Predicting the Need for Step-Up Therapy After EUS-Guided Drainage of Pancreatic Fluid Collections With Lumen-Apposing Metal Stents

Necrosectomy and its timing in relation to clinical outcomes of EUS-guided treatment of walled-off pancreatic necrosis: a multicenter study

BACKGROUND AND AIMS

EUS-guided transmural drainage with on-demand endoscopic necrosectomy (EN) is increasingly used to manage walled-off necrosis (WON). It has not been fully elucidated how EN and its timing are correlated with treatment outcomes compared with the drainage-based approach.

METHODS

Within a multi-institutional cohort of 423 patients with pancreatic fluid collections, including 227 patients with WON, 153 patients were identified who received the step-up treatment after the initial EUS-guided drainage of symptomatic WON; this included 102 EN patients and 51 non-EN (drainage) patients. Using the competing-risks multivariable proportional hazards regression model with adjustment for potential confounders, we calculated subdistribution hazard ratios (SHRs) for clinical treatment success (WON resolution) according to use of EN and its timing.

RESULTS

Compared with drainage alone, the EN-based treatment was associated with a shorter time to clinical success with a multivariable SHR of 1.66 (95% confidence interval, 1.12-2.46). Despite a higher risk of procedure-related bleeding in the EN group, there were no differences in the rates of severe adverse events (7.8% vs 5.9% in the EN and non-EN groups, respectively) or mortality (6.9% vs 9.8%). In the EN-treated patients, the timing of EN was not statistically significantly associated with the time to clinical success (Ptrend = .34).

CONCLUSIONS

Among patients receiving EUS-guided treatment of symptomatic WON, the use of EN in addition to drainage procedures was associated with earlier disease resolution. Further research is desired to determine the optimal timing of initiating EN considering a risk-benefit balance and cost-effectiveness.

Approach to the Diagnosis and Management of Infected Pancreatic Necrosis: A Narrative Review

Infected pancreatic necrosis (IPN) is a dreaded complication of acute necrotizing pancreatitis and is linked to persistent organ failure, sepsis, and increased morbidity and mortality. Clinical indicators of IPN include fever, clinical deterioration, and worsening inflammatory markers. The diagnosis of IPN is based on clinical signs, microbiological confirmation, and radiological evidence, with contrast-enhanced CT being the preferred imaging modality. In the absence of tests with high sensitivity, a high clinical suspicion is required for early recognition and treatment. Although there is no way to prevent IPN, a systematic management approach with parenteral antibiotics, nutritional management, and minimally invasive procedures has become the cornerstone of the treatment. The step-up approach includes minimally invasive procedures that minimize procedure-related complications and are associated with improved outcomes. The percutaneous route remains the most common route for drainage, while endoscopic interventions are preferred for perigastric or periduodenal encapsulated collections. The use of lumen-apposing metal stents is associated with excellent outcomes in cases of infected walled-off necrosis. Patients with significant quantities of infected necrosis may benefit from direct or percutaneous endoscopic necrosectomy. Minimally invasive surgical techniques followed by open surgeries are reserved for patients who do not improve with percutaneous or endoscopic necrosectomies. The outcome can be maximized through a multidisciplinary approach by a team of interventional radiologists, advanced therapeutic endoscopists, and surgeons.

Comorbidity burden and outcomes of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Multicenter study with nationwide data-based validation

OBJECTIVES

The appropriate holistic management is mandatory for successful endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs). However, comorbidity status has not been fully examined in relation to clinical outcomes of this treatment.

METHODS

Using a multi-institutional cohort of 406 patients receiving EUS-guided treatment of PFCs in 2010-2020, we examined the associations of Charlson Comorbidity Index (CCI) with in-hospital mortality and other clinical outcomes. Multivariable logistic regression analysis was conducted with adjustment for potential confounders. The findings were validated using a Japanese nationwide inpatient database including 4053 patients treated at 486 hospitals in 2010-2020.

RESULTS

In the clinical multi-institutional cohort, CCI was positively associated with the risk of in-hospital mortality (Ptrend < 0.001). Compared to patients with CCI = 0, patients with CCI of 1-2, 3-5, and ≥6 had adjusted odds ratios (95% confidence intervals) of 0.76 (0.22-2.54), 5.39 (1.74-16.7), and 8.77 (2.36-32.6), respectively. In the nationwide validation cohort, a similar positive association was observed; the corresponding odds ratios (95% confidence interval) were 1.21 (0.90-1.64), 1.52 (0.92-2.49), and 4.84 (2.63-8.88), respectively (Ptrend < 0.001). The association of higher CCI with longer length of stay was observed in the nationwide cohort (Ptrend < 0.001), but not in the clinical cohort (Ptrend = 0.18). CCI was not associated with the risk of procedure-related adverse events.

CONCLUSIONS

Higher levels of CCI were associated with a higher risk of in-hospital mortality among patients receiving EUS-guided treatment of PFCs, suggesting the potential of CCI in stratifying the periprocedural mortality risk.

TRIAL REGISTRATION

The research based on the clinical data from the WONDERFUL cohort was registered with UMIN-CTR (registration number UMIN000044130).

The role of MRCP for preventing pancreatic fluid collection recurrence after EUS-guided drainage of walled-off necrosis

BACKGROUND AND AIMS

Pancreatic fluid collections (PFCs) may recur after initial successful endoscopic drainage of walled-off necrosis (WON), most commonly due to disconnected pancreatic duct syndrome (DPDS). The primary aim of this study was to assess the role of MRCP for identifying DPDS to guide appropriate management and prevent PFC recurrence.

METHODS

Patients with WON undergoing lumen-apposing metal stent drainage of a PFC were retrospectively identified and categorized as those with MRCP versus those without MRCP before removal of transmural stents. Data on patient demographic characteristics, procedural details, cross-sectional imaging, and recurrence rates were collected through chart review.

RESULTS

A total of 121 patients with WON were identified, of whom 44 (36.4%) had an MRCP before transmural stent removal. In patients without MRCP, 13 (16.8%) of 77 had PFC recurrence versus 0 of 44 (0%; P = .003) in those with MRCP. MRCP identified DPDS in 12 (27.2%) patients, all of whom were managed with indefinite drainage with double-pigtail plastic stents without recurrence. In the group without MRCP, PFCs recurred at a median interval of 284 days (interquartile range, 182-618 days) after transmural stent removal. Among the 13 patients with PFC recurrence, 11 (85%) had undiagnosed DPDS detected on subsequent imaging, of whom 9 were subsequently managed with indefinite double-pigtail plastic stents, with no further PFC recurrence.

CONCLUSIONS

Patients with WON who underwent MRCP before transmural stent removal had a lower rate of PFC recurrence largely due to the identification of DPDS with appropriate endoscopic management.

Endoscopic Step-Up Approach in Management of Necrotizing Pancreatitis

The endoscopic step-up approach in the management of necrotizing pancreatitis involves sequential steps of intervention at different time points in the clinical course of the disease. EUS -guided drainage of walled-off necrosis is the first step of the endoscopic step-up approach. Lumen-apposing metal stents are preferred over plastic stents for safe and effective drainage because of their wide caliber. Successive steps in the endoscopic step-up approach include direct endoscopic necrosectomy and/or irrigation using naso-cystic tube in symptomatic patients, primarily based on necrotic debris characteristics. Minimally invasive percutaneous radiological and/or surgical drainage are considered when endoscopic drainage is not feasible or successful.

Pancreatic necrosis: a scoping review

Acute pancreatitis (AP) is a commonly encountered GI diagnosis, accounting for 275,000 hospital admissions annually in the United States alone. Pancreatic necrosis (PN) is the most common complication of AP, and the development of PN is associated with significant morbidity and increased mortality. This expert review evaluates the evidence-based management of symptomatic PN from the era of maximal open pancreatic necrosectomy in the late 1990s though the modern paradigm of minimally invasive and endoscopic interventions. The authors present the retrospective and controlled data behind the "step-up approach" to PN treatment and discuss the application of current society guidance. Evidence based management of PN is characterized by early supportive care, and treatment by minimally invasive intervention when a patient is critically ill or persistently symptomatic. Appropriate choices when intervention is required include percutaneous drainage, minimally invasive surgery, and/or endoscopic treatment. The transition from open maximal necrosectomy to minimally invasive intervention has resulted in improved outcomes for patients, including gains in mortality, significant morbidity, and cost. The ideal precision management strategy for an individual patient remains an area of increasing understanding.

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.

Updates on therapeutic endoscopic ultrasound

PURPOSE OF REVIEW

Multiple endoscopic ultrasound (EUS) guided therapeutic interventions have been developed for the management of benign and malignant pancreaticobiliary and gastrointestinal luminal pathology. Recent high-quality evidence is increasingly validating these interventions and positioning them within evidence-based therapeutic algorithms.

RECENT FINDINGS

Here we review therapeutic EUS-guided interventions including pancreatic fluid collection drainage, gastroenterostomy, biliary drainage, pancreatic duct drainage and gallbladder drainage. The most up-to-date high-quality evidence supporting these interventions is presented including comparative data with other conventional treatment options. Newer emerging interventions such as tumor ablation are also reviewed. Current controversies and future avenues for research are discussed. The key role of EUS-guided interventions in managing pancreaticobiliary pathology in patients with a surgically altered anatomy is highlighted.

SUMMARY

Multiple EUS therapeutic interventions have evolved from experimental or rescue options to now well established first- and second-line interventions over other endoscopic, percutaneous and surgical alternatives with the support of high-quality data. Further research is needed to better optimize patient selection and guide long term postintervention follow-up.

Therapeutic Endoscopic Ultrasound and Endoscopic Ultrasound-Endoscopic Retrograde Cholangiopancreatography Interventions

Therapeutic endoscopic ultrasound (EUS) encompasses an array of procedures to manage pancreaticobiliary and luminal gastrointestinal disorders. Therapeutic EUS procedures include EUS-guided rendezvous of the pancreatic and biliary ducts, as well as direct drainage of the bile duct, pancreatic duct, and gallbladder, drainage of pancreatic fluid collections, and luminal anastomosis creation. These procedures have a range of required equipment, approaches, clinical outcomes, and adverse events dependent on both procedure-related and patient-related factors. In expert hands, these procedures provide patients with less invasive options and can achieve excellent clinical outcomes.

A comparison of novel electrocautery-enhanced lumen-apposing metal stents and plastic stents in endoscopic ultrasound-guided drainage of infected walled-off necrosis: a multicenter randomized study

BACKGROUND

Although lumen-apposing metal stents (LAMSs) have been increasingly used for walled-off necrosis (WON), their advantages over plastic stents in infected WON are unclear. We investigated the safety and efficacy of a novel electrocautery-enhanced LAMS for managing infected WON.

METHODS

Patients who required endoscopic ultrasound-guided WON drainage were randomly assigned to LAMS or plastic stent groups. The primary outcome was total number of direct endoscopic necrosectomy (DEN) procedures required to achieve clinical success. Secondary outcomes included rates of technical success, clinical success, and adverse events.

RESULTS

46 patients were included in the LAMS (n = 23) and plastic stent (n = 23) groups. The median total number of DEN procedures did not differ significantly between the plastic stent group (4 procedures, interquartile range [IQR] 2.5-5.0) and LAMS group (9 procedures, IQR 8.0-9.0) (P = 0.07). The LAMS group demonstrated a significantly higher clinical success rate than the plastic stent group based on intention-to-treat analysis (100% vs. 73.9%, P =0.03) at 8 weeks but not at 4 weeks. Significant bleeding occurred in one patient in the plastic stent group and no patients in the LAMS group.

CONCLUSIONS

We found no significant difference in the total number of DEN procedures between LAMSs and plastic stents for managing infected WON. The only statistically significant finding was a higher clinical success rate at 8 weeks for patients treated with LAMS. The use of LAMS did not result in any adverse events, such as bleeding or buried LAMS syndrome, within the study duration.

Practical approach to acute pancreatitis: from diagnosis to the management of complications

The purpose of this review is to provide a practical guide for the clinical care of patients with acute pancreatitis (AP) from the management of the early phases of disease to the treatment of local complications. AP is one of the most frequent causes of gastroenterological admission in emergency departments. It is characterized by a dynamic and unpredictable course and in its most severe forms, is associated with organ dysfunction and/or local complications, requiring intensive care with significant morbidity and mortality. Initial therapy includes adequate fluid resuscitation, nutrition, analgesia, and when necessary critical care support. In recent years, the development of minimally invasive tailored treatments for local complications, such as endoscopic drainage, has improved patients' acceptance and outcomes. Despite this, the management of AP remains a challenge for clinicians. The present review was conducted by the authors, who formulated specific questions addressing the most critical and current aspects of the clinical course of AP with the aim of providing key messages.

The i-EUS consensus on the management of pancreatic fluid collections - Part 1

Pancreatic fluid collections (PFCs), including pancreatic pseudocysts (PPs) and walled-off pancreatic necrosis (WON), are common complications of pancreatitis and pancreatic surgery. Historically, the treatment of these conditions has relied on surgical and radiological approaches; however, it has later shifted toward an endoscopy-based approach. With the development of dedicated lumen-apposing metal stents (LAMS), interventional Endoscopic Ultrasound (EUS)-guided procedures have become the standard approach for PFC drainage. However, there is still limited consensus on several aspects of the multidisciplinary management of PFCs. The interventional endoscopy and ultrasound (i-EUS) group is an Italian network of clinicians and scientists with special interest in biliopancreatic interventional endoscopy, especially interventional EUS. This manuscript describes the first part of the results of a consensus conference organized by i-EUS with the aim of providing evidence-based guidance on aspects such as indications for treating PFCs, the timing of intervention, and different technical strategies for managing patients with PFCs.

Coaxial plastic stent placement within lumen-apposing metal stents for the management of pancreatic fluid collections: a systemic review and meta-analysis

BACKGROUND/AIMS

Coaxial placement of double pigtail plastic stents (DPPS) through lumen-apposing metal stents (LAMSs) is commonly performed to reduce the risk of LAMS obstruction, bleeding, and stent migration when used for the drainage of pancreatic fluid collections (PFCs). A systematic review and meta-analysis were performed to compare the outcomes of LAMS alone and LAMS with coaxial DPPS placement in the management of PFCs.

METHODS

A systematic review was conducted to identify studies comparing LAMS and LAMS/DPPS for PFC drainage. Primary outcomes included the rate of clinical success, overall adverse events (AEs), bleeding, infection, occlusion, and stent migration. The pooled effect size was summarized using a random-effects model and compared between LAMS and LAMS/DPPS by calculating odds ratios (ORs).

RESULTS

Nine studies involving 709 patients were identified (338 on LAMS and 371 on LAMS/DPPS). LAMS/DPPS was associated with a reduced risk of stent obstruction (OR, 0.59; p=0.004) and infection (OR, 0.55; p=0.001). No significant differences were observed in clinical success (OR, 0.96; p=0.440), overall AEs (OR, 0.57; p=0.060), bleeding (OR, 0.61; p=0.120), or stent migration (OR, 1.03; p=0.480).

CONCLUSIONS

Coaxial DPPS for LAMS drainage of PFCs is associated with a reduced risk of stent occlusion and infection; however, no difference was observed in the overall AE rates or bleeding.

WONDER-02: plastic stent vs. lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic pseudocysts-study protocol for a multicentre randomised non-inferiority trial

BACKGROUND

Endoscopic ultrasound (EUS)-guided transluminal drainage has become a first-line treatment modality for symptomatic pancreatic pseudocysts. Despite the increasing popularity of lumen-apposing metal stents (LAMSs), plastic stents may resolve non-necrotic fluid collections effectively with lower costs and no LAMS-specific adverse events. To date, there has been a paucity of data on the appropriate stent type in this setting. This trial aims to assess the non-inferiority of plastic stents to a LAMS for the initial EUS-guided drainage of pseudocysts.

METHODS

The WONDER-02 trial is a multicentre, open-label, non-inferiority, randomised controlled trial, which will enrol pancreatic pseudocyst patients requiring EUS-guided treatment in 26 centres in Japan. This trial plans to enrol 80 patients who will be randomised at a 1:1 ratio to receive either plastic stents or a LAMS (40 patients per arm). In the plastic stent group, EUS-guided drainage will be performed using two 7-Fr double pigtail stents. In the LAMS group, the treatment will be performed in the same way except for LAMS use. The step-up treatment will be performed via endoscopic and/or percutaneous procedures at the trial investigator's discretion. The primary endpoint is clinical success, which is defined as a decrease in a pseudocyst size to ≤ 2 cm and an improvement in inflammatory indicators (i.e. body temperature, white blood cell count, and serum C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, pseudocyst recurrence, and medical costs.

DISCUSSION

The WONDER-02 trial will investigate the efficacy and safety of plastic stents compared to a LAMS in EUS-guided treatment of symptomatic pancreatic pseudocysts with a particular focus on the non-inferior efficacy of plastic stents. The findings will help establish a new treatment algorithm for this population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06133023 registered on 9 November 2023. UMIN000052647 registered on 30 October 2023. jRCT1032230444 registered on 7 November 2023.

Consensus guidelines on the diagnosis and treatment of pancreatic pseudocyst and walled-off necrosis from a Chinese multiple disciplinary team expert panel

Objective

To prepare a set of practice guidelines to standardize the entire process, from diagnosis to treatment and follow-up, for pancreatic pseudocysts and walled-off necrosis.

Methods

Thirty-six experts in the fields of digestive endoscopy, pancreatic surgery, interventional radiology, and others presented their opinions via discussions in online conferences by referring to the patient, intervention, comparison, and outcomes principles and then reviewed the evidence and statements using the Delphi method to reach a consensus. The consensus of >80% was finally achieved for the items.

Results

The experts discussed and reached a consensus on 29 statements including 10 categories: (1) definition and classification, (2) imaging and endoscopic diagnosis, (3) therapeutic implications, (4) surgical therapy, (5) percutaneous catheter drainage, (6) endoscopic retrograde cholangiopancreatography, (7) EUS-guided drainage, (8) stent selection for EUS-guided drainage, (9) complication related to stents for cyst drainage, and (10) drug treatment and follow-up.

Conclusion

This consensus based on the clinical experience of experts in various fields and international evidence-based medicine further standardizes the multidisciplinary diagnosis and treatment processes for pancreatic pseudocysts and walled-off necrosis.

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.

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.

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.

Lumen-apposing metal stents with or without coaxial plastic stent placement for the management of pancreatic fluid collections

BACKGROUND AND AIMS

Coaxial double-pigtail plastic stent (DPPS) placement is often performed within lumen-apposing metal stents (LAMSs) for drainage of pancreatic fluid collections (PFCs) to prevent adverse events (AEs) such as stent occlusion and bleeding. This study compares the safety and outcomes of LAMSs alone versus LAMSs with coaxial DPPSs for PFC management.

METHODS

Patients undergoing drainage of a PFC with LAMSs were retrospectively identified and categorized as LAMS or LAMS/DPPS based on initial drainage strategy. The AE rate, AE type, and clinical success were extracted by chart review.

RESULTS

One hundred eighty-five individuals (83 LAMS, 102 LAMS/DPPS) were identified. No significant differences were found in rates of clinical success (75.9% LAMS vs 69.6% LAMS/DDPS, P = .34) or overall AEs (15.7% LAMS vs 15.7% LAMS/DPPS, P = .825).

CONCLUSIONS

In this comparative single-center study, placement of a coaxial DPPS for drainage of PFCs with LAMSs did not affect rates of AEs or clinical success.

[Transgastric necrectomy for acute pancreatitis]

The review is devoted to transgastric necrectomy in the treatment of infected forms of acute pancreatitis. The authors discuss the indications for transgastric necrectomy and technical features of these interventions (direct endoscopic necrectomy, laparoscopic and open transgastric necrectomy). Numerous studies devoted to results of transgastric necrectomy indicate advisability of this procedure in carefully selected patients and interdisciplinary interaction of various specialists before and after surgery. Regional specialized centers for the treatment of severe acute pancreatitis are necessary for wider introduction of minimally invasive surgical technologies and their personalization.

Endoscopic Necrosectomy

The management of walled-off necrosis has evolved substantially over the past 23 years since its first description. In this article, we review its history and the evidence supporting modern treatment, which is still subject to heterogeneity across centers and among endoscopists. This allows for creativity and customization of what can be an endoscopic marathon. Our typical practice is discussed with image and video guides aimed at improving procedure success.

Inverse association of hospital volume with in-hospital mortality rate of patients receiving EUS-guided interventions for pancreatic fluid collections

BACKGROUND AND AIMS

EUS-guided interventions currently serve as first-line treatment for symptomatic pancreatic fluid collections (PFCs) but require high-level expertise and multidisciplinary care. Hospital caseload has not been fully examined in relation to clinical outcomes of patients with endoscopically managed PFCs.

METHODS

Using the Diagnosis Procedure Combination database (a Japanese nationwide inpatient database), we identified 4053 patients receiving EUS-guided treatment of PFCs at 486 hospitals between 2010 and 2020 and examined an association of hospital volume (average annual number of cases at a hospital) with in-hospital mortality. Associations with bleeding, length of stay, and total costs were examined as secondary analyses. Multivariable logistic regression analysis was conducted with adjustment for potential confounders.

RESULTS

The hospital volume was inversely associated with the risk of in-hospital mortality (Ptrend < .001). The adjusted odds ratio for in-hospital mortality comparing the extreme quintiles of hospital volume was .17 (95% confidence interval, .09-.33). A restricted cubic spline analysis yielded no statistically significant evidence on the nonlinear relationship (Pnonlinearity = .19). The types of stents (plastic vs lumen-apposing metal stent) seemed to have no effect modification on the volume-mortality relationship (Pinteraction = .58). Higher hospital volume was also associated with lower risk of bleeding, shorter length of stay, and lower medical costs of inpatient care.

CONCLUSIONS

Higher hospital volume was associated with a lower risk of in-hospital mortality of patients receiving EUS-guided treatment of PFCs. A further investigation is warranted to justify the volume-based selective referral of the patients.

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.

Endoscopic ultrasound-guided versus percutaneous drainage for the management of post-operative fluid collections after distal pancreatectomy

BACKGROUND

Post-operative pancreatic fluid collections (POPFCs) can be drained using percutaneous or endoscopic approaches. The primary aim of this study was to compare rates of clinical success between endoscopic ultrasound-guided drainage (EUSD) with percutaneous drainage (PTD) in the management of symptomatic POPFCs after distal pancreatectomy. Secondary outcomes included technical success, total number of interventions, time to resolution, rates of adverse events (AEs), and POPFC recurrence.

METHODS

Adults who underwent distal pancreatectomy from January 2012 to August 2021 and developed symptomatic POPFC in the resection bed were retrospectively identified from a single academic center database. Demographic data, procedural data, and clinical outcomes were abstracted. Clinical success was defined as symptomatic improvement and radiographic resolution without requiring an alternate drainage modality. Quantitative variables were compared using a two-tailed t-test and categorical data were compared using Chi-squared or Fisher's exact tests.

RESULTS

Of 1046 patients that underwent distal pancreatectomy, 217 met study inclusion criteria (median age 60 years, 51.2% female), of whom 106 underwent EUSD and 111 PTD. There were no significant differences in baseline pathology and POPFC size. PTD was generally performed earlier after surgery (10 vs. 27 days; p < 0.001) and more commonly in the inpatient setting (82.9% vs. 49.1%; p < 0.001). EUSD was associated with a significantly higher rate of clinical success (92.5% vs. 76.6%; p = 0.001), fewer median number of interventions (2 vs. 4; p < 0.001), and lower rate of POPFC recurrence (7.6% vs. 20.7%; p = 0.007). AEs were similar between EUSD (10.4%) and PTD (6.3%, p = 0.28), with approximately one-third of EUSD AEs due to stent migration.

CONCLUSION

In patients with POPFCs after distal pancreatectomy, delayed drainage with EUSD was associated with higher rates of clinical success, fewer interventions, and lower rates of recurrence than earlier drainage with PTD.

Therapeutic Endoscopic Ultrasound: Current Indications and Future Perspectives

The transcendence of endoscopic ultrasound (EUS) from diagnostic to therapeutic tool has revolutionized management options in the field of gastroenterology. Through EUS-guided methods, pancreaticobiliary obstruction can now be utilized as an alternative to surgical and percutaneous approaches. This modality also allows for gallbladder drainage in patients who are not ideal operative candidates. By utilizing its unique imaging capabilities, EUS also allows for drainage access points in cases of gastric outlet obstruction as well as windows to ablate pancreatic cystic lesions. As technical progress continues to evolve, interventional gastroenterology continues to push the envelope of minimally invasive therapeutic procedures in a multidisciplinary setting. In this comprehensive review, we set out to describe current indications and innovations through EUS.

Endoscopic treatment of pancreatic necrosis: Still searching for perfection!

Over last few years, there has been a paradigm shift in the management of infected pancreatic necrosis with endoscopic and minimally invasive "step-up" management approach replacing open surgical necrosectomy. Because of being associated with reduced occurrence of new onset multi-organ failure, external pancreatic fistulae, shorter hospital stay, lower costs, and better quality of life compared with minimally invasive surgical approach, endoscopic "step-up" management approach is the preferred intervention for endoscopically accessible pancreatic necrotic collections at expert centers with endoscopic expertise. Development of lumen apposing metal stents and improvised accessories for interventional endoscopic ultrasound has revolutionized the endoscopic management of pancreatic necrosis making it more effective and safer. Despite these promising developments, endoscopic transluminal necrosectomy (ETN) remains the Achilles heel. Lack of dedicated endoscopic accessories, poor endoscopic visualization within the necrotic cavity, limited diameter of the instrument channel of the endoscope that is a significant impediment to remove large amount of necrotic material, and uncertain ability to avoid vessels and vital structures in the necrotic cavity are important limitations during endoscopic necrosectomy. Recent devices and solutions including use of cap assisted necrosectomy, over the scope grasper and powered endoscopic debridement device are welcome steps in our pursuit for an ideal, safer, and efficacious ETN device. This review will discuss recent advances as well as challenges in the endoscopic management of pancreatic necrosis.

Endoscopic ultrasound drainage of pancreatic fluid collections: do we know enough about the best approach?

Pancreatic fluid collection often occurs as a local complication of acute pancreatitis, and drainage is indicated in symptomatic patients. The drainage may be surgical, percutaneous, or endoscopic ultrasound (EUS) guided. In symptomatic collections older than 4 weeks and localized in the upper abdomen, EUS-guided drainage is the first choice of treatment. Lumen-apposing metal stents are useful in cases of walled-off necrosis, facilitating access to the cavity; however, they do not reduce the number of necrosectomy sessions required. In most pancreatic pseudocysts requiring drainage, plastic stents remain the first choice of treatment. This review aimed to summarize the principles and techniques of step-up therapy of pancreatic fluid collections, including preprocedural and postprocedural assessment and practical approaches of drainage and necrosectomy, making available evidence more accessible to endoscopists aiming to train for this procedure. Successful and safe EUS drainage connotes early recognition and treatment of complications and the presence of a multidisciplinary team for optimal patient management. However, the best time for necrosectomy, modality of drainage method (lumen-apposing metal stents or plastic stents), and duration of antibiotherapy are still under evaluation.

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.

The role of high serum triglyceride levels on pancreatic necrosis development and related complications

BACKGROUND

The relevance of elevated serum triglyceride (TG) levels in the early stages of acute pancreatitis (AP) not induced by hypertriglyceridemia (HTG) remains unclear. Our study aims to determine the role of elevated serum TG levels at admission in developing pancreatic necrosis.

METHODS

We analyzed the clinical data collected prospectively from patients with AP. According to TG levels measured in the first 24 h after admission, we stratified patients into four groups: Normal TG (< 150 mg/dL), Borderline-high TG (150-199 mg/dL), High TG (200-499 mg/dL) and Very high TG (≥ 500 mg/dL). We analyzed the association of TG levels and other risk factors with the development of pancreatic necrosis.

RESULTS

A total of 211 patients were included. In the Normal TG group: 122, in Borderline-high TG group: 38, in High TG group: 44, and in Very high TG group: 7. Pancreatic necrosis developed in 29.5% of the patients in the Normal TG group, 26.3% in the Borderline-high TG group, 52.3% in the High TG group, and 85.7% in the Very high TG group. The trend analysis observed a significant association between higher TG levels and pancreatic necrosis (p = 0.001). A multivariable analysis using logistic regression showed that elevated TG levels ≥ 200 mg/dL (High TG and Very high TG groups) were independently associated with pancreatic necrosis (OR: 3.27, 95% CI - 6.27, p < 0.001).

CONCLUSIONS

An elevated TG level at admission ≥ 200 mg/dl is independently associated with the development of pancreatic necrosis. The incidence of pancreatic necrosis increases proportionally with the severity of HTG.

Novel classification system for walled-off necrosis: a step toward standardized nomenclature and risk-stratification framework

BACKGROUND AND AIMS

The optimal therapeutic approach for walled-off necrosis (WON) is not fully understood, given the lack of a validated classification system. We propose a novel and robust classification system based on radiologic and clinical factors to standardize the nomenclature, provide a framework to guide comparative effectiveness trials, and inform the optimal WON interventional approach.

METHODS

This was a retrospective analysis of patients who underwent endoscopic management of WON by lumen-apposing metal stent placement at a tertiary referral center. Patients were classified according to the proposed QNI classification system: quadrant ("Q"), represented an abdominal quadrant distribution; necrosis ("N"), denoted by the percentage of necrosis of WON; and infection ("I"), denoted as positive blood culture and/or systemic inflammatory response syndrome reaction with a positive WON culture. Two blinded reviewers classified all patients according to the QNI system. Patients were then divided into 2 groups: those with a lower QNI stratification (≤2 quadrants and ≤30% necrosis; group 1) and those with a higher stratification (≥3 quadrants, 2 quadrants with ≥30% necrosis, or 1 quadrant with >60% necrosis and infection; group 2). The primary outcome was mean time to WON resolution. Secondary procedural and clinical outcomes between the groups were compared.

RESULTS

Seventy-one patients (75% men) were included and stratified by the QNI classification; group 1 comprised 17 patients and group 2, 54 patients. Patients in group 2 had a higher number of necrosectomies, longer hospital stays, and more readmissions. The mean time to resolution was longer in group 2 than in group 1 (79.6 ± 7.76 days vs 48.4 ± 9.22 days, P = .02). The mortality rate was higher in group 2 (15% vs 0%, P = .18).

CONCLUSIONS

Despite the heterogeneous nature of WON in severe acute pancreatitis, a proposed QNI system may provide a standardized framework for WON classification to inform clinical trials, risk-stratify the disease course, and potentially inform an optimal management approach.

Endoscopic step up: When and how

The management of (peri)pancreatic collections has undergone a paradigm shift from open surgical drainage to minimally invasive endoscopic, percutaneous, or surgical interventions. Minimally invasive interventions are associated with less morbidity and mortality compared to open necrosectomy. The (peri)pancreatic collections are currently treated with a “step-up approach” of an initial drainage procedure followed, if necessary, by a more invasive debridement. The step-up approach for management of (peri)pancreatic collections is mainly of two types, namely, surgical and endoscopic. Surgical step up includes initial image-guided percutaneous catheter drainage followed, if necessary, by minimally invasive video-assisted retroperitoneal debridement. Endoscopic step-up approach includes endoscopic transluminal drainage followed, if necessary by direct endoscopic necrosectomy. The development of endoscopic ultrasound and lumen apposing metal stents (LAMSs) has revolutionized the endoscopic management of (peri)pancreatic collections. Compared to surgical step-up approach, endoscopic step-up treatment approach has been reported to be associated with less new-onset organ failure, pancreatic fistula, enterocutaneous fistula, or perforation of visceral organ and shorter hospital/intensive care unit stay. This review will mainly focus on indications, techniques, timing, and recent advances related to endoscopic step-up approach in management of symptomatic(peri)pancreatic collections.

Disconnected pancreatic duct syndrome and outcomes of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Systematic review and meta-analysis

BACKGROUND

Disconnected pancreatic duct syndrome (DPDS) frequently occurs in patients with acute necrotizing pancreatitis and resultant pancreatic fluid collection (PFC). We performed a systematic review and meta-analysis to evaluate outcomes of endoscopic ultrasound-guided treatment of PFCs according to the presence of DPDS.

METHODS

Using PubMed, Embase, and the Cochrane database, we identified clinical studies published until January 2021 with data comparing outcomes of endoscopic ultrasound-guided drainage of PFCs between DPDS and non-DPDS patients. We pooled data on technical and clinical success rates, PFC recurrence, and adverse events using the random-effects model.

RESULTS

We identified five eligible articles including 941 PFC patients treated with endoscopic ultrasound-guided interventions. Clinical success, defined as resolution of the PFC and symptoms, was achieved in a majority of the cases irrespective of DPDS (pooled odds ratio [OR] comparing DPDS to non-DPDS patients, 0.77; 95% confidence interval [CI] 0.33-1.81). Compared to patients without DPDS, patients with DPDS were more likely to undergo PFC recurrence (pooled OR 6.72; 95% CI 2.72-16.6) after clinical resolution of PFC. Prolonged plastic stent placement following the clinical resolution was more frequently performed in DPDS patients than in non-DPDS patients (pooled OR 15.9; 95% CI 2.76-91.9). No statistically significant difference was observed between the groups in terms of the rate of technical success, adverse events, or mortality.

CONCLUSION

Disconnected pancreatic duct syndrome was associated with higher rate of PFC recurrence after successful endoscopic treatment of PFCs. Future studies should evaluate effectiveness and optimal duration of long-term placement of transmural plastic stents for PFCs with DPDS.