Comparison of endoscopic mucosal resection versus endoscopic submucosal dissection for Barrett's neoplasia and esophageal adenocarcinoma: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are both accepted resection strategies for Barrett's esophagus-related neoplasia and esophageal adenocarcinoma (EAC). However, a lack of consensus exists regarding which technique offers superior outcomes. This study aims to systematically review the evidence comparing EMR versus ESD in treating Barrett's neoplasia and EAC. METHODS: We searched 3 databases (Embase, MEDLINE, Cochrane Central) through October 2023. We included studies comparing the efficacy of EMR and ESD for Barrett's neoplasia and EAC. Primary outcomes include en bloc, R0, and curative resection; complete remission of dysplasia (CRD), and local recurrence. Secondary outcomes encompass adverse events. RESULTS: Our search identified 905 records. Eleven studies were included in the final analyses. Data showed significantly higher en bloc resection rates with ESD (odds ratio [OR], 31.53; 95% confidence interval [CI], 10.02-99.19; P < .01; 7 studies). R0 resection rates were significantly higher with ESD (OR, 5.92; 95% CI, 2.75-12.77; P < .01; 8 studies). Curative resection rates tended to be higher with ESD (OR, 3.49; 95% CI, 0.86-14.14; P = .080; 4 studies). There was no significant difference in CRD rates (OR, 0.92; 95% CI, 0.37-2.26; P = .86; 3 studies). Local recurrence rates tended to be lower with ESD (OR, 0.35; 95% CI, 0.11-1.04; P = .058; 10 studies). As for adverse events, there was no significant difference in bleeding, perforation, and postoperative stricture rates. CONCLUSIONS: This systematic review and meta-analysis demonstrates that ESD achieves higher en bloc, R0, and curative resection rates, with a tendency toward lower recurrence rates. These results suggest that ESD may be a more effective option for managing Barrett's neoplasia and EAC. (International Prospective Register of Systematic Reviews [PROSPERO] registration number: CRD42023426486.).

Establishment of standards for the referral of large nonpedunculated colorectal polyps: an international expert consensus using a modified Delphi process.

BACKGROUND AND AIMS: Resection of colorectal polyps has been shown to decrease the incidence and mortality of colorectal cancer. Large nonpedunculated colorectal polyps are often referred to expert centers for endoscopic resection, which requires relevant information to be conveyed to the therapeutic endoscopist to allow for triage and planning of resection technique. The primary objective of this study was to establish minimum expected standards for the referral of large nonpedunculated colonic polyps for potential endoscopic resection. METHODS: A Delphi method was used to establish consensus on minimum expected standards for the referral of large colorectal polyps among a panel of international endoscopy experts. The expert panel was recruited through purposive sampling, and 3 rounds of surveys were conducted to achieve consensus. Quantitative and qualitative data were analyzed for each round. RESULTS: A total of 24 international experts from diverse continents participated in the Delphi study, resulting in consensus on 19 statements related to the referral of large colorectal polyps. The identified factors, including patient demographic characteristics, relevant medications, lesion factors, photodocumentation, and the presence of a tattoo, were deemed important for conveying the necessary information to therapeutic endoscopists. The mean scores for the statements, which were scored on a scale of 1 to 10, ranged from 7.04 to 9.29, with high percentages of experts considering most statements as a very high priority. Subgroup analysis according to continent revealed some variations in consensus rates among experts from different regions. CONCLUSIONS: The identified consensus statements can aid in improving the triage and planning of resection techniques for large colorectal polyps, ultimately contributing to the reduction of colorectal cancer incidence and mortality.

Recurrence following successful eradication of neoplasia with endoscopic mucosal resection compared with endoscopic submucosal dissection in Barrett's esophagus: a retrospective comparison.

BACKGROUND: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are effective treatments for Barrett's neoplasia. However, little is known about recurrence rates following these techniques. We compared long-term neoplasia recurrence rates following EMR and ESD. METHODS: This study included patients with Barrett's neoplasia (high grade dysplasia/adenocarcinoma) treated between July 2019 and December 2023 at a tertiary referral center in Canada. Outcomes were residual neoplasia at first follow-up, complete remission of neoplasia (CRN), and neoplasia recurrence following CRN. RESULTS: 157 patients were included (87 EMR, 70 ESD). Compared with EMR, the ESD group had larger lesions (median 2 vs. 3 cm, P<0.05), more adenocarcinoma (85.1% vs. 94.3%, P = 0.07), and deeper submucosal invasion (T1a: 71.6% vs. 75.8%; T1b-SM1: 25.7% vs. 6.1%; T1b≥SM2: 2.7% vs. 18.2%; P<0.05). Among 124 patients with follow-up (71 EMR, 53 ESD), 84.9% of ESD-treated patients had curative resections (i.e. R0 resection with low risk for lymph node metastasis), whereas 94.4% of EMR-treated patients had deep margin R0 resection of low risk lesions. At first follow-up, residual neoplasia (14.1% vs. 11.3%) and CRN (97.2% vs. 100%) were similar in the EMR and ESD groups, but neoplasia recurrence following CRN was significantly higher with EMR (13% vs. 1.9%, P<0.05), with cumulative probability of recurrence at 3 years of 18.3% vs. 4.2%, respectively. CONCLUSIONS: Neoplasia recurrence following CRN was significantly higher following EMR compared with ESD, suggesting that ESD may be superior to EMR in preventing neoplasia recurrence in Barrett's esophagus.

Association of gastric myotomy length in peroral endoscopic myotomy (POEM) with gastro-esophageal junction distensibility measured by Endoluminal Functional Lumen Imaging Probe (EndoFLIP).

BACKGROUND: Endoluminal Functional Lumen Imaging Probe (EndoFLIP) is a device that measures gastro-esophageal junction (GEJ) distensibility. However, it is not demonstrated that GEJ distensibility increases proportionally with varying gastric myotomy length in peroral endoscopic myotomy (POEM). This study aimed to investigate the association between gastric myotomy length in POEM and intraoperative EndoFLIP findings. METHODS: This single-center, retrospective cohort study included patients who underwent POEM with intraoperative EndoFLIP from December 2019 to January 2023. Using EndoFLIP, minimal balloon diameter and its distensibility index (DI) were measured pre- and post-myotomy. Primary and secondary outcomes were the post-myotomy EndoFLIP findings at 30 ml and 40 ml volume fills. RESULTS: The study included 44 patients (mean age 53.1 years, 50% female). Chicago classification included achalasia type I (39%), II (41%), III (9%), hypercontractile esophagus (2%), and EGJOO (9%). The mean esophageal myotomy length was 7.5 ± 2.2 cm and gastric myotomy was 2.1 ± 0.6 cm. Simple linear regression analyses indicated that for each 1 cm increase in gastric myotomy length, the DI at 30 ml volume fill was estimated to increase by 2.0 mm2/mmHg (p < 0.05, R2 = 0.41), the minimal diameter at 30 ml volume fill was estimated to increase by 2.4 mm (p < 0.05, R2 = 0.48), and the minimal diameter at 40 ml volume fill was estimated to increase by 1.3 mm (p < 0.05, R2 = 0.09). CONCLUSIONS: This study demonstrates a significant linear relationship between gastric myotomy length and GEJ distensibility measured by EndoFLIP during POEM. These findings may be useful in clinical practice by enabling EndoFLIP to help calibrate a desired gastric myotomy length to achieve optimal DI and minimal diameter.

The Toronto Upper Gastrointestinal Cleaning Score: a prospective validation study.

BACKGROUND : Assessment of mucosal visualization during esophagogastroduodenoscopy (EGD) can be improved with a standardized scoring system. To address this need, we created the Toronto Upper Gastrointestinal Cleaning Score (TUGCS). METHODS : We developed the TUGCS using Delphi methodology, whereby an international group of endoscopy experts iteratively rated their agreement with proposed TUGCS items and anchors on a 5-point Likert scale. After each Delphi round, we analyzed responses and refined the TUGCS using an 80 % agreement threshold for consensus. We used the intraclass correlation coefficient (ICC) to assess inter-rater and test-retest reliability. We assessed internal consistency with Cronbach's alpha and item-total and inter-item correlations with Pearson's correlation coefficient. We compared TUGCS ratings with an independent endoscopist's global rating of mucosal visualization using Spearman's ρ. RESULTS : We achieved consensus with 14 invited participants after three Delphi rounds. Inter-rater reliability was high at 0.79 (95 %CI 0.64-0.88). Test-retest reliability was excellent at 0.83 (95 %CI 0.77-0.87). Cronbach's α was 0.81, item-total correlation range was 0.52-0.70, and inter-item correlation range was 0.38-0.74. There was a positive correlation between TUGCS ratings and a global rating of visualization (r = 0.41, P = 0.002). TUGCS ratings for EGDs with global ratings of excellent were significantly higher than those for EGDs with global ratings of fair (P = 0.01). CONCLUSION : The TUGCS had strong evidence of validity in the clinical setting. The international group of assessors, broad variety of EGD indications, and minimal assessor training improves the potential for dissemination.

Clinical and pathological predictors of failure of endoscopic therapy for Barrett's related high-grade dysplasia and early esophageal adenocarcinoma.

BACKGROUND AND AIMS: Multimodal endoscopic treatment for Barrett's esophagus (BE) related high-grade dysplasia (HGD) and early esophageal adenocarcinoma (EAC) is safe and effective. However, there is a paucity of data to predict the response to endoscopic treatment. This study aimed to identify predictors of failure to achieve complete eradication of neoplasia (CE-N) and complete eradication of intestinal metaplasia (CE-IM). METHODS: We performed a retrospective analysis of prospectively collected data of all HGD/EAC cases treated endoscopically at a tertiary referral center. Only patients with confirmed HGD/EAC from initial endoscopic mucosal resection (EMR) were included. Potential predictive variables including clinical characteristics, endoscopic features, and index histologic parameters of the EMR specimens were evaluated using multivariate Cox regression. RESULTS: A total of 457 patients were diagnosed with HGD/EAC by initial EMR from January 2008 to January 2019. Of these, 366 patients who underwent subsequent endoscopic treatment with or without RFA were included. Cumulative incidence rates at 3 years for CE-N and CE-IM were 91.4% (95% CI 87.8-94.2%) and 66.8% (95% CI 61.2-72.3%), respectively during a median follow-up period of 35 months. BE segment of 3-10 cm (HR 0.45; 95% CI 0.36-0.57) and > 10 cm (HR 0.25; 95% CI 0.15-0.40) were independent clinical predictors associated with failure to achieve CE-N. With respect to CE-IM, increasing age (HR 0.88; 95% CI 0.78-1.00) was another predictor along with BE segment of 3-10 cm (HR 0.37; 95% CI 0.28-0.49) and > 10 cm (HR 0.15; 95% CI 0.07-0.30). Lymphovascular invasion increased the risk of CE-N and CE-IM failure in EAC cases. CONCLUSION: Failure to achieve CE-N and CE-IM is associated with long-segment BE and other clinical variables. Patients with these predictors should be considered for a more intensive endoscopic treatment approach at expert centers.

Endoscopic treatment of Barrett's esophagus: What can we learn from the Western perspective?

The incidence of Barrett's esophagus (BE)-related neoplasia in Western countries has increased in the past several decades and, even in Eastern countries, it appears to be increasing. Endoscopic therapies are the first-line treatment for BE-related neoplasia; however, there is still no standardized treatment strategy. Most of the data have been published from Western countries where the ultimate goal of treatment is complete eradication of BE mucosa removing subtle synchronous lesions and preventing metachronous neoplasia. A multimodality approach that combines endoscopic resection and radiofrequency ablation (RFA) has been widely accepted in the West. In contrast, the lack of access to RFA treatment in the East has meant that endoscopic resection is the only feasible option. There is a wide divergence in treatment strategies for BE-related neoplasia between the East and the West. It is very important to consider these basic differences in the context of the currently available evidence to date. Therefore, the purpose of this article is to review the recent literature and to provide an overview of the endoscopic treatment options for BE.

Increased Intestinal Permeability in Relatives of Patients With Crohn's Disease Is Not Associated With Small Bowel Ulcerations.

BACKGROUND & AIMS: Many first-degree relatives of patients with Crohn's disease (CD) have increased intestinal permeability. Video capsule endoscopy (VCE) is the most sensitive imaging test to identify small bowel mucosal lesions that could indicate subclinical CD. We aimed to estimate the association of increased intestinal permeability with small bowel ulcerations detectable by VCE in healthy first-degree relatives of patients with CD. METHODS: We conducted a cross-sectional study of 223 healthy, asymptomatic first-degree relatives of patients with CD (parents, siblings, and children; 9-45 years old) enrolled at the University of Alberta between 2009 and 2012. Patients were given the lactulose and mannitol test to measure small bowel permeability; we used high-performance liquid chromatography to measure concentrations of lactulose and mannitol in urine samples (increased permeability defined as a ratio of lactulose/mannitol 0.025 or greater). Patients with increased permeability (n = 39) and randomly selected subjects with normal permeability (n = 59) were then examined by VCE for signs of small bowel inflammation and subclinical CD. The prevalence of small bowel lesions was compared among groups. We performed logistic regression analyses to estimate odds ratios for the association of small bowel ulcerations with intestinal permeability. RESULTS: Among 223 first-degree relatives of patients with CD, 30% were found to have increased intestinal permeability; VCE examination found 24% of subjects to have 3 or more small bowel ulcers. Three or more small bowel ulcers were detected in 28% of patients with increased intestinal permeability and 20% of patients with normal intestinal permeability (P = .37). The adjusted odds ratio for the association of 3 or more small bowel ulcers with increased intestinal permeability was 1.5 (95% confidence interval, 0.6-3.8; P = .46). CONCLUSIONS: Thirty percent of healthy, asymptomatic first-degree relatives of patients with CD have increased intestinal permeability. However, a strong association of small bowel ulceration seen on VCE with increased intestinal permeability was not observed.

Small bowel enteroscopy.

Over the past decade, the advent of capsule endoscopy and balloon-assisted enteroscopy has revolutionized the approach to small intestinal diseases. The small bowel is no longer out of reach, and has fallen within the diagnostic and therapeutic realm of the gastrointestinal endoscopist. Double-balloon enteroscopy was the first type of balloon-assisted endoscopy and is the method for which there are the most data. Single-balloon enteroscopy has since been introduced as an alternative balloon-assisted method, followed more recently by the development of spiral overtube-assisted enteroscopy. The purpose of the present article is to review these methods of small bowel enteroscopy and to discuss the latest developments. While the investigation of small bowel diseases cannot be addressed without considering the central role of capsule endoscopy, a detailed assessment is beyond the scope of the present article, and capsule endoscopy will only be discussed as it pertains to enteroscopy.

Canadian Digestive Health Foundation Public Impact Series 5: Pancreatitis in Canada. Incidence, prevalence, and direct and indirect economic impact.

The Canadian Digestive Health Foundation initiated a scientific program to assess the incidence, prevalence, mortality and economic impact of digestive disorders across Canada in 2009. The current article presents the updated findings from the study concerning pancreatitis.

Hyperamylasemia and pancreatitis following spiral enteroscopy.

BACKGROUND: Acute pancreatitis is a significant potential complication with double-balloon enteroscopy. Hyperamylasemia is frequently observed after both double-balloon enteroscopy and single-balloon enteroscopy but often without associated pancreatitis. Whether the same phenomenon occurs with spiral enteroscopy is currently unknown. AIMS: To determine the incidence of pancreatitis and hyperamylasemia following spiral enteroscopy. METHODS: A prospective cohort study of consecutive patients undergoing proximal spiral enteroscopy was conducted. Serum amylase levels were measured immediately before and following the procedure, combined with observation for clinical signs of pancreatitis. RESULTS: A total of 32 patients underwent proximal spiral enteroscopy, with a mean total procedure time of 51 min (range 30 min to 100 min) and mean depth of insertion of 240 cm (range 50 cm to 350 cm). The diagnostic yield was 50%, with 31% of all procedures being therapeutic. While no patients exhibited signs that raised suspicion of pancreatitis, hyperamylasemia was common (20%). Hyperamylasemia was not significantly associated with procedure duration or depth of insertion but was linked to patients with Peutz-Jeghers syndrome and with the use of propofol sedation, suggesting that it may be more common in difficult cases. CONCLUSIONS: Postprocedural hyperamylasemia occurred frequently with proximal spiral enteroscopy, while no associated pancreatitis was observed. This finding suggests that hyperamylasemia may not necessarily reflect pancreatic injury nor portend a risk for pancreatitis.

Retrograde double balloon enteroscopy: comparing performance of solely retrograde versus combined same-day anterograde and retrograde procedure.

OBJECTIVE: Retrograde double balloon enteroscopy (DBE) is important for evaluating the distal small bowel, but it is more challenging compared to the oral route. Optimizing small bowel insertion may enhance the diagnostic utility of the examination. We sought to determine if insertion depths achieved with retrograde DBE when performed as an isolated procedure differed significantly from when performed immediately following anterograde DBE. MATERIAL AND METHODS: A retrospective analysis was conducted of all retrograde DBE procedures performed at our center with comparisons made between "distal-only" DBE without preceding anterograde DBE and "combined" DBE after a prior same-day anterograde DBE. RESULTS: Two hundred ninety retrograde DBE procedures were performed in 264 patients over 5 years. Success of terminal ileal intubation exceeded 95%. The mean insertion depth into the distal small bowel differed significantly with 112 cm (95% CI 95-129) in the "distal-only" group and 92 cm (95% CI 85-98) in the "combined" group (p = 0.01), with a trend toward a corresponding increased diagnostic yield of 48% versus 37%, respectively (p = 0.15). Multivariate regression analysis identified both insertion route strategy (distal-only > combined; p = 0.01) and type of DBE endoscope (diagnostic > therapeutic; p = 0.02) as significant predictors of retrograde insertion depth. CONCLUSIONS: The insertion depth of retrograde DBE is significantly greater when carried out as a separate distal procedure and not in combination with a preceding anterograde DBE, and when performed using a diagnostic as opposed to the therapeutic DBE endoscope. This increased retrograde depth of insertion may be associated with an increased diagnostic yield.

Double balloon enteroscopy and capsule endoscopy for obscure gastrointestinal bleeding: an updated meta-analysis.

BACKGROUND AND AIM: Uncertainty remains about the best test to evaluate patients with obscure gastrointestinal bleeding (OGIB). Previous meta-analyses demonstrated similar diagnostic yields with capsule endoscopy (CE) and double balloon enteroscopy (DBE) but relied primarily on data from abstracts and were not limited to bleeding patients. Many studies have since been published. Therefore, we performed a new meta-analysis comparing CE and DBE focused specifically on OGIB. METHODS: A comprehensive literature search was performed of comparative studies using both CE and DBE in patients with OGIB. Data were extracted and analyzed to determine the weighted pooled diagnostic yields of each method and the odds ratio for the successful localization of a bleeding source. RESULTS: Ten eligible studies were identified. The pooled diagnostic yield for CE was 62% (95% confidence interval [CI] 47.3-76.1) and for DBE was 56% (95% CI 48.9-62.1), with an odds ratio for CE compared with DBE of 1.39 (95% CI 0.88-2.20; P = 0.16). Subgroup analysis demonstrated the yield for DBE performed after a previously positive CE was 75.0% (95% CI 60.1-90.0), with the odds ratio for successful diagnosis with DBE after a positive CE compared with DBE in all patients of 1.79 (95% CI 1.09-2.96; P = 0.02). In contrast, the yield for DBE after a previously negative CE was only 27.5% (95% CI 16.7-37.8). CONCLUSIONS: Capsule endoscopy and double balloon enteroscopy provide similar diagnostic yields in patients with OGIB. However, the diagnostic yield of DBE is significantly higher when performed in patients with a positive CE.

Single-balloon-assisted colonoscopy in patients with previously failed colonoscopy.

BACKGROUND: Despite advances in training and equipment, complete colonoscopy fails, even in experienced hands, in up to 10% of cases. Double-balloon endoscopy (DBE) has been successfully used to complete colonoscopy in these patients. Single-balloon endoscopy (SBE) has become established for small-bowel enteroscopy. However, it has yet to be studied for use in colonoscopy. OBJECTIVE: To assess the efficacy, performance, and safety of single-balloon colonoscopy. DESIGN: Prospective cohort study. SETTING: Academic tertiary referral center. PATIENTS: Patients with previously failed conventional colonoscopy. RESULTS: 23 single-balloon colonoscopy procedures were performed in 22 patients: median age 53 (range 19-75) years; 14 females, 8 males. SBE colonoscopy succeeded in cecal intubation in 22 (96%) procedures, with a median total procedure time of 30 (range 20-60) minutes. SBE colonoscopy was normal in 9 cases but resulted in a positive diagnosis in 13 (57%) procedures, including polyps (n = 6), active Crohn's disease (n = 4), Crohn's-related stricture (n = 1), and diverticulosis (n = 2). Seven (30%) procedures were therapeutic including 1 case with balloon dilation and 6 cases with polypectomy. No complications were encountered. LIMITATIONS: Limited sample size, no direct comparison with double-balloon endoscopy. CONCLUSIONS: Single-balloon-assisted colonoscopy seems a safe and effective method for completing colonoscopy in patients with previously failed or difficult colonoscopy. The outcomes are similar compared with previous studies with DBE colonoscopy in this patient group.

Long-term response rates to infliximab therapy for Crohn's disease in an outpatient cohort.

BACKGROUND: Infliximab's efficacy in the induction and maintenance of remission in luminal Crohn's disease has been confirmed by randomized, controlled trials. Less clearly described are long-term outcomes in the clinical practice setting since the establishment of regularly scheduled, every eight-week maintenance infliximab infusions. Existing reports describing clinical practice outcomes are limited by short durations of follow-up or by the use of episodic dosing, or focus on safety data rather than clinical outcomes. OBJECTIVE: To examine induction and maintenance responses to infliximab in an outpatient inflammatory bowel disease clinic. METHODS: A retrospective chart review was performed. Clinical outcomes were infliximab induction and maintenance responses, defined as the ability to stop and remain off corticosteroids while not requiring additional therapy for active disease. RESULTS: One hundred thirty-three patients were identified with records sufficiently detailed to be analyzed. Of these, 117 patients (88%) demonstrated a clinical response to induction; 104 of 117 (89%) were on concomitant immunosuppressive therapy; 80 of 104 on azathioprine/6-mercaptopurine (77%); and 24 of 104 on methotrexate (23%). The mean duration of clinical response was 94 weeks (95% CI 78.8 to 109.2). The proportion of patients who maintained response at 30 weeks was 83.2%, at 54 weeks was 63.6% and at 108 weeks was 44.9%. Adverse events occurred for 15 of 117 patients (12.8%), consisting of nine infusion reactions, four serum sickness-like reactions, one rash and one infection. CONCLUSION: Patients treated with infliximab therapy for luminal Crohn's disease in our outpatient clinic achieved excellent induction and maintenance of response rates, confirming the real-life efficacy of maintenance infliximab established in clinical trials.

Clinical characteristics may distinguish patients with esophageal adenocarcinoma arising from long- versus short-segment Barrett's esophagus.

BACKGROUND AND AIMS: Patients with long-segment Barrett's esophagus (LSBE; ≧3 cm) have higher risk of developing esophageal adenocarcinoma (EAC) than those with short-segment Barrett's esophagus (SSBE; <3 cm). However, it is unclear whether patients developing EAC from LSBE or SSBE differ significantly according to baseline clinical characteristics. METHODS: We conducted a retrospective analysis of a prospectively maintained database comprising consecutive patients with early EAC treated by endoscopic mucosal resection at a single, tertiary-referral center. Information regarding baseline clinical characteristics were determined. Univariate and multivariate logistic regression were performed to identify factors that differed significantly between patients with EAC arising from SSBE and LSBE. RESULTS: A total of 145 LSBE EAC and 179 SSBE EAC cases were identified. The LSBE EAC patients had a stronger association with having a hiatal hernia compared to the SSBE EAC patients. In contrast, inverse associations were observed in LSBE EAC patients with statin use and smoking pack-years relative to SSBE EAC patients. CONCLUSIONS: Patients who developed EAC on a background of LSBE were more likely to have a hiatus hernia compared to patients with SSBE EAC, who were more likely to have higher smoking pack-years and higher rates of statin use.

The measurement and clinical significance of intestinal permeability.

This article discusses the concept of intestinal permeability and the barrier function of the gut, elaborates on tight junction structure and the dynamic nature of its composition, outlines the methods for evaluating intestinal permeability, and explores abnormal intestinal permeability in clinical disease, emphasizing its possible role in the pathogenesis of autoimmune conditions. Evidence is provided from several representative diseases for a proposed model of abnormal intestinal permeability in autoimmune disease, including a description of a molecular pathway involving a signaling protein called zonulin, which appears to regulate intestinal permeability. Finally, we speculate on mechanisms that may be responsible for increasing intestinal permeability and consider clinical implications.

Efficacy of single-incision needle-knife biopsy for sampling subepithelial lesions.

Background and study aims Single-incision needle-knife (SINK) biopsy is a diagnostic method for acquiring tissue samples for subepithelial lesions (SELs). A single linear incision is made in the overlying mucosa and tissue samples are obtained by passing conventional biopsy forceps through the opening and deep into the lesion. The aim of this study was to describe the efficacy and safety of this technique. Patients and methods Consecutive patients who underwent SINK biopsy for an upper gastrointestinal SEL between October 2013 and September 2015 were retrospectively reviewed. Results Forty-nine patients underwent 50 SINK biopsies. Sufficient sampling for a definite pathologic diagnosis was obtained in 42 (86 %) cases, with 91 % (40/44) having sufficient sample to perform immunohistochemistry when deemed clinically relevant. Of the 26 patients with prior non-diagnostic biopsies or FNA, a specific diagnosis was obtained in 85 % (22/26). There were no significant adverse events. Conclusions SINK biopsy is a safe and feasible strategy for obtaining a definitive tissue diagnosis with immunohistochemistry for SELs.