Non-superiority of lumen-apposing metal stents over plastic stents for drainage of walled-off necrosis in a randomised trial

Endoscopic Drainage of Pancreatic Fluid Collections

Pancreatic fluid collections (PFCs) are commonly encountered complications of acute and chronic pancreatitis. With the advancement of endoscopic ultrasound (EUS) techniques and devices, EUS-directed transmural drainage of symptomatic or infected PFCs has become the standard of care. Traditionally, plastic stents have been used for drainage, although lumen-apposing metal stents (LAMSs) are now favored by most endoscopists due to ease of use and reduced procedure time. While safety has been repeatedly demonstrated, follow-up care for these patients is critical as delayed adverse events of indwelling drains are known to occur.

Controversies in endoscopic ultrasonography-guided management of walled-off necrosis

Walled-off necrosis (WON) develops as local complications after acute necrotizing pancreatitis. Although less invasive interventions such as endoscopic ultrasonography (EUS)-guided drainage and endoscopic necrosectomy are selected over surgical interventions, delayed and step-up interventions are still preferred to avoid procedure-related adverse events. However, there is a controversy about the appropriate timing of drainage and subsequent necrosectomy. The advent of large-caliber lumen-apposing metal stents has also brought about potential advantages of proactive interventions, which still needs investigation in future trials. When step-up interventions of necrosectomy and additional drainage are necessary, a structured or protocoled approach for WON has been reported to improve safety and effectiveness of endoscopic and/or percutaneous treatment, but has not been standardized yet. Finally, long-term outcomes such as recurrence of WON, pancreatic endocrine, and exocrine function are increasingly investigated in association with disconnected pancreatic duct syndrome. In this review we discuss current evidence and controversy on EUS-guided management of WON.

Endoscopic ultrasound-guided pancreatic fluid collection drainage: Where are we?

Pancreatic fluid collections (PFCs) result from injury to the pancreas from acute or chronic pancreatitis, surgery, or trauma. Management of these collections has evolved over the last 2 decades. The choice of interventions includes percutaneous, endoscopic, minimally invasive surgery, or a combined approach. Endoscopic drainage is the drainage of PFCs by creating an artificial communication between the collection and gastrointestinal lumen that is maintained by placing a stent across the fistulous tract. In this editorial, we endeavored to update the current status of endoscopic ultrasound-guided drainage of PFCs.

Impact of long-term transmural plastic stents on recurrence after endoscopic treatment of walled-off pancreatic necrosis

BACKGROUND

Endoscopic transmural drainage (ETD) using double-pigtail stents (DPSs) is a well-established treatment for walled-off pancreatic necrosis (WON). This study aimed to compare outcomes in patients undergoing ETD with DPSs left indwelling versus those where stents were removed or migrated.

METHODS

This retrospective multicenter cohort study included patients with WON who underwent ETD using DPSs between July 2001 and December 2019. The primary outcome was recurrence of a pancreatic fluid collection (PFC). Secondary outcomes were long-term complications and recurrence-associated factors. Competing risk regression analysis considered DPS removal or migration as time-varying covariates.

RESULTS

Among 320 patients (median age 58; 36% women), DPSs were removed in 153 (47.8%), migrated spontaneously in 27 (8.4%), and remained indwelling in 140 (43.8%). PFC recurrence was observed in 57 patients (17.8%): after removal (n = 39; 25.5%); after migration (n = 4; 14.8%); in patients with indwelling DPSs (n = 14; 10.0%). In 25 patients (7.8%), drainage of recurrent PFC was indicated. Risk factors for recurrence were DPS removal or migration (hazard ratio [HR] 3.45, 95%CI 1.37-8.70) and presence of a disconnected pancreatic duct (HR 5.08, 95%CI 1.84-14.0).

CONCLUSIONS

Among patients who undergo ETD of WON, leaving DPSs in situ seems to lower the risk of recurrent fluid collections, without any long-term DPS-related complications. These results suggest that DPSs should not be routinely removed and can be safely left indwelling indefinitely.

Equivalent efficacy and safety of plastic stents and lumen-apposing metal stents in the treatment of peripancreatic fluid collections: a prospective cohort study

Background

Endoscopic ultrasound (EUS)-guided transmural drainage using double pigtail plastic stents (DPPS) has been routine for the treatment of peripancreatic fluid collections (PFC). Lumen-apposing metal stents (LAMS) have since their introduction been the preferred choice; however, their superiority has not been proven. The aim of this study was to compare the efficacy and safety of DPPS and LAMS.

Methods

This was a single-center, prospective study that included consecutive patients undergoing EUS-guided drainage between January 2010 and December 2020. The primary endpoints were technical success, clinical success and adverse event rate, while the secondary endpoints included symptomatic relief, length of hospital stay, and need for adjunct drainage. A subgroup analysis of walled-off necrosis (WON) was performed.

Results

A total of 89 patients (median age 56 years) underwent EUS-guided transmural drainage (DPPS: n=53; LAMS: n=36) because of a pseudocyst (n=37) or a WON (n=52). Both DPPS and LAMS had a 100% technical success rate and a comparable adverse event rate (4% vs. 6%, P=0.24). An equivalent efficacy was recorded for the drainage of PFC comparing DPPS and LAMS, and no significant statistical difference was recorded in clinical success (DPPS 60% vs. LAMS 61%, P=0.94) or the need for reintervention (DPPS 11% vs. LAMS 13%, P=0.72).

Conclusions

In this large, prospective study of EUS-guided drainage of peripancreatic fluid collections, LAMS and DPPS showed equivalent safety, technical success, clinical success and hospital stay. Both techniques were associated with a comparable need for complementary necrosectomy.

Role of advanced endoscopy in the management of inflammatory digestive diseases (pancreas and biliary tract)

The progress of endoscopic diagnosis and treatment for inflammatory diseases of the biliary tract and pancreas have been remarkable. Endoscopic ultrasonography (EUS) and EUS-elastography are used for the diagnosis of early chronic pancreatitis and evaluation of endocrine and exocrine function in chronic pancreatitis. Notably, extracorporeal shock wave lithotripsy and electrohydraulic shock wave lithotripsy have improved the endoscopic stone removal rate in patients for whom pancreatic stone removal is difficult. Studies have reported the use of self-expanding metal stents for stent placement for pancreatic duct stenosis and EUS-guided pancreatic drainage for refractory pancreatic duct strictures. Furthermore, EUS-guided drainage using a double-pigtailed plastic stent has been performed for the management of symptomatic pancreatic fluid collection after acute pancreatitis. Recently, lumen-apposing metal stents have led to advances in the treatment of walled-off necrosis after acute pancreatitis. EUS-guided biliary drainage is an alternative to refractory endoscopic biliary drainage and percutaneous transhepatic biliary drainage for the treatment of acute cholangitis. The placement of an inside stent followed by switching to uncovered self-expanding metal stents in difficult-to-treat cases has been proposed for acute cholangitis by malignant biliary obstruction. Endoscopic transpapillary gallbladder drainage is an alternative to percutaneous transhepatic gallbladder drainage for severe and some cases of moderate acute cholecystitis. EUS-guided gallbladder drainage has been reported as an alternative to percutaneous transhepatic gallbladder drainage and endoscopic transpapillary gallbladder drainage. However, it is important to understand the advantages and disadvantages of each drainage method and select the optimal drainage method for each case.

Efficacy and safety of long-term indwelling plastic stents after resolution of pancreatic fluid collections with endoscopic transmural drainage: a systematic review and meta-analysis

BACKGROUND

Pancreatic fluid collections (PFCs) may recur after resolution with endoscopic transmural drainage (ETD) and standard stent removal (SSR). Herein, we compared the efficacy and safety of leaving long-term indwelling plastic stents (LTIS) vs. standard stent removal after PFC resolution with ETD.

METHODS

We performed a systematic review of MEDLINE, EMBASE, CINAHL, Scopus, and Cochrane databases from inception to September 2022. Full-text articles comparing long-term (> 6 months) outcomes of LTIS and SSR were eligible, as well as single-arm studies with ≥ 10 patients with LTIS. Two independent reviewers selected studies, extracted data, and assessed the risk of bias using the Newcastle-Ottawa Scale. Measured outcomes included the following: (A) PFC recurrence; (B) interventions for PFC recurrence; (C) technical success; and (D) adverse events (AEs). Meta-analysis was carried out using random-effects models.

RESULTS

We included 16 studies, encompassing 1285 patients. Compared to SSR after PFC resolution with ETD, LTIS was associated with significantly lower risk of PFC recurrence (3% vs. 23%; OR 0.22 [95%CI 0.09-0.52]; I2 = 45%) and need for interventions (2% vs. 14%; OR 0.35 [95%CI 0.16-0.78]; I2 = 0%). The superiority of LTIS on reducing PFC recurrence was found with walled-off necrosis, with or without disconnected pancreatic duct, and with placement of ≥ 2 LTIS. When using LTIS, the pooled proportion of AEs was 8% (95%CI 4-11%) and technical success was 93% (95%CI 86-99%).

CONCLUSIONS

Our results show that LTIS after PFC resolution with ETD is feasible, safe, and superior to SSR in reducing the risk of PFC recurrence and need for interventions.

Risk factors for adverse outcomes at various phases of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Data from a multi-institutional consortium

OBJECTIVES

No comprehensive study has examined short- and long-term adverse outcomes of endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs) including walled-off necrosis (WON) and pseudocysts.

METHODS

In a multi-institutional cohort of 357 patients receiving EUS-guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type-specific risk factors for procedure-related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders.

RESULTS

Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00-6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61-16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05-6.35), extension to the pelvis (OR 3.63; 95% CI 1.57-8.43), nonuse of a lumen-apposing metal stent (OR 2.88; 95% CI 1.10-7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27-10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10-25.3) and 5.52 (95% CI 1.61-18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11-11.6).

CONCLUSION

The adverse outcomes at various phases of EUS-guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high-risk patients.

Infected pancreatic necrosis-Current trends in management

Acute necrotizing pancreatitis is a common gastrointestinal disease requiring hospitalization and multiple interventions resulting in higher morbidity and mortality. Development of infection in such necrotic tissue is one of the sentinel events in natural history of necrotizing pancreatitis. Infected necrosis develops in around 1/3rd of patients with necrotizing pancreatitis resulting in higher mortality. So, timely diagnosis of infected necrosis using clinical, laboratory and radiological parameters is of utmost importance. Though initial conservative management with antibiotics and organ support system is effective in some patients, a majority of patients still requires drainage of the collection by various modalities. Mode of drainage of infected pancreatic necrosis depends on various factors such as the clinical status of the patient, location and characteristics of collection and availability of the expertise and includes endoscopic, percutaneous and minimally invasive or open surgical approaches. Endoscopic drainage has proved to be a game changer in the management of infected pancreatic necrosis in the last decade with rapid evolution in procedure techniques, development of novel metal stent and dedicated necrosectomy devices for better clinical outcome. Despite widespread adoption of endoscopic transluminal drainage of pancreatic necrosis with excellent clinical outcomes, peripheral collections are still not amenable for endoscopic drainage and in such scenario, the role of percutaneous catheter drainage or minimally invasive surgical necrosectomy cannot be understated. In a nutshell, the management of patients with infected pancreatic necrosis involves a multi-disciplinary team including a gastroenterologist, an intensivist, an interventional radiologist and a surgeon for optimum clinical outcomes.

Long-Term Outcome of Immediate Versus Postponed Intervention in Patients With Infected Necrotizing Pancreatitis (POINTER): Multicenter Randomized Trial

OBJECTIVE

To compare the long-term outcomes of immediate drainage versus the postponed-drainage approach in patients with infected necrotizing pancreatitis.

BACKGROUND

In the randomized POINTER trial, patients assigned to the postponed-drainage approach using antibiotic treatment required fewer interventions, as compared with immediate drainage, and over a third were treated without any intervention.

METHODS

Clinical data of those patients alive after the initial 6-month follow-up were re-evaluated. The primary outcome was a composite of death and major complications.

RESULTS

Out of 104 patients, 88 were re-evaluated with a median follow-up of 51 months. After the initial 6-month follow-up, the primary outcome occurred in 7 of 47 patients (15%) in the immediate-drainage group and 7 of 41 patients (17%) in the postponed-drainage group (RR 0.87, 95% CI 0.33-2.28; P =0.78). Additional drainage procedures were performed in 7 patients (15%) versus 3 patients (7%) (RR 2.03; 95% CI 0.56-7.37; P =0.34). The median number of additional interventions was 0 (IQR 0-0) in both groups ( P =0.028). In the total follow-up, the median number of interventions was higher in the immediate-drainage group than in the postponed-drainage group (4 vs. 1, P =0.001). Eventually, 14 of 15 patients (93%) in the postponed-drainage group who were successfully treated in the initial 6-month follow-up with antibiotics and without any intervention remained without intervention. At the end of follow-up, pancreatic function and quality of life were similar.

CONCLUSIONS

Also, during long-term follow-up, a postponed-drainage approach using antibiotics in patients with infected necrotizing pancreatitis results in fewer interventions as compared with immediate drainage and should therefore be the preferred approach.

TRIAL REGISTRATION

ISRCTN33682933.

International Consensus Recommendations for Safe Use of LAMS for On- and Off-Label Indications Using a Modified Delphi Process

INTRODUCTION

The study aimed to develop international consensus recommendations on the safe use of lumen-apposing metal stents (LAMSs) for on- and off-label indications.

METHODS

Based on the available literature, statements were formulated and grouped into the following categories: general safety measures, peripancreatic fluid collections, endoscopic ultrasound (EUS)-biliary drainage, EUS-gallbladder drainage, EUS-gastroenterostomy, and gastric access temporary for endoscopy. The evidence level of each statement was determined using the Grading of Recommendations Assessment, Development, and Evaluation methodology.International LAMS experts were invited to participate in a modified Delphi process. When no 80% consensus was reached, the statement was modified based on expert feedback. Statements were rejected if no consensus was reached after the third Delphi round.

RESULTS

Fifty-six (93.3%) of 60 formulated statements were accepted, of which 35 (58.3%) in the first round. Consensus was reached on the optimal learning path, preprocedural imaging, the need for airway protection and essential safety measures during the procedure, such as the use of Doppler, and measurement of the distance between the gastrointestinal lumen and the target structure. Specific consensus recommendations were generated for the different LAMS indications, covering, among others, careful patient selection, the preferred size of the LAMS, the need for antibiotics, the preferred anatomic location of the LAMS, the need for coaxial pigtail placement, and the appropriate management of LAMS-related adverse events.

DISCUSSION

Through a modified international Delphi process, we developed general and indication-specific experience- and evidence-based recommendations on the safe use of LAMS.

Lumen-apposing metal stents for the treatment of pancreatic and peripancreatic fluid collections and bleeding risk: a propensity matched study

INTRODUCTION

 Endoscopic ultrasound (EUS)-guided drainage of symptomatic pancreatic fluid collections (PFCs) using the Hot-Axios device has recently been associated with a significant risk of bleeding. This adverse event (AE) seems to occur less frequently with the use of a different device, the Spaxus stent. The aim of the current study was to compare the rates of bleeding between the two stents.

METHODS

 Patients admitted for treatment of PFCs by EUS plus lumen-apposing metal stent in 18 endoscopy referral centers between 10 July 2019 and 28 February 2022 were identified and their outcomes compared using a propensity-matching analysis.

RESULTS

 363 patients were evaluated. After a 1-to-1 propensity score match, 264 patients were selected (132 per group). The technical and clinical success rates were comparable between the two groups. Significantly more bleeding requiring transfusion and/or intervention occurred in the Hot-Axios group than in the Spaxus group (6.8% vs. 1.5%; P = 0.03); stent type was a significant predictor of bleeding in both univariate and multivariate regression analyses (P = 0.03 and 0.04, respectively). Bleeding necessitating arterial embolization did not however differ significantly between the two groups (3.0% vs. 0%; P = 0.12). In addition, the Hot-Axios was associated with a significantly higher rate of overall AEs compared with the Spaxus stent (9.8% vs. 3.0%; P = 0.04).

CONCLUSION

 Our study showed that, in patients with PFCs, bleeding requiring transfusion and/or intervention occurred significantly more frequently with use of the Hot-Axios stent than with the Spaxus stent, although this was not the case for bleeding requiring embolization.

Plastic pigtail vs lumen-apposing metal stents for drainage of walled-off necrosis (PROMETHEUS study): an open-label, multicenter randomized trial

BACKGROUND

Lumen-apposing metal stents (LAMS) have displaced double-pigtail plastic stents (DPS) as the standard treatment for walled-off necrosis (WON),β but evidence for exclusively using LAMS is limited. We aimed to assess whether the theoretical benefit of LAMS was superior to DPS.

METHODS

This multicenter, open-label, randomized trial was carried out in 9 tertiary hospitals. Between June 2017, and Oct 2020, we screened 99 patients with symptomatic WON, of whom 64 were enrolled and randomly assigned to the DPS group (n = 31) or the LAMS group (n = 33). The primary outcome was short-term (4-weeks) clinical success determined by the reduction of collection. Secondary endpoints included long-term clinical success, hospitalization, procedure duration, recurrence, safety, and costs. Analyses were by intention-to-treat.

CLINICALTRIALS

gov, NCT03100578.

RESULTS

A similar clinical success rate in the short term (RR, 1.41; 95% CI 0.88-2.25; p = 0.218) and in the long term (RR, 1.2; 95% CI 0.92-1.58; p = 0.291) was observed between both groups. Procedure duration was significantly shorter in the LAMS group (35 vs. 45-min, p = 0.003). The hospital admission after the index procedure (median difference, - 10 [95% CI - 17.5, - 1]; p = 0.077) and global hospitalization (median difference - 4 [95% CI - 33, 25.51]; p = 0.82) were similar between both groups. Reported stent-related adverse events were similar for the two groups (36 vs.45% in LAMS vs. DPS), except for de novo fever, which was significantly 26% lower in LAMS (RR, 0.26 [0.08-0.83], p = 0.015).

CONCLUSIONS

The clinical superiority of LAMS over DPS for WON therapy was not proved, with similar clinical success, hospital stay and similar safety profile between both groups, yet a significant reduction in procedure time was observed.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT03100578.

Lumen apposing metal stents vs. double pigtail plastic stents for the drainage of pancreatic walled-off necrosis

BACKGROUND

Few studies compared lumen-apposing metal stents (LAMS) and standard double pigtail plastic stents (PS) for the endoscopic drainage of pancreatic walled-off necrosis (WON). Albeit sometimes large, previously described cohorts display considerable heterogeneity and often pooled together data from several centers, involving multiple operators and techniques. Moreover, they often lack a control group for the comparison of outcomes. The aim of this study was to compare clinical efficacy and safety of PS versus LAMS for the endoscopic drainage of infected WON.

METHODS

Thirty patients were enrolled between 2011 and 2017. The present study is a single-center, 1:1 case-control study. We compared patients undergoing endoscopic drainages of infected WON through LAMS (cases) or PS (controls). The primary endpoint was the clinical efficacy (resolution of the WON/sepsis), the secondary endpoint was safety (procedure-related complications).

RESULTS

Cases and controls were homogeneous in terms of etiology and clinical characteristics: 93% of cases and 86.7% of controls were clinically successfully treated, with no significant differences in rates of postoperative infections, bleedings, and stent migrations (respectively 13.3% vs. 21.4%; P=0.65; 13.3% vs. 0%; P=0.48; 13.3% vs. 7.1%; P=1.00). No difference was shown regarding the need for additional percutaneous or surgical treatments (33.3% vs. 13.3%; P=0.39). Cases, however, displayed a significantly prolonged mean hospital stay (90.2 days vs. 18.5 days; P<0.01) and a higher mean number of endoscopic procedures per patient (4.8 vs. 1.5; P<0.01).

CONCLUSIONS

PS might be not inferior to LAMS for the treatment WONs. Further prospective RCT is needed to compare clinical efficacy and safety in the two groups.

Treatment of walled-off necrosis using lumen-apposing metal stents versus plastic stents: a systematic review and meta-analysis of data from randomized trials

BACKGROUND

Walled-off necrosis (WON) is highly morbid disease most effectively managed by endoscopic drainage with lumen-apposing metal stents (LAMSs) or plastic stents, with or without necrosectomy. This meta-analysis compared the clinical outcomes of patients included in randomized trials treated using LAMSs or plastic stents.

METHODS

The MEDLINE and EMBASE databases were searched to identify all data collected from randomized trials comparing LAMSs and plastic stents for the treatment of WON. The primary outcome measure was need for endoscopic necrosectomy.

RESULTS

Three studies comprising 206 patients met inclusion criteria. Except for procedure duration, which was significantly shorter for LAMSs (standardized mean difference [SMD] -1.22, 95%CI -1.64 to -0.79), there was no significant difference in need for necrosectomy (38.5% vs. 41.2%; risk ratio [RR] 1.07, 95%CI 0.79-1.45), number of interventions (SMD -0.09, 95%CI -0.40 to 0.22), treatment success (90.7% vs. 94.5%; RR 0.96, 95%CI 0.87-1.06), recurrence (4.6% vs. 0.6%; RR 3.73, 95%CI 0.42-33.0), readmission (42.6% vs. 50.2%; RR 0.84, 95%CI 0.62-1.14), length of hospitalization (SMD -0.06, 95%CI -0.55 to 0.43), mortality (8.5% vs. 9.8%; RR 0.70, 95%CI 0.30-1.66), new-onset organ failure (10.6% vs. 14.6%; RR 0.72, 95%CI 0.16-3.32), bleeding (11.0% vs. 10.7%; RR 1.09, 95%CI 0.34-3.44), procedural adverse events (23.6% vs. 19.2%; RR 1.38, 95%CI 0.82-2.33), or overall costs (SMD -0.04, 95%CI -0.31 to 0.24) between LAMSs and plastic stents, respectively.

CONCLUSIONS

Except for procedure duration, there is no significant difference in clinical outcomes for patients with WON treated using LAMSs or plastic stents.

Endoscopic Ultrasound-Guided Drainage of Pancreatic Fluid Collections: Not All Queries Are Already Solved

Pancreatic fluid collections (PFCs) are well-known complications of acute pancreatitis. The overinfection of these collections leads to a worsening of the prognosis with an increase in the morbidity and mortality rate. The primary strategy for managing infected pancreatic necrosis (IPN) or symptomatic PFCs is a minimally invasive step-up approach, with endosonography-guided (EUS-guided) transmural drainage and debridement as the preferred and less invasive method. Different stents are available to drain PFCs: self-expandable metal stents (SEMSs), double pigtail stents (DPPSs), or lumen-apposing metal stents (LAMSs). In particular, LAMSs are useful when direct endoscopic necrosectomy is needed, as they allow easy access to the necrotic cavity; however, the rate of adverse events is not negligible, and to date, the superiority over DPPSs is still debated. Moreover, the timing for necrosectomy, the drainage technique, and the concurrent medical management are still debated. In this review, we focus attention on indications, timing, techniques, complications, and particularly on aspects that remain under debate concerning the EUS-guided drainage of PFCs.

Indications, Techniques and Future Perspectives of Walled-off Necrosis Management

Necrotizing pancreatitis is a complex clinical condition burdened with significant morbidity and mortality. In recent years, the huge progress of interventional endoscopic ultrasound (EUS) has allowed a shift in the management of pancreatic necrotic collections from surgical/percutaneous approaches to mini-invasive endoscopic internal drainage and debridement procedures. The development of lumen-apposing metal stents (LAMSs), devices specifically dedicated to transmural EUS interventions, further prompted the diffusion of such techniques. Several studies have reported excellent outcomes of endoscopic interventions, in terms of technical success, clinical efficacy and safety compared to surgical interventions, and thus endoscopic drainage of walled-off necrosis (WON) has become a fundamental tool for the management of such conditions. Despite these advancements, some critical unresolved issues remain. Endoscopic therapeutic approaches to WON are still heterogeneous among different centers and experts. A standardized protocol on indication, timing and technique of endoscopic necrosectomy is still lacking, and experts often adopt a strategy based on personal experience more than robust data from well-conducted studies. In this review, we will summarize the available evidence on endoscopic management of WON and will discuss some unanswered questions in this rapidly evolving field.

Recent Treatment Strategies for Acute Pancreatitis

Acute pancreatitis (AP) is a leading gastrointestinal disease that causes hospitalization. Initial management in the first 72 h after the diagnosis of AP is pivotal, which can influence the clinical outcomes of the disease. Initial management, including assessment of disease severity, fluid resuscitation, pain control, nutritional support, antibiotic use, and endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis, plays a fundamental role in AP treatment. Recent updates for fluid resuscitation, including treatment goals, the type, rate, volume, and duration, have triggered a paradigm shift from aggressive hydration with normal saline to goal-directed and non-aggressive hydration with lactated Ringer's solution. Evidence of the clinical benefit of early enteral feeding is becoming definitive. The routine use of prophylactic antibiotics is generally limited, and the procalcitonin-based algorithm of antibiotic use has recently been investigated to distinguish between inflammation and infection in patients with AP. Although urgent ERCP (within 24 h) should be performed for patients with gallstone pancreatitis and cholangitis, urgent ERCP is not indicated in patients without cholangitis. The management approach for patients with local complications of AP, particularly those with infected necrotizing pancreatitis, is discussed in detail, including indications, timing, anatomical considerations, and selection of intervention methods. Furthermore, convalescent treatment, including cholecystectomy in gallstone pancreatitis, lipid-lowering medications in hypertriglyceridemia-induced AP, and alcohol intervention in alcoholic pancreatitis, is also important for improving the prognosis and preventing recurrence in patients with AP. This review focuses on recent updates on the initial and convalescent management strategies for AP.

Endoscopic management of pancreatic collections. Endoscopic Ultrasound Group from the Spanish Society of Digestive Endoscopy (GSEED-USE) Clinical Guidelines

Acute pancreatitis is associated with significant morbidity and mortality. It can develop complications such as fluid collections and necrosis. Infection of necrosis occurs in about 20-40% of patients with severe acute pancreatitis, and is associated with organ failure and worse prognosis. In the past years, the treatment of pancreatic collections has shifted from open surgery to minimally invasive techniques, such as endoscopic ultrasound guided drainage. These guidelines from a selection of experts among the Endoscopic Ultrasound Group from the Spanish Society of Gastrointestinal Endoscopy (GSEED-USE) have the purpose to provide advice on the management of pancreatic collections based on a thorough review of the available scientific evidence. It also reflects the experience and clinical practice of the authors, who are advanced endoscopists or clinical pancreatologists with extensive experience in managing patients with acute pancreatitis.

Impact of endoprosthesis type on inflammatory response in patients undergoing endoscopic drainage of pancreatic fluid collections

OBJECTIVE

To study the impact of endoprosthesis type on inflammatory response in patients undergoing endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFC).

METHODS

Patients undergoing EUS-guided PFC drainage and treated using lumen-apposing metal stents (LAMS) or plastic endoprostheses constituted the study cohort. The primary outcome was the presence of systemic inflammatory response syndrome (SIRS) after index intervention. Secondary outcomes were persistent organ failure, new onset organ failure, duration of hospitalization, and treatment success.

RESULTS

In all, 303 patients were treated using LAMS (n = 247) or plastic stents (n = 56). At 48 h postintervention, the presence of SIRS (25.0 vs. 14.2%, P = 0.047), new onset SIRS (10.0 vs. 1.8%, P = 0.017), and new organ failure (5.4 vs. 0.4%, P = 0.003) were significantly higher in the plastic stent cohort compared to LAMS. On multivariable logistic regression analysis, the use of plastic stents (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.2-6.0, P = 0.014), patients receiving high-acuity care (OR 5.1, 95% CI 2.5-10.4, P < 0.001) and the presence of ≥33% of necrosis (OR 4.5, 95% CI 2.0-10.0, P < 0.001) were significantly associated with the presence of SIRS or new organ failure. While there was no significant difference in treatment success (96.4 vs. 95.5%, P = 0.77), duration of hospitalization was significantly longer for the plastic stent cohort (mean [standard deviation] 12.5 [17.8] vs. 7.9 [10.1] days, P = 0.009).

CONCLUSIONS

Use of plastic stents as compared to LAMS was associated with a higher proportion of SIRS and new organ failure that prolonged hospital stay. Therefore, placement of LAMS is recommended in sick patients and those with ≥33% necrosis to minimize inflammatory response.

Lumen-apposing metal stents versus traditional self-expanding metal stents for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a systematic review and meta-analysis

BACKGROUND

Endoscopic drainage has become the preferred treatment for pancreatic fluid collections (PFCs). There is still a lack of reliable evidence to prove which metal stent is the best choice for endoscopic ultrasound (EUS)-guided drainage of PFCs. In this study, we aimed to evaluate the efficacy and safety of lumen-apposing metal stents (LAMS) compared to traditional self-expanding metal stents (SEMS) in meta-analysis.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane Library up to July 15, 2023. Relevant publications that compared LAMS with traditional SEMS for drainage of patients' PFCs under EUS-guidance were included. This meta-analysis assessed endpoints using Review Manager 5.3 and Stata 14.0 statistical software.

RESULT

Nine citations comprising 707 patients with PFCs were included. The clinical success rate of LAMS tended to be higher than that of SEMS (RR = 1.07, 95%CI [1.00, 1.15], P = 0.05). LAMS had a lower technical success rate (RR = 0.97, 95%CI [0.94, 0.99], P = 0.02) and faster procedure time (minutes) (MD =  - 24.29, 95%CI [- 25.59, - 22.99], P < 0.00001) compared to SEMS. In addition, LAMS had fewer overall adverse events (RR = 0.64, 95%CI [0.48, 0.87], P = 0.004). For specific adverse events, LAMS had fewer migration (RR = 0.37, 95%CI [0.19, 0.72], P = 0.003), occlusion (RR = 0.43, 95%CI [0.22, 0.82], P = 0.01) and infection (RR = 0.38, 95%CI [0.20, 0.70], P = 0.002). There was no significant difference in bleeding and perforation between the two stents. For hospital stay (days), LAMS group was similar to SEMS group (MD =  - 3.34, 95%CI [- 7.71, - 1.03], P = 0.13). Regarding recurrence, LAMS group was fewer than SEMS group (RR = 0.41, 95%CI [0.21, 0.78], P = 0.007).

CONCLUSION

Compared to traditional SEMS, LAMS has a higher clinical success rate, faster procedure time, fewer adverse events, similar hospital stay and lower recurrence rate in EUS-guided drainage of PFCs. LAMS is a good choice with a high technical success rate over 95%, and using a shorter length or "one-step" operation can further improve it. Richer placement experience is required for LAMS placement under EUS-guidance.

Upfront endoscopic necrosectomy or step-up endoscopic approach for infected necrotising pancreatitis (DESTIN): a single-blinded, multicentre, randomised trial

BACKGROUND

Although the preferred management approach for patients with infected necrotising pancreatitis is endoscopic transluminal stenting followed by endoscopic necrosectomy as step-up treatment if there is no clinical improvement, the optimal timing of necrosectomy is unclear. Therefore, we aimed to compare outcomes between performing upfront necrosectomy at the index intervention versus as a step-up measure in patients with infected necrotising pancreatitis.

METHODS

This single-blinded, multicentre, randomised trial (DESTIN) was done at six tertiary care hospitals (five hospitals in the USA and one hospital in India). We enrolled patients (aged ≥18 years) with confirmed or suspected infected necrotising pancreatitis with a necrosis extent of at least 33% who were amenable to endoscopic ultrasound-guided drainage. By use of computer-generated permuted block randomisation (block size four), eligible patients were randomly assigned (1:1) to receive either upfront endoscopic necrosectomy or endoscopic step-up treatment. Endoscopists were not masked to treatment allocation, but participants, research coordinators, and the statistician were. Lumen-apposing metal stents (20 mm diameter; 10 mm saddle length) were used for drainage in both groups. In the upfront group, direct necrosectomy was performed immediately after stenting in the same treatment session. In the step-up group, direct necrosectomy or additional drainage was done at a subsequent treatment session if there was no clinical improvement (resolution of any criteria of systemic inflammatory response syndrome or sepsis or one or more organ failure and at least a 25% percentage decrease in necrotic collection size) 72 h after stenting. The primary outcome was the number of reinterventions per patient to achieve treatment success from index intervention to 6 months' follow-up, which was defined as symptom relief in conjunction with disease resolution on CT. Reinterventions included any endoscopic or radiological procedures performed for necrosectomy or additional drainage after the index intervention, excluding the follow-up procedure at 4 weeks for stent removal. All endpoints and safety were analysed by intention-to-treat. This study is registered with ClinicalTrials.gov, NCT05043415 and NCT04113499, and recruitment and follow-up have been completed.

FINDINGS

Between Nov 27, 2019, and Oct 26, 2022, 183 patients were assessed for eligibility and 70 patients (24 [34%] women and 46 [66%] men) were randomly assigned to receive upfront necrosectomy (n=37) or step-up treatment (n=33) and included in the intention-to-treat population. At the time of index intervention, seven (10%) of 70 patients had organ failure and 64 (91%) patients had walled-off necrosis. The median number of reinterventions was significantly lower for upfront necrosectomy (1 [IQR 0 to 1] than for the step-up approach (2 [1 to 4], difference -1 [95% CI -2 to 0]; p=0·0027). Mortality did not differ between groups (zero patients in the upfront necrosectomy group vs two [6%] in the step-up group, difference -6·1 percentage points [95% CI -16·5 to 4·5]; p=0·22), nor did overall disease-related adverse events (12 [32%] patients in the upfront necrosectomy group vs 16 [48%] patients in the step-up group, difference -16·1 percentage points [-37·4 to 7·0]; p=0·17), nor procedure-related adverse events (four [11%] patients in the upfront necrosectomy group vs eight [24%] patients in the step-up group, difference -13·4 percentage points [-30·8 to 5·0]; p=0·14).

INTERPRETATION

In stabilised patients with infected necrotising pancreatitis and fully encapsulated collections, an approach incorporating upfront necrosectomy at the index intervention rather than as a step-up measure could safely reduce the number of reinterventions required to achieve treatment success.

FUNDING

None.

Endoscopic ultrasound-guided drainage of early pancreatic necrotic collection: Single-center retrospective study

BACKGROUND

Endoscopic ultrasound (EUS)-guided drainage is the standard of care for drainage of pancreatic necrosis. Though initially it was mainly used for drainage of only walled-off necrosis, recently, a few studies have also shown its safety in the management of acute necrotic collections. We did a retrospective study to evaluate the safety and efficacy of EUS-guided drainage in the early phase of pancreatitis as compared to interventions in the late phase.

METHODS

We retrieved baseline disease-related, procedure-related and outcome-related details of patients who underwent EUS-guided drainage of pancreatic necrosis. Patients were divided into early (≤ 28 days from onset of pancreatitis) or delayed (> 28 days) drainage groups. Both groups were compared for disease-related characteristics and outcomes.

RESULTS

Total 101 patients were included in the study. The mean age of included patients was 35.54 ± 13.58 years and 75 were male. Thirty-five patients (34.7%) underwent early drainage. In the early group, a majority of patients underwent intervention due to infected collection (88.6% vs. 18.2%; p < 0.001). More patients in the early group had < 30% wall formation (28.6% vs. 0%; p < 0.001) and > 30% solid debris within the collection (42.9% vs. 15.2%; p = 0.005). Patients in the early group were also more likely to require endoscopic necrosectomy (57.1% vs. 27.3%; p = 0.003) and additional percutaneous drainage (31.4% vs. 12.1%; p = 0.018). Overall, three patients in the early group and one patient in the delayed group had procedure-related complications. Four patients in the early group and one patient in the delayed group succumbed to illness (p = 0.029).

CONCLUSION

Though delayed interventions remain standard of care in the management of acute pancreatitis, some patients may require early intervention due to infected collection with deteriorating clinical status. Early EUS-guided interventions in such carefully selected patients have in similar clinical outcomes and complication rates compared to delayed intervention. However, such patients are more likely to require additional endoscopic or percutaneous interventions.

An expensive gastric piercing: an embedded lumen-apposing metal stent

Video 1Narration of case and demonstration of the endoscopic management of an embedded stent with stent-in-stent technique to induce pressure necrosis, followed by a combination of needle-knife electroincision, argon plasma coagulation, stent intubation and transection with the gastroscope shaft, and cold and hot snare resection.

Managing complications of chronic pancreatitis: a guide for the gastroenterologist

INTRODUCTION

Chronic pancreatitis is a heterogeneous and complex syndrome that, in most cases, causes pain as a cardinal symptom and affects both the morphology and function of the pancreas, leading to several serious complications.

AREAS COVERED

The present review, based on a non-systematic PubMed search updated to June 2023, aims to present the current available evidence on the role of gastroenterologists in the diagnosis and treatment of both local and systemic complications by either endoscopic or medical treatments.

EXPERT OPINION

At diagnosis and during chronic pancreatitis follow-up, particular care is needed to consider not only the clinically manifest signs and symptoms of the disease, such as pain, jaundice, gastrointestinal obstruction, and pseudocysts, which require multidisciplinary discussion to establish the best treatment option (endoscopic or surgical), but also less evident systemic complications. Pancreatic exocrine and endocrine insufficiency, together with chronic inflammation, addiction, and dysbiosis, contribute to malnutrition, sarcopenia, and osteopathy. These complications, in turn, increase the risk of infection, thromboembolic events, and death. Patients with chronic pancreatitis also have an increased risk of psychiatric disorders and pancreatic cancer onset. Overall, patients with chronic pancreatitis should receive a holistic evaluation, considering all these aspects, possibly through multidisciplinary care in dedicated expert centers.

Safety and efficacy of lumen-apposing metal stents and double-pigtail plastic stents for endoscopic ultrasound-guided drainage of walled-off necrosis; a systematic review and meta-analysis

BACKGROUND

Patients with walled-off necrosis (WON) are still challenging to treat safely and effectively. Recently, double-pigtail plastic stents (DPS), bi-flanged metallic stents (BFMS), and lumen-apposing metal stents (LAMS) have been employed with endoscopic ultrasound-guided (EUS-guided) drainage. However, there is little solid evidence to support the effectiveness and safety of using stents. This study aims to compare the outcomes of the LAMS and the PS.

METHOD

Till July 2022, a thorough database search was done, and studies that met the criteria were chosen. By using the RevMan software, the technical and clinical success and other secondary outcomes were calculated. Subgroup analysis was performed between the LAMS and the BFMS.

RESULTS

Fifteen studies (two randomized controlled trials and thirteen observational) with 687 patients receiving metal stents and 771 patients receiving plastic stents were selected for final analysis. There was no significant risk of bias or publication bias. The odds ratios (OR) for technical and clinical success were 0.36 (95% confidence interval (95% CI) 0.08, 1.52) and 2.26 (95%CI 1.62, 3.15), respectively. The OR for overall adverse events was 0.74 (95% CI 0.41, 1.34). In subgroup analysis, the LAMS and the BFMS showed the same outcomes.

CONCLUSION

Compared to DPS, LAMS had better clinical outcomes and fewer side effects when treating patients with WON.

Clinical application and follow-up of electrocautery-enhanced lumen-apposing metal stents for endoscopic ultrasonography-guided interventions

Aim: The lumen-apposing metal stent (LAMS) is a new device that expands the scope of gastrointestinal intervention under endoscopy. LAMS was initially used for the treatment of pancreatic fluid collections (PFCs), but is increasingly being used off-label. The electrocautery system simplifies the deployment of LAMS, making it more suitable for off-label situations. The short-term results of electrocautery-enhanced lumen-apposing metal stents (ECE-LAMS) are satisfactory; however, the long-term follow-up results must be evaluated. The aim of this article is to review the expanded clinical application of ECE-LAMS, the clinical value of on-label and off-label use, and follow-up results.Methods: After searching in PubMed and Web of Science databases using 'electrocautery-enhanced lumen-apposing metal stents' and 'endoscopic ultrasonography (EUS) -guided interventions' as keywords, studies related were compiled and examined.Results: ECE-LAMS are widely used for on-label and off-label situations. The short-term and long-term results of ECE-LAMS are satisfactory, but there are still some studies that do not agree with this viewpoint.Conclusion: The clinical application of ECE-LAMS is relatively safe and reliable but more well-designed randomized trials and prospective studies are needed to evaluate the impact of this technology on therapeutic EUS, to improve the safety and success rate of EUS-guided LAMS implantation, and to expand its application in other indications.

Plastic versus metal stents for transmural drainage of walled-off necrosis with significant solid debris: a randomized controlled trial

Background and study aims Recently, larger-caliber metal stents have been increasingly used, resulting in higher efficacy in walled-off necrosis (WON) with more solid debris. However, none of the trials have included WON with significant solid debris. The aim of this study was to compare plastic stents and metal stents for drainage of symptomatic WON with significant solid debris (≥20%). Patients and methods We conducted a single-center, open-label, noninferiority trial including 48 patients. The primary endpoint was treatment success. Secondary outcomes were technical success, total number of procedures, adverse events (AEs), duration of procedure, and treatment failure. All the outcomes were assessed at 3 weeks after drainage. Patients were followed up for 3 months to assess recurrence. Results Treatment succeeded in 21 of 24 patients (87.5%) and 20 of 24 patients (83.3%) in the metal and plastic stent groups, respectively with P =1.05 (95% confidence interval 0.81-1.39). Assuming 10% non-inferiority margin, P <0.001 for non-inferiority, suggesting that plastic stents are non-inferior to metal stents. The technical success rate was 100%. Procedure duration was significantly shorter in the metal stent group (12.95±5.3 minutes versus 29.77±6.6 minutes, P <0.001). The number of total procedures was comparable (2.8±1 vs 2.2±1, P =0.097). There were more minor AEs in plastic stent arm but no significant difference between the two groups. A single asymptomatic recurrence was observed in the metal stent arm. Conclusions Plastic stents are not inferior to metal stents for WON drainage with significant solid debris. However, larger sample-size studies are needed to make definite conclusions.

Endoscopic transgastric fenestration versus percutaneous drainage for management of (peri)pancreatic fluid collections adjacent to gastric wall (with video)

BACKGROUND

Percutaneous drainage (PCD) and endoscopic approaches have largely replaced surgical drainage as the initial approach for (peri) pancreatic fluid collections (PFC)s, while complications associated with endoscopic stent implantation are common.

AIM

To introduce a novel endoscopic therapy named endoscopic transgastric fenestration (ETGF), which involves resection of tissue by endoscopic accessory between gastric and PFCs without stent implantation, and to evaluate its efficacy and safety compared with PCD for the management of PFCs adjacent to the gastric wall.

METHODS

Patients diagnosed with PFCs adjacent to the gastric wall and who subsequently received ETGF or PCD were restrospectively enrolled. Indications for intervention were consistent with related guidelines. We analyzed patients baseline characteristics, technical and clinical success rate, recurrence and reintervention rate, procedure-related complications and adverse events.

RESULTS

Seventy-two eligible patients were retrospectively identified (ETGF = 34, PCD = 38) from October 2017 to May 2021. Patients in the ETGF group had a significantly higher clinical success rate than those in the PCD group (97.1 vs 76.3%, P = 0.01). There were no statistically significant differences regarding recurrence, reintervention and incidence of complication between the two groups. While long-term catheter drainage was very common in the PCD group.

CONCLUSION

Compared with PCD, ETGF has a higher clinical success rate in the management of PFCs adjacent to the gastric wall. ETGF is an alternative effective strategy for the treatment of PFCs adjacent to the gastric wall.

Endoscopic Ultrasound Guided Walled-off Necrosis Drainage

Walled-off necrosis is a well-recognized complication of necrotizing pancreatitis that can cause sepsis, luminal or ductal obstruction, or persistent unwellness requiring multidisciplinary care. Recent data suggest that minimally invasive endoscopic treatment strategies are preferred over more invasive surgical approaches. Although endoscopic transmural drainage with or without necrosectomy is the primary approach for patients requiring an intervention, for collections not amenable to endoscopic approach, percutaneous drain placement followed by video-assisted retroperitoneal debridement or laparoscopic cystogastrostomy with internal debridement are other alternatives. More studies are required to optimize post-procedure care to shorten the length of stay and minimize resource utilization.

Interventional Endoscopic Ultrasound: Current Status and Future Frontiers

Interventional endoscopic ultrasound has fueled remarkable advancements in the field of therapeutic procedures, revolutionizing minimally invasive interventions for a diverse range of conditions. This review highlights the latest breakthroughs and advancements in therapeutic endoscopic ultrasound, showcasing its potential to transform patient care.

Endoscopic Ultrasound in Pancreatology: Focus on Inflammatory Diseases and Interventions

Background

Endoscopic ultrasound (EUS) is a main tool in pancreatology for both diagnosis and therapy. It allows minimally invasive differentiation of various diseases, with a minimal degree of inflammation or anatomic variations. EUS also enables interventional direct access to the pancreatic parenchyma and the retroperitoneal space, the pancreatic duct, the pancreatic masses, cysts, vascular structures for diagnostic and therapeutic purposes.

Summary

This review aimed to summarize the new developments of EUS in the field of pancreatology, with special interest on inflammation and interventions. EUS enables way to perform pseudocyst drainage, necrosectomy, transenteral drainage and transenteric access of the main pancreatic duct, or the direct visualization or therapy of vascular structures adjacent to the pancreas.

Key Messages

EUS has a deep impact on pancreatology, and the development of new diagnostic and interventional approaches to the retroperitoneal space and the pancreas has increased in the last years exponentially, allowing minimal invasive diagnostics and therapy and avoiding surgery and percutaneous therapy.

Time to think prime times for treatment of necrotizing pancreatitis: Pendulum conundrum

Pancreatic fluid collections (PFCs) typically develop as local complications of acute pancreatitis and complicate the clinical course of patients with acute pancreatitis and potentially fatal clinical outcomes. Interventions are required in cases of symptomatic walled-off necrosis (WON) (matured PFCs with necrosis) and pancreatic pseudocysts (matured PFCs without necrosis). In the management of necrotizing pancreatitis and WON, endoscopic ultrasound-guided transluminal drainage combined with on-demand endoscopic necrosectomy (i.e. the step-up approach) is increasingly used as a less invasive treatment modality compared with a surgical or percutaneous approach. Through the substantial research efforts and development of specific devices and stents (e.g. lumen-apposing metal stents), endoscopic techniques of PFC management have been standardized to some extent. However, there has been no consensus about timing of carrying out each treatment step; for instance, it is uncertain when direct endoscopic necrosectomy should be initiated and finished and when a plastic or metal stent should be removed following clinical treatment success. Despite emerging evidence for the effectiveness of noninterventional supportive treatment (e.g. antibiotics, nutritional support, irrigation of the cavity), there has been only limited data on the timing of starting and stopping the treatment. Large studies are required to optimize the timing of those treatment options and improve clinical outcomes of patients with PFCs. In this review, we summarize the current available evidence on the indications and timing of interventional and supportive treatment modalities for this patient population and discussed clinical unmet needs that should be addressed in future research.

Mishaps with EUS-guided lumen-apposing metal stents in therapeutic pancreatic EUS: Management and prevention

EUS-guided interventions have become widely accepted therapeutic management options for drainage of peripancreatic fluid collections. Apart from endosonographic skills, EUS interventions require knowledge of the endoscopic stenting techniques and familiarity with the available stents and deployment systems. Although generally safe and effective, technical failure of correct stent positioning or serious adverse events can occur, even in experts' hands. In this article, we address common and rare adverse events in transmural EUS-guided stenting, ways to prevent them, and management options when they occur. Knowing the risks of what can go wrong combined with clinical expertise, high levels of technical skills, and adequate training allows for the safe performance of EUS-guided drainage procedures. Discussing the procedural risks and their likelihood with the patient is a fundamental part of the consenting process.

Best Practices in Pancreatico-biliary Stenting and EUS-guided Drainage

Indications for endoscopic placement of endoluminal and transluminal stents have greatly expanded over time. Endoscopic stent placement is now a well-established approach for the treatment of benign and malignant biliary and pancreatic diseases (ie, obstructive jaundice, intra-abdominal fluid collections, chronic pancreatitis etc.). Ongoing refinement of technical approaches and development of novel stents is increasing the applicability and success of pancreatico-biliary stenting. In this review, we discuss the important developments in the field of pancreatico-biliary stenting, with a specific focus on endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-associated developments.

Endoscopic removal of lumen-apposing metal stents - risk factors for stent embedment, complex removals, and adverse events: analysis from a multicenter prospective case series

BACKGROUND

Removing lumen-apposing metal stents (LAMSs) may be difficult and even harmful, but these features have seldom been analyzed. We aimed to generate a comprehensive assessment of the feasibility and safety of LAMS retrieval procedures.

METHODS

A prospective multicenter case series including all technically successfully deployed LAMSs between January 2019 and January 2020 that underwent endoscopic stent removal. All retrieval-related data were prospectively recorded using standardized telephone questionnaires as part of centralized follow-up that ended after stent removal had been performed. Multivariable logistic regression models assessed the potential risk factors for complex removal.

RESULTS

For the 407 LAMSs included, removal was attempted in 158 (38.8 %) after an indwell time of 46.5 days (interquartile range [IQR] 31-70). The median (IQR) removal time was 2 (1-4) minutes. Removal was labelled as complex in 13 procedures (8.2 %), although advanced endoscopic maneuvers were required in only two (1.3 %). Complex removal risk factors were stent embedment (relative risk [RR] 5.84, 95 %CI 2.14-15.89; P = 0.001), over-the-wire deployment (RR 4.66, 95 %CI 1.60-13.56; P = 0.01), and longer indwell times (RR 1.14, 95 %CI 1.03-1.27; P = 0.01). Partial and complete embedment were observed in 14 (8.9 %) and five cases (3.2 %), respectively. The embedment rate during the first 6 weeks was 3.1 % (2/65), reaching 15.9 % (10/63) during the following 6 weeks (P = 0.02). The adverse event rate was 5.1 %, including seven gastrointestinal bleeds (5 mild, 2 moderate).

CONCLUSIONS

LAMS removal is a safe procedure, mostly requiring basic endoscopic techniques attainable in conventional endoscopy rooms. Referral to advanced endoscopy units should be considered for stents with known embedment or long indwell times, which may require more technically demanding procedures.

Evolution of interventional endoscopic ultrasound

Endoscopic ultrasound (EUS) has become an indispensable modality for the assessment of the gastrointestinal tract and adjacent structures since its origin in the 1980s. Following the development of the linear echoendoscope, EUS has evolved from a purely diagnostic modality to a sophisticated tool for intervention, with numerous luminal, pancreaticobiliary, and hepatic applications. Broadly, these applications may be subdivided into three categories: transluminal drainage or access procedures, injection therapy, and EUS-guided liver interventions. Transluminal drainage or access procedures include management of pancreatic fluid collection, EUS-guided biliary drainage, EUS-guided bile duct drainage, EUS-guided pancreatic duct drainage, and enteral anastomosis formation. Injection therapies include therapeutic EUS-guided injections for management of malignancies accessible by EUS. EUS-guided liver applications include EUS-guided liver biopsy, EUS-guided portal pressure gradient measurement, and EUS-guided vascular therapies. In this review, we discuss the origins of each of these EUS applications, evolution of techniques leading to the current status, and future directions of EUS-guided interventional therapy.

Transpapillary Stenting Improves Treatment Outcomes in Patients Undergoing Endoscopic Transmural Drainage of Ductal Disruption-Associated Pancreatic Fluid Collections

INTRODUCTION

Endoscopic transmural drainage (TMD) has been accepted as the preferred therapy for symptomatic pancreatic fluid collections (PFCs). Recurrence of PFCs presents a unique challenge in patients with disrupted pancreatic duct (PD). We aimed to evaluate whether transpapillary drainage (TPD) provides additional benefits to TMD in patients with PD disruption.

METHODS

This was a multicenter retrospective study. Consecutive patients who underwent TMD, TPD, or combined drainage (CD) of PFCs were included. The primary outcome was to compare PFC recurrence among different groups. The secondary outcomes were the technical success rate, length of hospital stay, and procedure-related complications.

RESULTS

A total of 153 patients, which consists of 57 patients with pancreatic pseudocysts and 96 patients with walled-off necrosis, were included. PFC recurrence was more common in patients with PD disruption than those with an intact main duct (19% vs 1.4%, P < 0.001). PD disruption was identified as a major risk factor of PFC recurrence by univariable and multivariable analyses. The recurrence rate of CD was significantly lower than TMD only or TPD only (6.5% vs 15.4% vs 22.7%, P < 0.01). The length of hospital stay of CD was significantly shorter than TMD only or TPD only (5 [3.0-9.0] vs 7.0 [5.0-12.0] vs 9 [7.0-16.0], P < 0.001). Dual-modality drainage did not increase procedure-related complications compared with TMD only (13.0% vs 12.8%, P > 0.05). Partial PD disruption was bridged in 87.3% cases while complete PD disruption was reconnected in 55.2% cases. Although statistically not significant, the clinical success rate in walled-off necrosis cases with actively bridged ducts was much higher than those with passively bridged ducts (76.9% vs 40%).

DISCUSSION

Transpapillary pancreatic duct stenting seems to improve the efficacy of endoscopic TMD of pancreatic duct disruption-associated PFCs by reducing the recurrence rate and shortening the length of hospital stay.

WONDER-01: immediate necrosectomy vs. drainage-oriented step-up approach after endoscopic ultrasound-guided drainage of walled-off necrosis-study protocol for a multicentre randomised controlled trial

BACKGROUND

With the increasing popularity of endoscopic ultrasound (EUS)-guided transmural interventions, walled-off necrosis (WON) of the pancreas is increasingly managed via non-surgical endoscopic interventions. However, there has been an ongoing debate over the appropriate treatment strategy following the initial EUS-guided drainage. Direct endoscopic necrosectomy (DEN) removes intracavity necrotic tissue, potentially facilitating early resolution of the WON, but may associate with a high rate of adverse events. Given the increasing safety of DEN, we hypothesised that immediate DEN following EUS-guided drainage of WON might shorten the time to WON resolution compared to the drainage-oriented step-up approach.

METHODS

The WONDER-01 trial is a multicentre, open-label, superiority, randomised controlled trial, which will enrol WON patients aged ≥ 18 years requiring EUS-guided treatment in 23 centres in Japan. This trial plans to enrol 70 patients who will be randomised at a 1:1 ratio to receive either the immediate DEN or drainage-oriented step-up approach (35 patients per arm). In the immediate DEN group, DEN will be initiated during (or within 72 h of) the EUS-guided drainage session. In the step-up approach group, drainage-based step-up treatment with on-demand DEN will be considered after 72-96 h observation. The primary endpoint is time to clinical success, which is defined as a decrease in a WON size to ≤ 3 cm and an improvement of inflammatory markers (i.e. body temperature, white blood cell count, and C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, and recurrence of the WON.

DISCUSSION

The WONDER-01 trial will investigate the efficacy and safety of immediate DEN compared to the step-up approach for WON patients receiving EUS-guided treatment. The findings will help us to establish new treatment standards for patients with symptomatic WON.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05451901, registered on 11 July 2022. UMIN000048310, registered on 7 July 2022. jRCT1032220055, registered on 1 May 2022.

Combined Drainage and Protocolized Necrosectomy Through a Coaxial Lumen-apposing Metal Stent for Pancreatic Walled-off Necrosis: A Prospective Multicenter Trial

OBJECTIVE

We evaluated a protocolized endoscopic necrosectomy approach with a lumen-apposing metal stent (LAMS) in patients with large symptomatic walled-off pancreatic necrosis (WON) comprising significant necrotic content, with or without infection.

SUMMARY BACKGROUND DATA

Randomized trials have shown similar efficacy of endoscopic treatment compared with surgery for infected WON.

DESIGN

We conducted a regulatory, prospective, multicenter single-arm clinical trial examining the efficacy and safety of endoscopic ultrasound -guided LAMS with protocolized necrosectomy to treat symptomatic WON ≥6 cm in diameter with >30% solid necrosis. After LAMS placement, protocolized WON assessment was conducted and endoscopic necrosectomy was performed for insufficient WON size reduction and persistent symptoms. Patients with radiographic WON resolution to ≤ 3 cm and/or 60-day LAMS indwell had LAMS removal, then 6-month follow-up. Primary endpoints were probability of radiographic resolution by 60 days and procedure-related serious adverse events.

RESULTS

Forty consecutive patients were enrolled September 2018 to March 2020, of whom 27 (67.5%) were inpatients and 19 (47.5%) had clinical evidence of infection at their index procedure. Mean WON size was 15.0 ± 5.6 cm with mean 53.2% ± 16.7% solid necrosis. Radiographic WON resolution was seen in 97.5% (95% CI, 86.8%, 99.9%) by 60 days, without recurrence in 34 patients with 6-month follow-up data. Mean time to radiographic WON resolution was 34.1 ± 16.8 days. Serious adverse events occurred in 3 patients (7.5%), including sepsis, vancomycin-resistant enterococcal bacteremia and shock, and upper gastrointestinal bleeding. There were no procedure-related deaths.

CONCLUSIONS

Endoscopic ultrasound-guided drainage with protocolized endoscopic necrosectomy to treat large symptomatic or infected walled-off necrotic pancreatic collections was highly effective and safe. Clinicaltrials.-gov no: NCT03525808.