Necrosectomy For Walled-off Pancreatic Necrosis Research Articles

Hemostatic matrix for treating intracollection bleeding after endoscopic ultrasound-guided drainage and endoscopic necrosectomy of walled-off pancreatic necrosis in a patient with cirrhosis.

A 45-year-old man with alcoholic liver cirrhosis was referred to our institute for treatment of infected walled-off pancreatic necrosis (WOPN) 6 months after an episode of acute pancreatitis. Computed tomography confirmed cirrhotic liver disease with collateral vessels and a pancreatic fluid collection at the body-tail (9 × 3 cm). Laboratory tests showed low platelets (55 000/mm3) and international normalized ratio of 1.5. Endoscopic ultrasound (EUS) evaluation showed perigastric collateral circulation and a WOPN with necrotic material accounting for 90 % of the total volume ([Fig. 1]).

Percutaneous Chemical and Mechanical Necrosectomy for Walled-Off Pancreatic Necrosis

PurposeTo test the hypothesis that percutaneous combined chemical and mechanical necrosectomy using a Malecot anchor drain and an Arrow-Trerotola percutaneous thrombolytic device (PTD) in patients with walled-off pancreatic necrosis (WOPN) is feasible, safe, and effective compared with a control group undergoing mechanical necrosectomy alone. Materials and MethodsIn a retrospective analysis, patients with WOPN not amenable to endoscopic-guided cystogastrostomy placement were studied as case and control groups. The patients in the case group underwent percutaneous combined chemical (hydrogen peroxide 3%) and mechanical necrosectomy using a Malecot anchor drain and/or Arrow-Trerotola PTD from December 2020 to April 2022. The controls underwent mechanical necrosectomy alone without chemical necrosectomy. Clinical success was defined as complete resolution of the cavity on follow-up noncontrast computed tomography scans with subsequent drain removal. ResultsThirteen patients in the case group and 11 patients in the control group underwent percutaneous drain placement followed by percutaneous combined chemical and mechanical necrosectomy (case group) or mechanical necrosectomy only (control group) for WOPN. Drain placement and necrosectomy were technically successful in all patients studied. One patient in the case group developed postprocedural sepsis because of communication between the cavity and the splenic vein. Another patient in the case group developed bleeding from a branch of the pancreaticoduodenal artery on postnecrosectomy day 9, which was successfully embolized by interventional radiology. No pancreaticocutaneous fistula was reported at the 3-month follow-up. The clinical success rates in the case and control groups were 100% and 38.4%, respectively (P = .003). ConclusionsPercutaneous combined chemical and mechanical necrosectomy is a feasible, safe, and effective treatment of WOPN.

S1093 Assessment of Physical and Mental Health Before and After Protocolized Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis in a Prospective Multi-Center Trial

Introduction: A regulatory FDA IDE prospective multi-center clinical trial (G170261-NCT03525808) was performed to evaluate rigorous protocolized management of walled off necrosis (WON) ≥ 6 cm in size with > 30% necrotic material using endoscopic ultrasound (EUS) guided lumen apposing metal stent (LAMS) placement with/without endoscopic necrosectomy. Few studies have examined changes in health related quality of life (HRQOL) before and after endoscopic management for WON. The SF-12 is a validated measure of HRQOL containing 12 items which yield a Mental Components Score (MCS) and a Physical Components Score (PCS). Higher scores correspond to a greater perceived quality of life. Methods: The pre-specified target sample of 40 consecutive eligible patients was enrolled by multiple centers from September 2018 to March 2020. Patients with radiographic WON resolution (as demonstrated by size ≤ 3 cm on CT or MRI) and/or 60 days LAMS indwell time had stent removal followed by an end of study visit 6 months later. SF-12 quality of life questionnaires were completed by patients at baseline, stent removal and at the end of study visit. Results: Mean SF-12 Physical Components Score (PCS) was 27.5±21.1 at baseline, 54.4±19.5 at the time of LAMS removal, and 77.9±22.3 at end of study. Mean SF-12 Mental Components Score (MCS) was 44.9±20.1 at baseline, 64.7±16.5 at the time of LAMS removal, and 79.0±17.2 at end of study. The mean improvement in PCS score from baseline to LAMS removal was 26.0±24.8 (p< 0.0001), with the mean improvement in score from baseline to end of the study being 49.1±29.6 (p< 0.0001). The mean improvement in MCS was 19.6±20.1 from baseline to LAMS removal (p< 0.0001) and 32.0±22.3 from baseline to the end of study (p< 0.0001). The mean improvement from the time of stent removal to the end of study was 25.2±18.0 (PCS, p< 0.0001) and 15.5±18.5 (MCS, p=0.0002) (Figure). Conclusion: These data suggest that patients undergoing protocolized endoscopic necrosectomy for walled-off pancreatic necrosis experience significant improvement in both physical and mental HRQOL. Improvement in the physical score domain appeared to be greater than for the mental score domain. HRQOL indicators continued to improve over a mean follow-up of 180 days.Figure 1.: SF-12 Physical and Mental Components Score.

Tunnel creation method in endoscopic necrosectomy for walled-off pancreatic necrosis.

Tunnel creation method in endoscopic necrosectomy for walled-off pancreatic necrosis.

S99 Hydrogen Peroxide-Assisted Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis: A Systematic Review and Meta-Analysis

Introduction: Endoscopic necrosectomy (EN) is the preferred approach for drainage of walled-off pancreatic necrosis (WOPN) commonly performed with the aid of endoscopic ultrasound (EUS) guided. Hydrogen peroxide (H2O2) has been reported to be a good adjunctive therapy for Direct Endoscopic Necrosectomy (DEN). We performed a systematic review and meta-analysis to evaluate effectiveness and safety of H2O2 assisted EN for WOPN. Methods: A comprehensive search of multiple databases (through December 2020) was performed to identify studies that reported outcomes of H2O2 assisted EN for WOPN. Outcomes assessed included clinical success, technical success, and adverse events. Results: A total of 454 patients with mean age (47.3 ± 7.9 years) and WOPN size (12.4 ± 3.1 cm) were included from 15 studies. The mean number of procedures performed were 3.0 ± 0.9 and majority of patients underwent trans-gastric approach (n=288). The rates of technical success, clinical success and adverse events was 97.3 (95% confidence interval [CI]: 94.8 – 98.6, I2 =0), 89.8% (95% CI: 86.3 – 92.5, I2 =0) and 17.9% (95% CI: 12.6 – 24.7, I2 =38), respectively. The most common adverse event was bleeding with rate of 7.1% followed by stent migration (5.3%). On meta-regression, lesion size, patient age, metal stent, number of necrosectomies and transgastric access was not significant predictor for technical success, clinical success, adverse events or bleeding. Conclusion: To the best of our knowledge, this is the first systemic review and meta-analysis to evaluate effectiveness and safety of H2O2 assisted EN for WOPN. EUS-guided drainage followed by necrosectomy of WOPN has become preferred procedure either independently or as a part of step-up approach. H2O2 assisted EN is highly effective and safe for drainage of WOPN. Its use should be encouraged, and future randomized controlled studies are needed to study the predictors of success.Figure 1.: PRISMA Flow diagram showing search strategy for meta-analysis.

Hydrogen peroxide assisted endoscopic necrosectomy for walled-off pancreatic necrosis: A systematic review and meta-analysis

Background and aimsEndoscopic necrosectomy (EN) is the preferred approach for management of symptomatic or infected walled-off pancreatic necrosis (WOPN). Hydrogen peroxide (H2O2) has been reported to be a good adjunctive therapy for EN. We performed a systematic review and meta-analysis to evaluate effectiveness and safety of H2O2 assisted EN for WOPN. MethodsA comprehensive search of multiple databases (through December 2020) was performed to identify studies that reported outcomes of H2O2 assisted EN for WOPN. Outcomes assessed included clinical success, technical success, and adverse events. ResultsA total of 454 patients with mean age (47.3 ± 7.9 years) and WOPN size (12.4 ± 3.1 cm) were included from 15 studies. The median H2O2 concentration was 3% (range 0.1–3%), with dilution and volume ranging from 1:1 to 10:1 and 20 ml to 1 L, respectively. The rates of technical success, clinical success and adverse events was 97.3% (95% confidence interval [CI]: 94.8–98.6, I2 = 0), 89.8% (95% CI: 86.3–92.5, I2 = 0) and 17.9% (95% CI: 12.6–24.7, I2 = 38), respectively. The most common adverse event was bleeding (7.1%) followed by stent migration (5.3%). On meta-regression, WOPN size, patient age, use of metal stent, number of necrosectomies and transgastric access were not significant predictor for technical success, clinical success or adverse events. ConclusionH2O2 assisted EN is effective and safe for management of WOPN. Its use may be encouraged, and future randomized controlled studies are needed to study the optimal technique, concentration and best predictors of success.

Transfer of a lumen-apposing metal stent to a different fistula for endoscopic necrosectomy of walled-off pancreatic necrosis.

Transfer of a lumen-apposing metal stent to a different fistula for endoscopic necrosectomy of walled-off pancreatic necrosis.

Laparoscopic transgastric necrosectomy for walled-off pancreatic necrosis

Laparoscopic transgastric necrosectomy for walled-off pancreatic necrosis

Comparative Study of Conventional and Transgastric Necrosectomy for WideExtended Walled-of Pancreatic Necrosis

Purpose: Even though endoscopic necrosectomy for walled-off pancreatic necrosis is safe and effective, open surgery has an important role in cases with extended necrosis when the non-surgical approaches are not feasible. Authors compare their results of conventional and transgastric open necrosectomy. Methods: A total of 29 patients were treated with extended walled-off pancreatic necrosis. Conventional open necrosectomy with closed bursal lavage was performed in group A (18 patients) and transgastric necrosectomy was performed in group B (11 patients). There were no significant differences between the two groups related to sex, age, etiology of pancreatitis, size of WOPN and time elapsed from the onset of disease and surgery. Results: For all complications, the difference was significant between both groups (p=0.003). In group A, 13 reoperations were performed in 9 patients and none were required in group B. The difference between both groups was significant (p=0.01). The length of hospital stay was 23 ± 14.16 days in group A and 12 ± 2.2 days in group B. The difference was significant (p=0.001). The mortality in group A was higher than in group B (p=0.143), but it was not significant. The mean mortality rate was 13.8% in 29 patients. Conclusion: In patients with extended walled-off pancreatic necrosis, the open transgastric necrosectomy has better results than conventional necrosectomy.

2 Hydrogen Peroxide-Assisted Endoscopic Necrosectomy vs. Standard Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis: A Multi-Center Retrospective Comparative Study

INTRODUCTION: Endoscopic necrosectomy has emerged as the preferred treatment modality for walled off pancreatic necrosis (WON). Standard endoscopic necrosectomy can be tedious and time consuming, employs sharp instruments in vascular cavities, and does not provide for microdebridement. Hydrogen peroxide (H2O2) lavage has been reported in small series; however, there have been no comparative studies on its safety and efficacy in the management of WON. METHODS: We performed a retrospective chart review of all cases undergoing endoscopic transmural management of WON at 9 major medical centers in the US from November 2011 to August 2018. Cystogastrostomies were performed using lumen apposing metal stents (LAMS). Patients who underwent cystogastrostomy without necrosectomy were excluded. Clinical success was defined as resolution of the WON by imaging within 6 months, without requiring non-endoscopic drainage procedures or surgery. RESULTS: A total of 296 patients underwent cystgastrostomy and 206 patients underwent one or more necrosectomies. Clinical success was achieved in 171/192 (89.1%) of those with follow-up data at 6 months. In terms of patients, 122 (59.2%) patients had at least one H2O2 necrosectomy (H2O2 group), and 84 (40.8%) patients had standard endoscopic necrosectomy. Clinical success was higher in the H2O2 group (n = 107 (95.5%) vs 63 (79.7%), P &lt; 0.001). On multivariate logistic regression, the use of hydrogen peroxide (OR 17.4, 95% CI: 2.9–103, P = 0.002) was associated with higher clinical success rates (Table 2). During a mean follow up of 278 days, 29 complications occurred: bleeding (n = 18), perforation (n = 5), respiratory complication (n = 3), and sepsis (n = 3). One death was presumed to be procedure related (splenic pseudoaneurysm rupture day 8; standard necrosectomy group). A total of 394 necrosectomies were performed. Comparing necrosectomy procedures with and without H2O2 (n = 209 vs 185), there was no difference in procedure time (72.5 ± 39.6 vs 72 ± 44.2, P = 0.936), post-procedural bleeding (8 vs 10, P = 0.45), perforation (3 vs 2, P = 1), infection (1 vs 2, P = 0.6) or overall complication rate (n = 15 (7.1%) vs 14 (7.6%), P = 1) (Table 3). CONCLUSION: In this multicenter retrospective cohort study, H2O2 necrosectomy appeared to be safe and effective with a higher clinical success rate and equivalent rates of bleeding, perforation, death, and overall complications relative to standard necrosectomy.

Transcutaneous Endoscopic Necrosectomy for Walled-off Pancreatic Necrosis in the Paracolic Gutter.

Walled-off pancreatic necrosis (WON) is a sequelae of acute pancreatitis that requires debridement, once infected. Recently, endoscopic necrosectomy has become the mainstay for management. However, peripancreatic collections that extend to the paracolic gutter or lesser sac, are more challenging to treat endoscopically. We report an endoscopic method for management of necrotic collections that extend into the paracolic gutter. Consecutive patients, with symptomatic WON extending into the retroperitoneum, were included in a prospective registry. Each patient underwent transcutaneous endoscopic necrosectomy (TEN) through a fully covered self-expanding esophageal metal stent. After resolution of the collection, the external stent was removed, and the cutaneous fistula was allowed to close by secondary intention. Clinical success was defined as resolution of the WON, and successful removal of all percutaneous drains. Patient demographics, procedural/periprocedural adverse events, and follow-up data, were collected. Nine patients underwent direct TEN. Patients initially underwent CT-guided percutaneous drainage, with an average of 31 days between initial drainage and endoscopic necrosectomy. All patients had a technically successful placement of a fully covered esophageal metal stent through the cutaneous fistula. After a median of 3 endoscopic debridement sessions, 8 of 9 (89%) patients had successful removal of all percutaneous drains, and resolution of necrotic collections. One patient died of multisystem organ failure from severe acute pancreatitis. TEN for infected WON is a safe and efficacious technique for patients with endoscopically inaccessible collections.

Endoscopy International Open – recently published

Comment on: Radiofrequency ablation (RFA) vs. argon plasma coagulation (APC) for the management of gastric antral vascular ectasia (GAVE) in patients with and without cirrhosis: results from a retrospective analysis of a large cohort of patients treated at a single centerEndosc Int Open 2018; 06(03): E266-E270DOI: 10.1055/s-0043-123187 Comment on: Endoscopic necrosectomy of walled-off pancreatic necrosis by large-bore percutaneus metal stent: a new opportunity?Endosc Int Open 2018; 06(03): E274-E278DOI: 10.1055/s-0043-125313 Comment on: Effective and less invasive diagnostic strategy for gastrointestinal GVHDEndosc Int Open 2018; 06(03): E281-E291DOI: 10.1055/s-0043-122226

688 Effect of Scheduled Versus ‘Step-Up’ Necrosectomy for Walled-Off Pancreatic Necrosis on Hospital Admissions and Necrosis Resolution

688 Effect of Scheduled Versus ‘Step-Up’ Necrosectomy for Walled-Off Pancreatic Necrosis on Hospital Admissions and Necrosis Resolution

Fungal Infections in Patients With Walled-off Pancreatic Necrosis.

This study aimed to evaluate the influence of fungal infection and antifungal treatment on outcome in patients with walled-off pancreatic necrosis (WON). A retrospective description of fungal infections in a cohort of consecutive patients undergoing endoscopic, transmural drainage and necrosectomy for WON, treated in a tertiary referral center was reviewed. Between 2005 and 2013, fungal infection in WON was documented in 57 (46%) of 123 patients. The most common isolates at first positive culture were Candida albicans (55%) and Candida glabrata (20%). Thirty-nine (70%) patients were treated with antifungals after the first fungal finding. There was no significant difference in mortality (21% vs 13%, P = 0.517) or organ failure (34% vs 33%, P = 0.903) between the group treated with adequate antifungals after the first fungal finding compared to the group not treated or treated inadequately.The in-hospital mortality was 18% (10 patients). Concomitant fungemia was found in 6 patients, of which 3 died, as opposed to 7 with fungi in the necrosis only (50% vs 14%, P = 0.027). This study demonstrates a high incidence and associated high in-hospital mortality of fungal infection in WON, thus emphasizing the importance of fungal infections in WON.

Endoscopic Ultrasound Guided Necrosectomy of Walled-Off Pancreatic Necrosis Using a Lumen-Apposing Fully Covered Metal Stent and Hydrogen Peroxide: A Single Center Experience

Introduction: A natural sequela of pancreatic necrosis is the development of cystic cavities containing necrotic pancreatic tissue and fluid known as walled-off pancreatic necrosis(WOPN). Historically, surgical necrosectomy has been the mainstay of treatment; however, advances in therapeutic endoscopy have led to increased utilization of less invasive treatment modalities. We studied the use of lumen-apposing fully covered metal stents(LAMS) and hydrogen peroxide(H2O2) lavage in the management of WOPN at our academic medical center. Methods: 10 patients underwent Endoscopic Ultrasound(EUS) guided necrosectomy using LAMS and H2O2 lavage for the management of WOPN from 4/2015-4/2016. EUS was performed using a linear echoendoscope at a frequency of 7.5 MHz with CO2 gas used for insufflation. The cyst cavity was punctured using a 19-gauge needle. After stylet withdrawal in patients 1-6, a 0.035” diameter x 480cm long, straight tip guidewire was used to facilitate the passage of a 10 Fr cystotome into the necrotic cavity. Using EUS and endoscopic guidance, a 15mm x 10mm LAMS was then placed in the necroma, with placement confirmed on fluoroscopy. In patients 7-10, an electrocautery-enhanced LAMS measuring 15mm x 10mm was placed directly into the cyst over the guidewire. In all cases, a balloon was then advanced over the guidewire, through the stent, and into the necroma, followed by inflation to 15mm. The echoendoscope was then withdrawn and a forward-viewing endoscope was utilized to perform direct endoscopic necrosectomy(DEN). Upon completion of DEN, the necroma was lavaged with 100cc of 0.3% H2O2, which was not suctioned out of the cavity. PPIs were held 30 days post initial intervention. Results: The patient cohort had a median age of 52.5±15.5 years and was 60% male. The median size of the WOPN was 10±4.4cm. The technical success rate was 100%, with all patients undergoing successful LAMS placement. Clinical success was achieved in 80% of patients and resolution of WOPN was confirmed via cross-sectional imaging in these patients. Patients had a median of 2 DENs and a median follow-up of 91 days. One patient required escalation to surgical necrosectomy and one patient died 13 days post stent placement due to multisystem organ failure, not related to the procedure. Conclusion: The use of LAMS and H2O2 appears to offer patients a safe, effective and minimally-invasive alternative to surgical necrosectomy, which is associated with significant morbidity and mortality.Table 1Figure 1Figure 2

Endoscopic necrosectomy of walled-off pancreatic necrosis using a lumen-apposing metal stent and irrigation technique.

Endoscopic management of walled-off pancreatic necrosis (WOPN) is an area of great interest with many still unanswered questions, including the role of mechanical necrosectomy versus irrigation. The aim of this study was to evaluate a new method of endoscopic transmural necrosectomy. Patients with WOPN after necrotizing pancreatitis, who underwent endoscopic transmural necrosectomy using a lumen-apposing metal stent with vigorous irrigation sessions, were prospectively recruited between September 2011 and August 2014. Initial endoscopic session was performed by EUS-guided drainage and lavage sessions by flushing saline through the stent. Technical and clinical success rates, number of repeat interventions, and adverse events were analyzed. Twelve patients with 13 WOPN collections (median size 12.4±2.94cm) underwent endoscopic treatment. Clinical success was achieved in 100% of cases after a median of three sessions per patient (range 2-8). The median length of hospitalization was 15.9days. Median procedure time of the access session was 31±10.16min. No adverse events (AE) were described during the procedures or 24h after. There were four AE (two infections and two bleedings) between sessions, but only two were severe (16.6%). There was no need for surgery, and no mortalities occurred. Mean time to stent retrieval was 9±3.4weeks. Mean follow-up was 13months with only one recurrence at 12months after stent removal. This new variant of irrigation endoscopic transmural necrosectomy without mechanical debridement helps to simplify the technique, is feasible, and has excellent outcomes in WOPN treatment.

Endoscopic ultrasound-guided drainage and necrosectomy of walled-off pancreatic necrosis using a metal stent with an electrocautery-enhanced delivery system and hydrogen peroxide.

Direct endoscopic necrosectomy of walled-off pancreatic necrosis (WOPN) has recently been reported to have comparable success rates to surgery, but with lower morbidity and mortality [1] [2]. The procedure is, however, time consuming and requires multiple device exchanges [3], which may increase the risk of complications.

Safety and Effectiveness of Using Hydrogen Peroxide in Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis: A Comparative Evaluation of Outcomes

Safety and Effectiveness of Using Hydrogen Peroxide in Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis: A Comparative Evaluation of Outcomes

Hydrogen Peroxide-Assisted Endoscopic Necrosectomy for Walled-Off Pancreatic Necrosis: A Dual Center Pilot Experience

Pancreatic necrosis (PNec) is a serious local complication occurring in 10–15 % of patients with acute pancreatitis (AP). Necrotizing pancreatitis can organize into necrotic collections, termed walled-off necrosis (WON) [1, 2]. Symptomatic WON has traditionally been treated operatively [3]. In several recent trials, successful resolution of WON was achieved using endoscopic therapy, termed direct endoscopic necrosectomy (DEN) [4, 5]. A challenge to DEN is removal of all necrotic material from within the collection [6, 7]. Hydrogen peroxide (H2O2) is acknowledged as an effective means to achieve mechanical debridement of wounds [8–11]. In this case series, we describe a dual center experience with the use of H2O2 to facilitate removal of necrotic debris in patients undergoing DEN as the preliminary measure for management of WON.

Endoscopic transmural necrosectomy for walled-off pancreatic necrosis: a systematic review and meta-analysis.

Endoscopic transmural necrosectomy (ETN) is emerging as a viable treatment option for walled-off pancreatic necrosis. This NOTES-type procedure is significantly less invasive than an extensive surgical debridement; however, published data regarding the success of ETN in treating pancreatic necrosis have varied. To evaluate the published medical literature to determine the success of treating walled-off pancreatic necrosis with ETN. Studies using ETN as a primary mode of therapy to treat organized pancreatic necrosis were selected. Success was defined as resolution of the necrotic cavity proven by radiology. Articles were searched in Medline, PubMed, Ovid journals, CINAH, old Medline, Medline nonindexed citations and the Cochrane controlled trials registry. The summary estimates were expressed as pooled proportions. First, the individual study proportions were transformed into a quantity using Freeman-Tukey variant of the arcsine square root transformed proportion. The pooled proportion was calculated as the back-transform of the weighted mean of the transformed proportions, using inverse arcsine variance weights for the fixed-effects model and DerSimonian-Laird weights for the random-effects model. Publication bias was calculated using the Begg-Mazumdar and Harbord bias estimators. The initial search identified 920 reference articles, of which 129 relevant articles were selected and reviewed. Data were extracted from eight studies (n=233) that met the inclusion criteria. Organization of pancreatic necrosis was determined by computed tomography scan in all of the studies. The mean time of ETN after onset of acute pancreatitis⁄abdominal pain was seven weeks. The weighted mean size of the necrotic cavity was 12.87 cm (95% CI 10.54 cm to 15.20 cm). The weighted mean number of endoscopic procedures needed to resolve the necrotic cavity was 4.09 (95% CI 2.31 to 5.87). Pooled proportion of successful resolution of pancreatic necrosis using ETN was 81.84% (95% CI 76.73% to 86.44%). The pooled proportion of recurrence in the form of necrotic cavity or pseudocyst after ETN was 10.88% (95% CI 7.27% to 15.11%). Complications were noted in 21.33% (95% CI 16.40% to 26.72%) of patients and included bleeding, sepsis and perforation. The weighted mean number of days in hospital after ETN was 32.85 days (95% CI 10.50 to 55.20 days). For pancreatic necrosis that did not resolve, surgery had to be performed in 12.98% (95% CI 9.05% to 17.51%) of patients. The fixed-effect model was used to report all of the pooled proportions. Estimates calculated using fixed- and random-effects models were similar. Test of heterogeneity yielded P>0.10, indicating that the studies could be combined. The publication bias calculated using Begg-Mazumdar bias indicator yielded a Kendall's tau b value of -0.07 (P=0.72) and the same using Harbord bias indicator gave a value of 0.33 (95% CI -1.35 to 2.01; P=0.60). Both of these indicators show that there was no publication bias. The present meta-analysis showed that ETN is safe and effective at treating patients with symptomatic walled-off necrosis. ETN offers the advantage of minimally invasive endoscopic treatment without transabdominal surgery; however, better techniques and equipment are still needed to improve procedural efficiency. Decisions to perform ETN should be made by advanced endoscopists in collaboration with a multidisciplinary team with the facilities and personnel to manage these complex patients.