index ofthe extension effect) and the area of muscle fiber bundle necrosis in the innermuscle layer (as an index of thermal damage caused by ESD) were evaluated. Twocases of muscle layer non-injury and two cases of muscle layer injury during dilationwere created. Study 2: In restenosis models (day 43 after ESD, day21 after EBD), thethickness of the fibrous plexus (as an index of restenosis) and the thickness of theentire muscular layer (as an index of recovery from muscle layer laceration) wasevaluated. Two cases of muscle layer non-injury and two cases of muscle layer injuryduring dilation were created. In total, 12 porcine models (including control models)were created. Results: Study 1: In cases of muscle layer non-injury, the thickness ofthe outer longitudinal layer of smooth muscle was 1243�322mm in surroundingrandom locations and it was 803�145mm beneath the submucosal lacera-tion(pZ0.005). In cases of muscular layer injury, it was 1248�305mm in surroundingrandom locations and it was 884�312mm on both sides of the muscle layer lacera-tion site(p<0.001). In cases of muscular layer injury, area of muscle fiber bundlenecrosis in the inner circular muscle layer was15.5�10.4�103mm2 in surroundingrandom locations and it was 40.2�12.9�103mm2 on both sides of the muscle layerlaceration site(p<0.001). Study 2: In cases of muscle layer non-injury, the thicknessof the fibrous plexus was 1359�196mm in surrounding random locations and it was1322�136mm in the laceration scar site (pZ0.74). In cases of muscular layer injury, itwas 1457�253mm in surrounding random locations and it was 1383�146mm in thelaceration scar site (pZ0.22). In cases of muscular layer injury, the thickness of theentire muscular layer was 2513�265mm in surrounding random locations and it was1107�213mm in the laceration scar site(p<0.001). Conclusion: Since thermal dam-age persists until the completion of stenosis and muscle layer which was injuredduring EBD does not completely recover afterward, EBD in the initial stage shouldbe carefully performed. An extension effect was observed only at the laceration siteand it later returned to a status similar to that of surrounding locations. Additionalintervention would be required for preventing restenosis.

SUNDAY, MAY 23, 2021Esophagus 1Lecture

ID: 3523058THE ADDITION OF WIDE-AREA TRANSEPITHELIALSAMPLING WITH THREE-DIMENSIONAL COMPUTER-ASSISTED ANALYSIS (WATS3D) TO FORCEPS BIOPSY INSCREENING EXAMS OF GERD PATIENTS WITHCOLUMNAR EPITHELIUM INCREASES DETECTION OFINTESTINAL METAPLASIAAriel E. Watts*, Swathi Eluri, Cary C. Cotton, David M. Chaletsky,Brian Moloney, Zubair A. Malik, Arvind J. Trindade, Stuart R. Gordon,Patrick Yachimski, Abraham R. Khan, Felice Schnoll-Sussman,Shervin Shafa, Michael S. Smith, Nicholas J. ShaheenBackground: Screening upper endoscopy is recommended to assess for Barrett’sesophagus (BE). When columnar epithelium is noted in the esophagus, forcepsbiopsies are performed to assess for intestinal metaplasia (IM), which is necessary todiagnose BE. Sampling error with forceps biopsies may lead to failure to detect IM,thus requiring a repeat endoscopy for confirmation of a BE diagnosis. Wide-areatransepithelial sampling with three-dimensional computer-assisted analysis(WATS3D) allows for sampling of more surface area than forceps biopsies, therebydecreasing sampling error. Its performance in increasing yield of IM during an initialendoscopy identifying esophageal columnar epithelium is poorly understood. Aim:To assess the incremental benefit of detecting IM by using WATS3D in addition toforceps biopsies in patients undergoing screening for BE who have columnarepithelium in the esophagus. Methods: The WATS3D Registry is an ongoing


Abstracts


multicenter U.S. study enrolling subjects undergoing WATS3D as part of usual careat 15 sites. Patients, aged 18 to 80, are enrolled. For this analysis, we included par-ticipants undergoing an initial screening endoscopy for gastroesophageal reflux(GERD) symptoms without a history of BE, who fulfilled endoscopic criteria for BE.To calculate the incremental yield of WATS3D in the diagnosis of BE, we selectedpatients who were found to have at least one centimeter of visible columnar mucosain the tubular esophagus. We calculated the proportion of such patients with afinding of IM on forceps biopsy. We then calculated the proportion of such patientswith IM on either FB or WATS3D. The incremental yield was defined as the pro-portion with IM on either FB or WATS3D minus the proportion with IM on FB alone.Unadjusted odds ratios were calculated for the presence of IM by either FB orWATS3D. Results: Out of 595 screening endoscopies in GERD patients withouthistory of BE, 100(18.2%) had at least one centimeter of visible columnar mucosaand were included for analysis (Table). Forty-four of these (44%) demonstrated IMby either WATS3D or forceps biopsies. WATS3D had an incremental yield of 17% forintestinal metaplasia (from 27% to 44%, Fig1) and a relative increase of 63%(17/27).With respect to dysplasia yield, WATS3D diagnosed one case of crypt dysplasia andtwo cases of high-grade dysplasia not detected on forceps biopsy. Forceps biopsyyielded two cases indeterminate for dysplasia not detected on WATS3D. Current orprior tobacco smoking and advanced age were associated with increased odds of apositive WATS3D screening. Conclusion: WATS3D, as an adjunct to forceps biopsy inscreening endoscopy for chronic GERD, can enhance the yield of IM, markedlydecreasing the need for a second endoscopy to confirm BE. The yield of IM washighest among long segment BE, among older participants, and among current orformer smokers.

Venn Diagram Comparing Yeild of Wide-Area Transepithelial Samplingwith Three-Dimensional Computer-Assisted Analysis with Area Propor-tional to Yield for Intestinal Metaplasia.


ID: 3521418LOW PREVALENCE OF SCREENING ENDOSCOPY FORBARRETT’S ESOPHAGUS IN HIGH RISK GERD PATIENTSIN A LARGE PRIMARY CARE POPULATIONSwathi Eluri*, Sumana Reddy, Corey J. Ketchem,Manaswita Tappata, Hanna G. Nettles, Ariel E. Watts,Cary C. Cotton, Evan S. Dellon, Nicholas J. ShaheenBackground: Despite societal recommendations for Barrett’s esophagus (BE)screening, it is unknown what proportion of eligible patients are screened in a pri-mary care setting. Aims: To assess the proportion of high-risk gastroesophageal re-flux disease (GERD) patients eligible for BE screening who have undergone anupper endoscopy (EGD) in a large primary care network, and to identify patient andprovider factors associated with screening. Methods: This was a retrospective studyof Caucasian, men >50 years of age with GERD conducted in a multi-practicehealthcare network consisting of 64 internal medicine (IM) and 94 family medicine(FM) practices. ACG guidelines recommend screening for men with chronic/symp-tomatic GERD and �2 other risk factors. We chose age and race as the 2 qualifyingrisk factors, as these were most reliably documented in medical records. A validatedcase definition for GERD was used: 1) �2 consecutive 1� or 2� diagnoses for GERD;2) �1 prescription for PPI, H2RA, or OTC antireflux therapy; and 3) a GERD diag-nosis 60 days before and after the index date. All patients had continuous enrollmentfor �6 months before and �1 year after the index date. Patients with known BE,other esophageal conditions, antireflux surgery, esophagectomy or Zollinger-Ellisonsyndrome were excluded. Detailed chart review was performed to obtain clinical andprocedural variables. BE was confirmed by EGD and pathology reports and definedas �1cm of columnar epithelium with intestinal metaplasia. Results: Of 1127Caucasian men >50 years of age with GERD, mean age was 65.2 � 8.6 years, 45%were obese, and 61% were smokers (Table). 73% were seeing a FP, 94% were on PPItherapy and 44% were on �1 acid suppressants. Only 39% (nZ436) had an EGD(Figure). Common procedure indications were symptomatic GERD (54%),dysphagia (25%), abdominal pain (16%), bleeding (16%), and other (17%). Only 9%were referred for BE screening as a primary indication. The prevalence of BE oresophageal adenocarcinoma (EAC) was 9.9%. Features associated with having anEGD were lower BMI (29.6 vs. 30.4), being married (74% vs. 68%), seen by a FM(67% vs, 34%), on �1 acid suppressants (52.4% vs. 38.6%), and having symptomaticGERD on treatment (78% vs. 22%), p<0.05 for all. In multivariable logistic regres-sion, factors associated with an increased odds of having an EGD were havingsymptomatic GERD on treatment (OR [95% CI] Z 12.1 [9.1-16.3]), being on �1 acidsuppressant (OR [95% CI] Z 1.4 [1.0-1.9]), and being under the care of FM (OR[95% CI] Z 1.5 [1.1-2.1]). Conclusions: In this large study to assess BE screeningrates in a high risk, non-veteran primary care population with GERD, we found thatonly 39% of eligible patients underwent an EGD. Ongoing symptoms despite ther-apy, use of >1 medication for GERD, and care by a FM doctor predicted appropriatescreening for BE.


Abstracts



ID: 3523652P53 IMMUNOHISTOCHEMISTRY REDUCES THE RATEOF INDEFINITE FOR DYSPLASIA DIAGNOSES INBARRETT’S ESOPHAGUS ASSESSMENT AND IMPROVESTHE INTEROBSERVER AGREEMENT AMONGHISTOPATHOLOGISTSWladyslaw Januszewicz*, Nastazja D. Pilonis, Richard Phillips,Maria O’Donovan, Tarek Sawas, David A. Katzka, Ahmad Miremadi,Shalini Malhotra, Monika Tripathi, Adrienn Blasko, Rebecca C. Fitzgerald,Massimiliano Di PietroBackground and Aims: A diagnosis of Barrett’s esophagus (BE) with indefinite fordysplasia (BE-IND) is made when the epithelial changes cannot be unequivocallyclassified as dysplastic. BE-IND is a subjective diagnosis with a low interobserveragreement (IOA) among pathologists. The assessment of p53 expression byimmunohistochemistry can aid in the diagnosis of dysplasia, but its role in cases ofBE-IND has not been characterized. The aim of the study was to assess the utility ofthe p53 staining in BE-IND cases. Methods: In this multicenter retrospective studywe have analyzed BE samples previously diagnosed as BE-IND from two academicreferral centers in the UK and US. The slides were reviewed by 4 GI pathologistsdivided into 2 groups (Group A and Group B), so that each individual case wasassessed independently by two different pathologists. In the first stage, hematoxylinand eosin-stained slides (H&E) were assessed. After a wash-out period of �8 weeks,the cases were reviewed again by the same pathologists with p53 immunochemistryavailable as an adjunct to guide the pathological decision (H&E+p53 diagnosis).Aberrant p53 expression was defined as either overexpression or an absent pattern.The proportion of down-graded, confirmed, and up-graded diagnoses before andafter p53 staining was calculated and compared using the McNemar’s test. IOA foreach BE grade was generated using Cohen Kappa correlation coefficients (k) forH&E and H&E+p53 diagnoses. Results: In total, 216 BE-IND tissue samples wereanalyzed. In the initial H&E assessment, the diagnosis of BE-IND was confirmed inless than half of the cases (44.0% and 32.9% in Groups A and B, respectively). Themajority of cases were down-graded to a non-dysplastic BE (NDBE); Group A: 50.5%,Group B: 59.7%. The histological diagnosis was up-graded in 5.6% of cases in GroupA (5 low-grade dysplasia [LGD], 6 high-grade dysplasia [HGD], 1 intramucosal car-cinoma [IMC]), and in 7.4% of cases in Group B (13 LGD and 3 HGD). The overallIOA for H&E diagnoses was fair with kZ0.23 (95%CI 0.12-0.34). Specifically, IOAsfor NDBE, IND, LGD and HGD/IMC were 0.31 (95%CI 0.19-0.44), 0.21 (95%CI 0.07-0.34), -0.03 (95%CI -0.50-0.43) and -0.02 (95%CI -0.64-0.60), respectively. P53expression was found aberrant in 19 cases (8.8%), equivocal in 19 cases (8.8%), andnormal in 144 cases (66.7%). The adjunct of p53 expression led to an over 40%reduction of IND diagnoses (P<.001). The IOA has increased for all BE grades,

achieving a k value of 0.46 (95%CI 0.33-0.59), 0.26 (95%CI 0.09-0.43), 0.49 (95%CI0.25-0.73), and 0.35 (95%CI -0.13-0.83) for NDBE, IND, LGD, and HGD/IMC,respectively. Conclusions: P53 immunochemistry staining reduces the rate of BE-IND diagnoses and improves the IOA among histopathologists in cases of BE withatypical epithelial changes on standard H&E.


ID: 3524488UTILIZATION OF A DEEP LEARNING ARTIFICIALINTELLIGENCE MODEL IN THE HISTOLOGICDIAGNOSIS OF DYSPLASIA IN BARRETT’S ESOPHAGUSDon C. Codipilly*, David Vogelsang, Siddharth Agarwal,Lovekirat Dhaliwal, Michele L. Johnson, Ramona Lansing,Catherine E. Hagen, Jason T. Lewis, Cadman L. Leggett,David A. Katzka, Bradley Erickson, Prasad G. IyerIntroduction: The risk of malignant transformation to esophageal adenocarcinoma(EAC) in Barrett’s esophagus (BE) increases with development of dysplasia. How-ever, the histologic diagnosis of dysplasia, particularly low-grade dysplasia (LGD), ischallenging leading to lack of interobserver agreement amongst pathologists withupto 85% of all community diagnosed LGD being downstaged upon expert GIpathologist review. This may result in unnecessary therapeutic procedures withassociated adverse effects. Hence, there is a critical need to improve diagnostic ca-pabilities to identify dysplastic BE. We aimed to leverage artificial intelligence tech-niques and utilize a deep learning model to diagnose dysplasia in BE histologicslides. Methods: We obtained non-dysplastic BE (NDBE), LGD, and high-gradedysplasia (HGD) histology slides (hematoxylin and eosin stained) from our institu-tion’s clinical pathology archive from 1992-2020. These slides were digitized (AperioAT2 Scanner, Leica Biosystems, Buffalo Grove, IL) and reviewed by at least 2gastrointestinal pathologists. Subsequently, the digitized images were annotatedwith areas of NDBE, LGD or HGD by the pathologists utilizing Aperio ImageScope(Sausalito, CA). A 1024 x 1024 pixel sliding window with 20% overlap was used togenerate patches from the annotations. The patches were resized to 224 x 224pixels. Subsequently, training, validation and test sets were created by randomlysplitting the data by patient to achieve a 70/20/10 split. We used a ResNet101 modelpre-trained on ImageNet. The model was used to predict the histology class (NDBE,LGD or HGD) on the test set by patch. For patient level prediction, a highest votescheme was used: a patient was classified as NDBE, LGD, or HGD based on thehighest grade patch prediction by the model (figure). Results: We included 587patient slides (168 NDBE, 266 LGD, and 153 HGD). These yielded 8,689 patches fortraining and 2,397 patches for validation, and a test set of 1,110 patches (224 HGD,370 LGD, 516 NDBE). Results are displayed in the table. “By patch” sensitivity andspecificity for NDBE was 93.0% and 91.9%, LGD 90.5% and 90.8%, and HGD 79.9%and 99.5%, respectively. The F1 (harmonic mean of precision and recall) for NDBEwas 92.2%, LGD was 86.8%, HGD was 88.0%. After applying the highest voteschema, “by patient” sensitivity and specificity for NDBE was 93.0% and 100%, LGDwas 99.2% and 95.3%, and HGD was 100% and 99.5%, respectively. The F1 (har-monic mean of precision and recall) for NDBE was 96.4%, LGD was 95.1%, HGD was99.4% (Table). Conclusion: We demonstrate the successful use of a deep learningmodel in accurately diagnosing BE dysplasia from histological images, with poten-tially significant improvement over current diagnostic capabilities. This model needsto be further developed and externally validated before testing its clinical utility.

Training Algorithm


Abstracts


Results Table


ID: 3521795ENDOSCOPIC EXPERT REVISION OF PREVIOUSHISTOLOGICAL CONFIRMED FLAT LOW-GRADEDYSPLASIA IN BARRETT’S ESOPHAGUSEsther Nieuwenhuis*, Sanne Van Munster, Bas L. Weusten,L. Alvarez Herrero, Auke Bogte, A. Alkhalaf, B. E. Schenk, Erik.J. Schoon,Wouter Curvers, Arjun D. Koch, Manon Spaander, Thjon J. Tang,Wouter B. Nagengast, Jessie Westerhof, Martin H. Houben,Jacques Bergman, Roos E. PouwBackground: The strongest histologic predictor for progression to high-gradedysplasia (HGD) or esophageal adenocarcinoma (EAC) in Barrett’s esophagus(BE) is expert confirmed diagnosis of low-grade dysplasia (LGD). However, previousstudies showed that up to 85% of LGD diagnosis were downstaged to non-dysplasticBE during revision. Therefore, Dutch guidelines advise to only refer patients withconfirmed LGD to a Barrett’s Expert Center (BEC). Aim was to assess if a finding ofconfirmed LGD in BE without visible lesions (VL), diagnosed in a community setting,is an indicator for higher grades of dysplasia and if referral to a BEC is indeednecessary. Methods: Endoscopic therapy for BE neoplasia in NL is centralized in 9BECs with trained endoscopists and pathologists. Upon community hospital LGDdiagnosis, a national expert pathology panel reviews biopsy specimens. If LGD isconfirmed, patients are referred for dedicated imaging endoscopy with high-defi-nition white light- and virtual chromoendoscopy, followed by target/Seattle biopsies,in a BEC <3 months. We collected data from patients with confirmed LGD inrandom biopsies, without VL, referred between Jan 2017 and Oct 2019, since theguideline was introduced in 2017. Primary outcome was worst baseline histologyestablished in a BEC, either in random biopsy specimen or in endoscopic resectionspecimen, reviewed by an expert pathologist. Results: 222 patients with confirmedLGD without detected VL were referred to a BEC. Time between community andBEC endoscopy was 3mo (IQR 0-3). In 54/222 patients (24%; 95%CI 19-31), highergrade of neoplasia was found: HGD (nZ30), EAC (nZ24). The majority of thesepatients (43; 80%) had a VL. Eleven (20%) had HGD in random biopsies. 53/54patients (98%) had curative endoscopic treatment, one patient (2%) had deepsubmucosal invasion and required esophagectomy. LGD was reconfirmed in 147patients (66%; 95%CI 60-72). In the remaining 21 patients (10%; 95%CI[6-14]) bi-opsies showed non-dysplastic BE (NDBE). The majority of LGD patients receivedendoscopic treatment (125/147;85%) of which 119 (95%) achieved completeendoscopic eradication. 20/21 NDBE and 22/147 LGD patients were not treated andunderwent surveillance. During median FU of 19mo (IQR 12-24), 3/42(7%) patientsprogressed to HGD. Conclusion: After expert panel LGD confirmation in BE withoutVL diagnosed in a community hospital, dysplasia was reproduced in >90% upon BECendoscopy. In 24% of patients, higher grades of dysplasia were found, often with VL.Our results endorse the current advice to confirm LGD, and to refer patients withconfirmed LGD, even without VL, to an expert center.

Worst histopathology outcomes at imaging endoscopy in a BEC.


ID: 3525271NEAR-INFRARED FLUORESCENCE MOLECULARENDOSCOPY SHOWS PROMISING RESULTS INDETECTING DYSPLASTIC ESOPHAGEAL LESIONS USINGTOPICALLY ADMINISTERED BEVACIZUMAB-800CW:THE PRELIMINARY RESULTS OF A PHASE 2 STUDYRuben Y. Gabriëls*, Wouter T. Hooghiemstra, Iris Schmidt,Jouke J. van der Laan, Manon Buist-Homan, Gursah Kats-Ugurlu,Dominic Robinson, Vasilis Ntziachristos, Dimitris Gkorpas,Wouter B. NagengastIntroduction: Esophageal cancer (EC) is affecting more than 450,000 people world-wide and is the 6th leading cause of cancer-related deaths. The poor EC survival isattributed to the insufficient methods for premalignant lesion detection and there-fore there is a great need for new endoscopic techniques that can visualize early-stage lesions. In 2017 our group published promising results using near infraredfluorescent molecular endoscopy (NIR-FME) against vascular endothelial growthfactor A (VEGF-A) to improve early (pre)malignant lesion detection. Here we showthe preliminary results of the phase II study. Aims & Methods: In this phase II studywe aim to evaluate the sensitivity and specificity of the tracer bevacizumab-800CW incombination with NIR-FME for detecting (pre)malignant lesions in patients withBarrett’s esophagus (BE). The tracer, Bevacizumab-800CW, was topically adminis-tered to the patients and after 5 minutes of incubation NIR-FME was performed. Toquantify the intrinsic fluorescent signal, we used multi-diameter single fiber spec-troscopy / single fiber fluorescence (MDSFR/SFF) spectroscopy measurements bothin vivo and ex vivo. In case of additional fluorescent lesions biopsies were taken toanalyze if dysplasia was present. The day after the endoscopic procedure theendoscopic mucosal resection (EMR) specimen was analyzed with widefield back-table imaging. Results/Discussion: In our preliminary results, 38 patients wereincluded and topical-based NIR-FME detected all dysplastic lesions. Visible lesionspresented with a median TBR of 2.33 � 1.07. Additionally, in 12 patients, this novelendoscopic technique identified in total 14 additional lesions which was not visu-alized by high-definition white light endoscopy (HD-WLE) and narrow band imaging(NBI) inspection. In three patients, no fluorescence was visible and histology resultsof random biopsies showed no dysplasia (nZ2) or low-grade dysplasia (nZ1).Within a subset of 23 patients spectroscopy results were analyzed. Both visible le-sions and additional lesions showed in all individual 23 patients a significantly (P <0.001) higher mean intrinsic fluorescence compared to Barrett’s tissue, 0.073 �0.015, 0.064 � 0.017, 0.018 � 0.005 respectively. In our cohort no (serious) adverseevents related to the tracer were observed. Conclusion: Based on the preliminaryresults combined with the results of the Phase I study we can conclude that VEGF-Aguided NIR-FME is able to reliably detect (pre)malignant dysplastic lesions in pa-tients with BE and seems to improves early lesion detection compared with HD-WL/NBI endoscopy. Moreover, the topically administered tracer Bevacizumab-800CW issafe and well tolerated.


Abstracts



ID: 3524509BARRETT’S ESOPHAGUS AFTER SLEEVE GASTRECTOMY:AN ANALYSIS OF INCIDENCE AND DIAGNOSTIC UPPERENDOSCOPY RATES USING STATEWIDE CLAIMS DATAEric Swei*, Shelby A. Sullivan, Jason Samuels, Laura Helmkamp,Sachin B. Wani, Frank I. Scott, Jonathan SchoenBackground and Aims: Laparoscopic sleeve gastrectomy (LSG) is the most commonbariatric surgery performed in the US and abroad. Recent studies have suggestedthat LSG is associated with the development of Barrett’s Esophagus (BE) even in theabsence of gastroesophageal reflux disease (GERD) symptoms. Despite this, there isno current consensus on performing upper endoscopy (EGD) to screen for BE inpatients who have undergone LSG. The aim of this study was to assess the rates ofEGD and incidence of new BE diagnoses in patients undergoing LSG. Methods: Thiswas a retrospective cohort study of patients who underwent LSG between 2012-2017while enrolled in the Colorado All Payer Claims Database (COAPCD), the state ofColorado’s most comprehensive source of commercial health insurance claims data.Patients were included if they had a diagnostic ICD code for obesity as well as a CPTcode specific for LSG. We identified the number of patients undergoing EGD at eachyear in a range of -8 to +8 years before or after their LSG surgery. In addition, weidentified all patients in this cohort who had a first-time diagnosis of BE within oneyear of an EGD using a combination of ICD and SNOMED codes. Time-to-eventanalysis was performed using a Kaplan-Meier approach, excluding patients who hada diagnosis of BE made either before or within one year after surgery, to estimate thecumulative post-operative incidence of new BE diagnosis. Results: We identified5,562 patients who underwent LSG between 2012-1017. Of these, 1,972 (35.5%)patients had at least one diagnostic record of EGD. The incidence rate of EGD washighest in the year immediately preceding surgery at 22.1% but decreased to 5.67%by one year after LSG (Table 1). The median annual incidence rate of EGD was2.21% [1.89-3.08%] before surgery and 4.41% [4.07%-4.67%] after surgery. Therewere 81 patients in the cohort who had a new diagnosis of BE made within one yearof an EGD over the entire study period, representing a cumulative incidence of1.45% among all patients and 4.11% among only patients who underwent EGD.However, when looking only at post-LSG incidence, the cumulative incidence of anew diagnosis of BE was 1.6% (95% CI: 0.4%-2.7%) at two years and 6.0% (95% CI:3.6%-8.4%) at five years based on Kaplan-Meier analysis (Figure 1). Analysis beyondfive years was limited due to low follow up numbers. Conclusions: In this largestatewide database, rates of EGD remained low after LSG but the incidence of a newpost-operative BE diagnosis in patients who underwent EGD was higher than in thegeneral population. These data suggest that patients undergoing LSG may havedisproportionately high risk of developing BE after surgery. More research isrequired to identify high-risk individuals who would benefit from post-operativescreening EGD.


ID: 3521940ENDOSCOPIC SUBMUCOSAL DISSECTION FORBARRETT’S RELATED NEOPLASIA IN THENETHERLANDS: RESULTS OF A NATIONWIDE COHORTOF 130 CASESEva P. Verheij*, Sanne N. Van Munster, Esther Nieuwenhuis,Laurèlle van Tilburg, Johan Offerhaus, Sybren L. Meijer,Lodewijk A. Brosens, Bas L. Weusten, A. Alkhalaf, B. E. Schenk,Erik.J. Schoon, Wouter Curvers, Steffi E. Van De Ven,Wouter B. Nagengast, Martin H. Houben, Jacques Bergman,Arjun D. Koch, Roos E. PouwIntroduction: Endoscopic resection (ER) is the standard of care for early neoplasia inBarrett’s esophagus (BE). Generally, (piecemeal) ER is used to remove earlyneoplasia, yet the use of endoscopic submucosal dissection (ESD) is expanding. We


Abstracts


aimed to report outcomes of all ESDs for BE neoplasia, performed in a setting ofcentralized care in the Netherlands. Methods: Endoscopic therapy for BE neoplasiain the Netherlands is centralized in 9 expert centers with specifically and jointlytrained endoscopists and pathologists. Uniformity is further ensured by a jointprotocol and regular group meetings. ESD is performed for large and bulky lesionsthat cannot be removed with cap-based ER and/or in case of suspicion for submu-cosal (sm) invasion. Prospectively collected treatment/FU data are registered in auniform database. We report efficacy and safety outcomes of all successfullycompleted ESD-BE cases treated in the Netherlands since 2008. En-bloc resectionwas defined as complete resection of the delineated target lesion in a single piece,R0-resection as absence of cancer in the vertical and lateral margin. Results: A total of130 ESDs was performed for lesions with a median diameter of 30mm (IQR 10-40)over 30% of the circumference (25-50). During median 121 min (90-180), 126/130were removed en-bloc (97%). The remaining 4 were completely removed inpiecemeal fashion. Pathology was m-EAC (48%) or sm-EAC (52%; 19% sm1 and 33%�sm2). Stratified for depth of invasion, the combined rate for en-bloc and R0resection was 87% for T1a lesions (95%CI 77-94) and 49% (95%CI 37-62) for T1blesions. After R1 resection, 29% of patients (10/34) had residual cancer at first FU, allof which were detected during the 8-12 weeks follow-up endoscopy. The remaining71% (24/34) had no residual cancer in esophagectomy specimen (nZ4) or during amedian endoscopic FU of 9 months (4-22) (nZ20). A total of 76 patients with en-bloc and R0 resection underwent endoscopic FU during median 17 months (IQR 8-30), with a local recurrence risk of 0% [95% CI 0-5]. In one patient, a small perfo-ration occurred (1% [95% CI 0-4]), successfully treated with a clip. Post-proceduralbleeding occurred in 4 patients (3% [ 95% CI 1-7]); esophageal stricture in 18 (13%,[95% CI 8-20]), resolved after median 3 (IQR 1-12) endoscopic dilatations.Conclusion: In expert hands, ESD is safe and allows for effective removal of mucosaland submucosal esophageal adenocarcinoma. Our data suggest that histopatholog-ical R1 resection does not necessarily imply residual cancer and need for additionalsurgery, and underline the importance of endoscopic restaging to identify patientswho do have residual cancer.

Image 1. Flow-chart residual neoplasia and recurrences after completeESD


ID: 3525809COMPARATIVE OUTCOMES OF ENDOSCOPICERADICATION THERAPY FOR DYSPLASTIC BE USINGRADIOREQUENCY ABLATION AND CRYOBALLONABLATION: A MULTICENTER PROPENSITY SCOREMATCHED COHORT STUDYSiddharth Agarwal*, Mohammad Alshelleh, Jamie Scott,Lovekirat Dhaliwal, Don C. Codipilly, Ross Dierkhising,Cadman L. Leggett, Kenneth K. Wang, Fouad Otaki, Arvind J. Trindade,Prasad G. IyerBackground: Endoscopic eradication therapy (EET) for dysplastic BE combinesendoscopic resection and ablation to achieve complete remission of dysplasia(CRD) and complete remission of intestinal metaplasia (CRIM). Level 1 evidencesupports the use of radiofrequency ablation (RFA) in reducing progression in BE-high grade dysplasia (HGD) and low-grade dysplasia (LGD). Efficacy of ablationusing the Cryoballoon ablation (CBA) system has been demonstrated in a multi-

center cohort study. Comparative outcome data between these two modalities arelacking. We aimed to assess the comparative effectiveness of these two ablationmodalities in a multicenter cohort study. Methods: Data on BE patients with LGD,HGD or intramucosal carcinoma (IMC) undergoing EET using RFA or CBA as theprimary ablation modality at three tertiary referral centers from 2014-2020 by en-doscopists experienced in BE EET were extracted. Patients treated with CBA or RFAas rescue treatment after failure of the initial ablation modality were excluded. Dataabstracted included demographic, clinical, endoscopic and histologic details. Pri-mary outcomes included the rates and predictors of CRD and CRIM in the twoablation groups. Secondary outcomes included rates of complications and recur-rence rates after CRIM in the two groups. Statistical analysis was conducted by timeto event analysis and Cox proportional hazards models. Additionally, propensityscored matched analysis was conducted matching relevant clinical variables outlinedin table 2. Results: 369 patients were included (85 in the CBA group and 284 in theRFA group). Baseline characteristics of patients in both groups are displayed in table1. Baseline characteristics were similar except for a shorter maximal BE segmentlength and lower proportion of long segment BE (LSBE) in the CBA group. Median(IQR) follow up after initial ablation was 1.5 (0.8, 2.5) years in the RFA and 2.0 (1.3,2.5) in the CBA group. While the rate of CRIM in the CBA group was higher at 2years, on a multivariable model adjusting for baseline clinical and histological vari-ables, the odds of reaching CRD and CRIM was not influenced by the ablationmodality. (Table 2) Results of a propensity score matched analysis (85 CBA and 85RFA cases) revealed comparable results for achieving CRD (CBA vs RFA HR (95% CI):1.16 (0.81-1.65), pZ0.42) and a trend towards higher probability of reaching CRIMwith CBA (CBA vs RFA HR (95% CI): 1.45 (0.99-2.11), pZ0.05). The rate of com-plications and recurrence in the two groups were comparable (table 1). Conclusions:We demonstrate largely comparable histological and safety outcomes with EET fordysplastic BE using CBA and RFA, with a non-significant trend for CRIM in the CBAgroup on propensity score analysis. A randomized trial between these two modal-ities is needed to definitively compare these two modalities.

Table 1. Baseline characteristics and outcomes in the radiofrequencyablation (RFA) and cryoballoon ablation (CBA) groups


Abstracts


Table 2. Multivariable model of predictors of reaching CRIM in the twoablation groups (RFA and CBA).


ID: 3522400SIMPLIFED VERSUS STANDARD RADIOFREQUENCYABLATION PROTOCOLS FOR DYSPLASTIC BARRETT’SESOPHAGUS: A SYSTEMATIC REVIEW AND META-ANALYSISSagar Shah*, Mary Kathryn Roccato, Samuel S. Ji, Neil Jariwalla,Spencer Kozik, Ronald D. Ortizo, Jennifer M. Kolb, Jason B. SamarasenaIntroduction: Radiofrequency ablation (RFA) is a well established technique for thetreatment of Barrett’s Esophagus (BE). Standard RFA protocols typically include twoablations, followed by a cleaning step, followed by an additional two ablations.During the cleaning step, the electrode is removed and cleaned and debris isscraped from the esophageal mucosa. Simplified protocols that omit a cleaningphase between ablations have demonstrated similar efficacy to standard protocolsthat include the interposed cleaning phase. Some concern exists that simplifiedprotocols may come at the cost of higher esophageal stricture rates. In this study, weaimed to assess whether both simplified and conventional protocols achievedcomplete eradication of intestinal metaplasia (CR-IM) and complete eradication ofdysplasia (CR-D) at similar rates, and if either protocol was associated with a higherrate of stricture formation. Methods: A literature search was performed acrossmultiple databases, including MEDLINE/PubMed, The Cochrane Library and GoogleScholar (September of 2020). Studies comparing RFA protocols that omitted acleaning step (simplified) and protocols that included a cleaning step (standard)were eligible for inclusion. The outcomes examined included the rate of CR-IM, CR-D and stricture formation. Results: Ten studies were included in the meta-analysis,representing 919 patients treated with standard protocols and 715 treated withsimplified protocols. The two randomized controlled trials included were deemed tobe of high quality using the Cochrane Risk of Bias tool. The eight cohort studieswere deemed to be of high quality, with a median New-Castle Ottawa scale score of 7(range: 7-9). At baseline, three studies reported differences in the proportion ofpatients that received endoscopic mucosal resection (EMR) of nodular lesions priorto RFA. There was no statistically significant difference in achievement of CR-IM (OR,1.21; 95% CI, 0.86-1.69; PZ0.27, I2 Z 0%) or CR-D (OR, 1.16; 95% CI, 0.72-1.86;PZ0.54, I2 Z 0%). Simplified protocols were associated with an increased rate ofstricture formation (OR, 2.17; 95% CI, 1.49-3.17; P<0.001, I2 Z 18%). Discussion:The results of the present systematic review and meta-analysis provide strong evi-dence for the non-inferiority of simplified RFA protocols in the treatment of Barrett’sEsophagus. Specifically, omission of an interposed cleaning step does not appear toreduce rates of eradication of intestinal metaplasia or dysplasia. However, there is ademonstrable association between simplified protocols and stricture formation thatwarrants caution and further adequately controlled investigation.

Figure 1. Forrest plot for pooled estimates of CR-IM (top), CR-D (mid-dle), and stricture formation (bottom) rate following RFA using eitherstandard or simplified protocols


ID: 3524312OUTCOMES FOR ENDOSCOPIC RESECTION OF T1BESOPHAGEAL ADENOCARCINOMA: A SYSTEMATICREVIEW AND META-ANALYSISDon C. Codipilly*, Apoorva K. Chandar, Lovekirat Dhaliwal,Amitabh Chak, Kenneth K. Wang, Prasad G. IyerIntroduction: The management of T1b esophageal adenocarcinoma (EAC) has tradi-tionally involved esophagectomy, a procedure associated with mortality and sub-stantial morbidity. The development of endoscopic eradication therapy (EET),combining endoscopic resection with ablation, has provided an alternative methodfor management of these cancers in select patients with low risk features. In thissystematic review and meta-analysis, we aimed to assess outcomes for patients withT1b EAC undergoing EET. Methods: We systematically queried scientific databasesfor reports of outcomes of EET in patients with T1b EAC from 2000-2020. Data wereabstracted from studies meeting a priori set inclusion criteria. We performed a sin-gle-arm meta-analysis to generate summary estimates using a fixed effects model.Our primary outcomes of interest were EAC remission rates (defined as subsequentendoscopic surveillance histology negative for EAC within 12 months of initial pro-cedure) and cumulative EAC-specific mortality. Secondary outcomes included 5-yearEAC specific mortality and cumulative EAC recurrence. We further analyzed theseoutcomes in a subset of patients with low risk disease (those with all of thefollowing: G1/G2 differentiation, disease limited to sm1, and no lymphovascularinvasion). Results: We identified 18 studies contributing various data points towardsour outcomes of interest, encompassing 447 patients with median follow up rangingfrom 5-72 months. Meta-analysis outcomes are shown in Table 1. Meta-analysis of 6studies with 183 patients demonstrated an EAC remission rate of 73.3%. Meta-analysis of 6 studies with 254 patients showed a cumulative EAC mortality rate of5.7% over a median follow up ranging from 18-72 months. Meta-analysis of 3 studieswith 98 patients demonstrated a 5 year EAC-specific mortality of 11.4%. Meta-analysisof 14 studies with 359 patients demonstrated a cumulative EAC recurrence rate of11.1% over a median follow up ranging from 5-72 months.We also assessed outcomes in patients with low risk disease (table 2). Meta-analysisof 5 studies with 106 low risk patients demonstrated an EAC remission rate of 81.9%.Meta-analysis of 3 studies with 82 low risk patients showed a cumulative EAC mor-tality rate of 1.4% over a median follow up ranging from 18-72 months. Only 1 studyprovided 5 year EAC specific mortality for low risk disease and reported a rate of 0%.Meta-analysis of 10 studies with 163 low risk patients demonstrated a cumulativeEAC recurrence rate of 7.4% over a median follow up of 10-70 months. Conclusion:EET can be effective for treatment of T1b EAC with low risk histology, resulting infavorable outcomes related to remission, cancer-specific mortality, and recurrence.For patients with T1b EAC who do not meet low risk criteria EET should be reservedonly for those who are poor surgical candidates.


Abstracts



ID: 3524554IMPROVED QUALITY OF LIFE AFTER ENDOSCOPICTHERAPY FOR BARRETT’S ESOPHAGUS AND EARLYESOPHAGEAL CANCERThurarshen Jeyalingam*, Matthew Woo, Stephen E. Congly,Joel David, Paul J. Belletrutti, Milli GuptaBackground: In patients with Barrett’s esophagus (BE), endoscopic therapy reducesthe risk of progression to invasive esophageal adenocarcinoma (EAC). Data on theimpact of endoscopic therapy on patient quality of life (QoL) is limited. Aims: Weaimed to assess: (1) change in QoL during the course of endoscopic therapy for BE,(2) factors which predict this change, (3) whether achieving complete remission ofdysplasia (CRD) or intestinal metaplasia (CRIM) affect the degree of change.Methods: We conducted a retrospective observational study using a prospectivelymaintained database of BE patients treated in Calgary, Alberta from 2013-2020containing data on demographics, BE disease characteristics and therapeutic inter-ventions, QoL, and follow-up. QoL was determined prior to initiation of therapy andafter each treatment session using a previously validated visual analogue scalequestionnaire. These responses were converted to a QoL score out of 10, wherehigher scores indicate worse QoL. Descriptive statistics were calculated and changein QoL was compared using a Wilcoxon signed ranks test. Backwards multiple linearregression analysis was performed to determine predictors of change in QoL.Results: Of 130 BE patients, 112 (86.1%) were male and 104 (80%) had dysplastichistology or intramucosal carcinoma on index endoscopy (Table 1). Mean (SD)age was 65.6 (12.0) years. At time of analysis, 76 patients (58.5%) had completedendoscopic therapy, of whom 69 (90.8%) achieved CRIM; 54 patients (41.5%) werestill undergoing treatment. Prior to treatment, the most significantly affected QoLmeasure was “degree of unsatisfaction with condition of the esophagus”, which hada mean score of 4.65. There was significant improvement in all QoL measures duringthe treatment course except for “depression” (Table 2). Patients with CRIM or CRDhad reductions in “sleep difficulty” and “negative impact on life” to a significantlygreater degree vs patients not achieving CRIM (D sleep -0.45 vs 0.0, PZ0.002; Dnegative impact -0.4 vs -0.05, PZ0.014) or CRD (D sleep -0.40 vs +0.60, PZ0.002; D

negative impact -0.40 vs +0.20, PZ0.04). Multiple linear regression revealed olderage (BZ-0.03, PZ0.008) and fewer number of EMR sessions (BZ0.254, PZ0.008)were correlated with greater improvement in QoL. Conclusions: Endoscopic therapyimproves QoL in BE patients, especially in those achieving CRIM or CRD. Older ageand fewer EMRs during the treatment course are correlated with greater improve-ment in QoL. These results further reinforce the role of endoscopic therapy as thefirst-line treatment of BE and early EAC.


ID: 3521739RANDOMIZED STUDY OF TWO ENDO-KNIVES FOR THETRACTION-ASSISTED ENDOSCOPIC SUBMUCOSALDISSECTION OF ESOPHAGEAL CANCERYoshiyasu Kitagawa*, Rino Nankinzan, Takuto SuzukiBackground and Aims: Endoscopic submucosal dissection (ESD) is an accepted andestablished treatment procedure for early-stage esophageal cancer; however, it istechnically difficult. To perform ESD safely and more efficiently, researchers devel-oped the clip-with-line traction method. Needle-type devices, such as the Dual knife,have demonstrated favorable results for traction-assisted esophageal ESD (Fig. 1).However, esophageal ESD can still cause injury to the muscularis propria, and itrequires a prolonged operation time. Recently, an improved model of the IT knife(IT knife nano) has become available to be used for both incisions and dissections,and it is well suited for esophageal and colonic lesions (Fig. 1). It has a long arm thatallows rapid dissection, and an insulated tip to avoid inadvertent injury to themuscular layer. This knife may allow a faster and easier ESD than the Dual knife. Thisstudy aimed to compare the performances of the Dual knife and IT knife nano interms of swiftness and safety when used in traction-assisted esophageal ESD.Methods: From July 2018 to July 2020, 50 patients with early-stage esophageal cancer


Abstracts


were prospectively enrolled through randomization using a computer-generatedrandom sequence stratified by tumor size, tumor location, esophageal circumfer-ence, and operator. Three endoscopists, who had gained experience in at least 50esophageal and 200 gastric ESD procedures, performed all the procedures. Theprimary outcome was the total procedure time, whereas the secondary outcomeswere submucosal-dissection time, en bloc and complete resection rates, perforationrate, and adverse events. Results: The patients were equally divided into two groups:the Dual knife group (D-group) and the IT knife nano group (I-group). The baselinecharacteristics were well balanced between the 2 groups (Table 1). The I-group hadsignificantly shorter total procedure time (31 [11–88] minutes vs. 48 [21–167] mi-nutes; P < 0.01) and submucosal-dissection time (11 [4–54] minutes vs. 27 minutes[7–118]; P < 0.01) than the D-group. The en bloc and complete resection rates weresufficiently high in both groups (100 and 100% in the D-group and 100 and 96% inthe I-group, respectively). Additionally, significantly fewer hemostatic procedurescaused by intraoperative bleeding were performed in the I-group than in the D-group (0 [0–2] vs. 1 [0–6]; P < 0.01). Muscular layer exposure was observed in 20%of patients in the D-group and only 8% in the I-group, though the difference wasinsignificant (P Z 0.42). Moreover, delayed bleeding, perforation, or esophagealstricture did not occur in either group. Conclusion: The IT knife nano exhibitedlower procedure and submucosal-dissection times of traction-assisted esophagealESD and lesser adverse events than the Dual knife.


Abstracts


ESOPHAGUS 1 - Gastroenterology

Documents

Transcript of ESOPHAGUS 1 - Gastroenterology