Plastic stents are more cost-effective than lumen-apposing metal stents in management of pancreatic pseudocysts

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.

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 management of pancreatic walled-off necrosis

Pancreatic walled-off necrosis (WON) is a complication of severe pancreatitis. Endoscopic transmural drainage has been recognized as the first-line treatment for pancreatic fluid collections. Endoscopy offers a minimally invasive approach when compared to surgical drainage. Today, endoscopists may choose to use self-expanding metal stents, pigtail stents, or lumen-apposing metal stents to facilitate drainage of fluid collections. Current data suggest that all 3 approaches yield similar outcomes. It was previously thought that drainage should be performed 4 weeks from the initial event of pancreatitis, theoretically allowing the capsule to mature. However, current data show that both early (<4 weeks) and standard (≥4 weeks) endoscopic drainage are comparable. Herein, we provide an up-to-date state-of-the-art review of the indications, techniques, innovations, outcomes, and future perspectives following drainage of pancreatic WON.

Long-term transmural drainage of pancreatic fluid collections with double pigtail stents following lumen-apposing metal stent placement improves recurrence-free survival in disconnected pancreatic duct syndrome

OBJECTIVES

Disconnected pancreatic duct syndrome (DPDS) is the most common cause of pancreatic fluid collection (PFC) recurrence. While long-term transmural drainage with plastic stents is the preferred endoscopic approach, there is a paucity of literature on patients undergoing initial drainage with lumen-apposing metal stents (LAMS). We describe our experience managing patients with DPDS.

METHODS

A retrospective review of a prospectively maintained database (November 2015-September 2020) was performed looking at clinical outcomes and overall survival for patients undergoing endoscopic management of PFCs using LAMS. The primary outcome was to assess recurrence-free survival in PFC patients with DPDS managed with or without double pigtail stents (DPS) replacement after LAMS removal.

RESULTS

Of 96 patients with PFCs, 48 with DPDS were included in the study. The median follow-up was 20.1 months. LAMS replacement with DPS was successful in 21/48 (43.8%) patients. Recurrence was seen in 1/21 (5%) patients with DPS replacement and 10/27 (37%) without DPS replacement. In multivariable models, a longer duration of LAMS placement was negatively associated with successful DPS replacement (odds ratio 1.33, 95% confidence interval [CI] 1.11, 1.59, P = 0.0019) and successful LAMS replacement with DPS in patients with DPDS improved recurrence-free survival (hazard ratio 0.09, 95% CI 0.01, 0.83, P = 0.033).

CONCLUSION

In patients with PFCs and DPDS, early replacement of LAMS with DPS improves the likelihood of successful long-term transmural drainage and decreases recurrences.

Diagnostic and Therapeutic Indications for Endoscopic Ultrasound (EUS) in Patients with Pancreatic and Biliary Disease—Novel Interventional Procedures

There is growing evidence supporting the substantial, essential and indispensable role of endoscopic ultrasound (EUS) as a key diagnostic armamentarium for upper GI oncologic surgery. Well described in countless publications, EUS holds that position in gastroenterological expert centers all over Europe. Despite its undisputable contributions to oncologic upper GI surgery, the availability of this technique at the expert level shows up in an irregular spread pattern. Endoscopic ultrasound’s primary use during the first few years after its creation was the detection of pancreatic cancer. From then on, EUS developed in different directions, becoming a diagnostic tool that increasingly better defines its status as a method of minimally invasive therapeutic applications and a useful addition to surgical options. As a result, several surgical interventions could even be replaced by ultrasound-targeted interventions. This process took place in just a few years and was made possible by technical development that sensibly combined high-resolution ultrasound with therapeutic endoscopy. The present article will serve to cover the most prevalent uses with supporting data considering the growing list of suggested indications for EUS while also examining cutting-edge initiatives that might soon become the standard of clinical practice. Endoscopic centers with high expertise are needed to train future experts in the growing field of EUS interventions.

Novel 15-mm-long lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic fluid collections located ≥10 mm from the luminal wall

BACKGROUND

Endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) by cautery-enhanced lumen-apposing metal stents (LAMS) has largely been limited to collections located < 10 mm from the luminal wall. We present outcomes of the use of a novel 15-mm-long cautery-enhanced LAMS for drainage of PFCs located ≥ 10 mm away.

METHODS

This international, multicenter study analyzed all adults with PFCs located ≥ 10 mm from the luminal wall who were treated by EUS-guided drainage using the 15-mm-long cautery-enhanced LAMS. The primary outcome was technical success. Secondary outcomes included clinical success (decrease in PFC size by ≥ 50 % at 30 days and resolution of clinical symptoms without surgical intervention), complications, and recurrence.

RESULTS

35 patients (median age 57 years; interquartile range [IQR] 47-64 years; 49 % male) underwent novel LAMS placement for drainage of PFCs (26 walled-off necrosis, 9 pseudocysts), measuring 85 mm (IQR 64-117) maximal diameter and located 11.8 mm (IQR 10-12.3; range 10-14) from the gastric/duodenal wall. Technical and clinical success were high (both 97 %), with recurrence in one patient (3 %) at a median follow-up of 123 days (58-236). Three complications occurred (9 %; one mild, two moderate).

CONCLUSIONS

The 15-mm-long cautery-enhanced LAMS was feasible and safe for drainage of PFCs located 10-14 mm from the luminal wall.

Lumen Apposition: A Changing Landscape in Therapeutic Endoscopy

The concept of endoscopic lumen apposition has seen a dramatic shift in the last several decades. Early natural orifice trans-luminal endoscopic surgery (NOTES) concepts have transformed into specialized lumen-apposing metal stents (LAMSs) and delivery devices, which provide endoscopists a minimally invasive alternative to surgical intervention. These LAMSs have become the bedrock of therapeutic endoscopy and provide treatment for a wide spectrum of gastrointestinal disorders. In this review, we summarize the changing landscape of therapeutic endoscopy by highlighting the use of LAMS and future directions as well as alternative devices to achieve lumen apposition.

Lumen Apposition: A Changing Landscape in Therapeutic Endoscopy

The concept of endoscopic lumen apposition has seen a dramatic shift in the last several decades. Early natural orifice trans-luminal endoscopic surgery (NOTES) concepts have transformed into specialized lumen-apposing metal stents (LAMSs) and delivery devices, which provide endoscopists a minimally invasive alternative to surgical intervention. These LAMSs have become the bedrock of therapeutic endoscopy and provide treatment for a wide spectrum of gastrointestinal disorders. In this review, we summarize the changing landscape of therapeutic endoscopy by highlighting the use of LAMS and future directions as well as alternative devices to achieve lumen apposition.

Management of pancreatic fluid collections

Pancreatic fluid collections often develop as a complication of acute pancreatitis but can be seen in a variety of conditions including chronic pancreatitis, trauma, malignancy or post-operatively. It is important to classify a pancreatic fluid collection in order to optimize treatment strategies and management. Most interventions are targeted towards the management of delayed complications of pancreatitis, including pancreatic pseudocysts and walled-off necrosis (WON), which often develop days to weeks after the initial episode of pancreatitis. Surgical, percutaneous, and endoscopic interventions are all possible methods for treatment of pancreatic fluid collections, however endoscopic drainage with endoscopic ultrasound has become first-line. Advances within endoscopic drainage strategies have also led to innovative changes in the specific stents used for treatment, with possible options including double pigtail plastic stents, fully covered self-expanding metal stents and lumen-apposing metal stents (LAMS).

Endotherapy in Pancreatic Diseases

Interventional endoscopy is now considered an effective minimally invasive treatment modality for the management of pancreatic diseases. It is important for the clinician to know the indications and contraindications as well as the timing of various endoscopic interventions. This will help in its safe and effective use and consequently decrease morbidity and mortality from various pancreatic diseases. This review will provide a broad overview of the indications, techniques, and outcomes of pancreatic endotherapy.

Efficacy and safety of endoscopic drainage of peripancreatic fluid collections: a retrospective multicenter European study

BACKGROUND

Endoscopic ultrasound (EUS)-guided transmural drainage allows treatment of symptomatic peripancreatic fluid collections (PFCs), with lumen-apposing metal stents (LAMS) and double pigtail plastic stents (DPPS) being the 2 most frequently used modalities.

METHODS

Consecutive patients undergoing PFC drainage in 10 European centers were retrospectively retrieved. Technical success (successful deployment), clinical success (satisfactory drainage), rate and type of early adverse events, drainage duration and complications on stent removal were evaluated.

RESULTS

A total of 128 patients-92 men (71.9%), age 57.2±11.9 years-underwent drainage, with pancreatic pseudocyst (PC) and walled-off necrosis (WON) in 92 (71.9%) and 36 (28.1%) patients, respectively. LAMS were used in 80 (62.5%) patients and DPPS in 48 (37.5%). Technical success was achieved in 124 (96.9%) of the cases, with no difference regarding either the type of stent (P>0.99) or PFC type (P=0.07). Clinical success was achieved in 119 (93%); PC had a better response than WON (91/92 vs. 28/36, P<0.001), but the type of stent did not affect the clinical success rate (P=0.29). Twenty patients (15.6%) had at least one early complication, with bleeding being the most common (n=7/20, 35%). No difference was detected in complication rate per type of stent (P=0.61) or per PFC type (P=0.1). Drainage duration was significantly longer with DPPS compared to LAMS: 88 (70-112) vs. 35 (29-55.3) days, P<0.001.

CONCLUSIONS

EUS-guided drainage of PFCs achieves high percentages of technical and clinical success. Drainage using LAMS is of shorter duration, but the complication rate is similar between the 2 modalities.

Evidence-based clinical practice guidelines for chronic pancreatitis 2021

BACKGROUND

Chronic pancreatitis (CP) is defined according to the recently proposed mechanistic definition as a pathological fibro-inflammatory syndrome of the pancreas in individuals with genetic, environmental, and/or other risk factors who develop persistent pathological responses to parenchymal injury or stress.

METHODS

The clinical practice guidelines for CP in Japan were revised in 2021 based on the 2019 Japanese clinical diagnostic criteria for CP, which incorporate the concept of a pathogenic fibro-inflammatory syndrome in the pancreas. In this third edition, clinical questions are reclassified into clinical questions, background questions, and future research questions.

RESULTS

Based on analysis of newly accumulated evidence, the strength of evidence and recommendations for each clinical question is described in terms of treatment selection, lifestyle guidance, pain control, treatment of exocrine and endocrine insufficiency, and treatment of complications. A flowchart outlining indications, treatment selection, and policies for cases in which treatment is ineffective is provided. For pain control, pharmacological treatment and the indications and timing for endoscopic and surgical treatment have been updated in the revised edition.

CONCLUSIONS

These updated guidelines provide clinicians with useful information to assist in the diagnosis and treatment of CP.

Lumen-apposing metal stents (with videos)

BACKGROUND AND AIMS

Lumen-apposing metal stents (LAMSs) are a novel class of devices that have expanded the spectrum of endoscopic GI interventions. LAMSs with their dumbbell configuration, short saddle length, and large inner luminal diameter provide favorable stent characteristics to facilitate anastomosis formation between the gut lumen and adjacent structures.

METHODS

The MEDLINE database was searched through April 2021 for articles related to LAMSs by using additional relevant keywords such as "walled-off pancreatic necrosis," "pseudocysts," "pancreatic fluid collection," "cholecystitis," "gastroenterostomy," in addition to "endoscopic treatment" and "endoscopic management," among others.

RESULTS

This technology review describes the full spectrum of LAMS designs and delivery systems, techniques for deployment, procedural outcomes, safety, training issues, and financial considerations.

CONCLUSIONS

Although LAMSs were initially introduced for drainage of pancreatic pseudocysts and walled-off necrosis, the versatility of these devices has led to a variety of off-label uses including gallbladder drainage, enteric bypass with the creation of gastroenterostomies, and treatment of luminal GI strictures.

Comparative Effectiveness of Lumen-Apposing Metal Stents and Plastic Stents for the Treatment of Pancreatic Walled-Off Necrosis: A Meta-analysis

Background

Plastic stents (PS), lumen-apposing metal stents (LAMS) and biflanged metal stents (BFMS) are used for initial drainage of pancreatic walled-off necrosis (WON). There are no strong evidence to support the use of LAMS/BFMS over PS, and prior systematic reviews lack comparative analyses and also lack both trial data and observational studies for WON efficacy outcomes. The aim of this study is to compare the efficacy and adverse events (AEs) in LAMS/BFMS versus PS in patients with pancreatic WON.

Methods

A comprehensive search up to December 1, 2020, was performed. The primary outcome was clinical improvement after drainage. Secondary outcomes included AEs and technical failure. Pooled odds ratios (OR) with 95% confidence intervals (CI) were reported using random effects models. Heterogeneity was evaluated with the Cochrane I  2 statistic. Subgroup and sensitivity analyses were performed. The quality of the evidence was assessed using Grading of Recommendations, Assessment, Development and Evaluations (GRADE).

Results

Nine studies (one randomized controlled trial and eight observational) were included for the primary outcome including 493 patients treated with LAMS/BFMS and 514 with PS. LAMS/BFMS were associated with higher odds of clinical improvement compared with PS (OR 2.58; 95% CI 1.81, 3.68; I  2 = 1%). This association remained robust in sensitivity analyses. The use of LAMS/BFMS was not associated with higher AEs (OR 1.22; 0.61, 2.46; I2 = 71%). There was no difference in technical failure (OR 1.06; 0.19, 6.00; I2 = 12%).

Conclusions

LAMS/BFMS seem to result in better clinical outcomes compared with PS in patients with pancreatic WON, with comparable AEs and technical failure. Larger randomized controlled trials for this comparison are warranted.

Early cholangioscopy-assisted electrohydraulic lithotripsy in difficult biliary stones is cost-effective

BACKGROUND AND AIMS

Single-operator cholangioscopy-assisted electrohydraulic lithotripsy (SOC-EHL) is effective and safe in difficult choledocholithiasis. The optimal timing of SOC-EHL use, however, in refractory stones has not been elucidated. The following aims to determine the most cost-effective timing of SOC-EHL introduction in the management of choledocholithiasis.

METHODS

A cost-effectiveness model was developed assessing three strategies with a progressively delayed introduction of SOC-EHL. Probability estimates of patient pathways were obtained from a systematic review. The unit of effectiveness is complete ductal clearance without need for surgery. Cost is expressed in 2018 US dollars and stem from outpatient US databases.

RESULTS

The three strategies achieved comparable ductal clearance rates ranging from 97.3% to 99.7%. The least expensive strategy is to perform SOC-EHL during the first endoscopic retrograde cholangiography pancreatography (ERCP) (SOC-1: 18,506$). The strategy of postponing the use of SOC-EHL to the third ERCP (SOC-3) is more expensive (US$18,895) but is 2% more effective. (0.9967). SOC-EHL during the second ERCP in the model (SOC-2) is the least cost-effective. Sensitivity analyses show altered conclusions according to the cost of SOC-EHL, effectiveness of conventional ERCP, and altered willingness-to-pay (WTP) thresholds with early SOC-1 being the most optimal approach below a WTP cut-off of US$20,295.

CONCLUSIONS

Early utilization of SOC-EHL (SOC-1) in difficult choledocholithiasis may be the least costly strategy with an effectiveness approximating those achieved with a delayed approach where one or more conventional ERCP(s) are reattempted prior to SOC-EHL introduction.

Therapeutic interventional endoscopic ultrasound in pancreato-biliary disorders: Does it really replace the surgical/percutaneous approach?

Pancreato-biliary disorders are still incredibly challenging in the field of gastroenterology, as they would sometimes require multi-approach interventional procedures. Recently, therapeutic interventional endoscopic ultrasound (EUS) has emerged as a potential alternative to surgical or percutaneous approaches. Unfortunately, considering the high cost of EUS, lack of facility and expertise, most gastroenterologists still often refer cases to undergo surgical interventions without contemplating the possibility of utilizing EUS first. EUS-guided biliary drainage has become one of the best choices for establishing access to biliary system, given the clear visualization of pancreas, gallbladder, and common bile duct. Although there are still only a few studies which directly compare EUS-guided and surgical approaches for biliary drainage, current evidence demonstrated the superiority of EUS-guided approach in terms of adverse events and re-intervention rates, with similarly high technical and clinical success rates compared to percutaneous and surgical approaches, especially in patients with history of failed endoscopic retrograde cholangiopancreatography attempt. Comparable success rates with shorter length of hospital stay between endoscopic and surgical approaches have also been exhibited for pancreatic pseudocysts and walled-off necrosis. Recent findings about the progress of EUS approach in gastroenterostomy/jejunostomy also indicated a promising potential of EUS, as a less invasive approach, for managing gastric outlet obstruction.

The Use of Decision Analytic Modeling in the Evaluation of Surgical Innovations: A Scoping Review

OBJECTIVES

The main objective of this review was to map how decision analytic models are used in surgical innovation (in which research phase, with what aim) and to understand how challenges related to the assessment of surgical interventions are incorporated.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library for studies published in 2018. We included original articles using a decision analytic model to compare surgical strategies. We included modeling studies of surgical innovations. General, innovation, and modeling characteristics were extracted, as were outcomes, recommendations, and handling of challenges related to the assessment of surgical interventions (learning curve, incremental innovation, dynamic pricing, quality variation, organizational impact).

RESULTS

We included 46 studies. The number of studies increased with each research phase, from 4% (n = 2) in the preclinical phase to 40% (n = 20) in phase 3 studies. Eighty-one studies were excluded because they investigated established surgical procedures, indicating that modeling is predominantly applied after the innovation process. Regardless of the research stage, the aim to determine cost-effectiveness was most frequently identified (n = 40, 87%), whereas exploratory aims (eg, exploring when a strategy becomes cost-effective) were less common (n = 9, 20%). Most challenges related to the assessment of surgical interventions were rarely incorporated in models (eg, learning curve [n = 1, 2%], organizational impact [n = 2, 4%], and incremental innovation [n = 1, 2%]), except for dynamic pricing (n = 10, 22%) and quality variation (n = 6, 13%).

CONCLUSIONS

In surgical innovation, modeling is predominantly used in later research stages to assess cost-effectiveness. The exploratory use of modeling seems still largely overlooked in surgery; therefore, the opportunity to inform research and development may not be optimally used.

Endoscopic Management of Pancreatic Fluid Collections

Pancreatic fluid collections (PFCs) are a common sequela of pancreatitis. Most PFCs can be managed conservatively, but symptomatic PFCs require either surgical, percutaneous, or endoscopic intervention. Recent advances in the therapeutics of PFCs, including the step-up approach, endoscopic ultrasound-guided transmural drainage with lumen apposing metal stents, and direct endoscopic necrosectomy, have ushered endoscopy to the forefront of PFCs management and have allowed for improved patient outcomes and decreased morbidity. In this review, we explore the progress and future of endoscopic management of PFCs.

Peripancreatic fluid collections, plastic stents, and different sub-types of metal stents: Where does the evidence land?

BACKGROUND

Peripancreatic fluid collections (PFCs) are a frequent complication of acute pancreatitis. Symptomatic PFCs may need to be drained, and there are multiple endoscopic accessories that can facilitate the procedure. This paper aims to compare the success rate, number of procedures required for resolution and adverse events rate for PFCs EUS-guided drainage with plastic stents and lumen-apposing metal stents (LAMS).

METHODS

This is a retrospective analysis of a consecutive sample of patients that was collected from 2013 - 2019. The medical records of these patients were reviewed, and the outcomes for each type of stent (plastic vs LAMS, and different subtypes of LAMS) were compared in terms of clinical success, number of re-interventions needed, and adverse events.

RESULTS

A total of 33 patients (23 males) were treated for PFCs with EUS-guided drainage and stenting. The patients' ages ranged between 14 and 85 years (mean ± SD: 43.5 ± 19 years). Overall, there was no difference between plastic stents and LAMS in terms of symptomatic recovery (P = 0. 24), but metal stents had better results with regards to radiological resolution (P = 0.03), and were associated with a higher number of necrosectomies (P = 0.029). Adverse events occurred more frequently in patients who had plastic stents, but direct comparison between the two groups showed that the difference was not statistically significant (P = 0.2). Stratification for different LAMS subtypes showed no difference in terms of symptomatic or radiological resolution (P =0.49), number of rescue procedures (P = 0.41), and adverse events (P = 0.81).

CONCLUSION

Our study, along with the current available evidence, suggests a slight advantage of metal stents over plastic stents in terms of clinical success, need for rescue procedures, and incidence of adverse events. Furthermore, it provides empirical evidence that the different sub-types of LAMS perform similarly when compared against each other.

Advances in Interventional Endoscopic Ultrasound (EUS): A Technical Review

Endoscopic ultrasound (EUS) has become the therapeutic intervention of choice for multiple diseases and continues to evolve rapidly. Its increasing use has allowed the development and adaptation of multiple, revolutionary devices and tools. Currently, there is paucity of randomized clinical trials evaluating multiple EUS-guided interventions and the vast majority of published data is heterogenous. However, the available literature on EUS-guided therapeutic interventions continues to expand and demonstrate its safety, efficacy and cost effectiveness in carefully selected patients when performed by expert endosonographers. The future of interventional EUS appears to be bright!

Performance Characteristics of a Lumen-Apposing Metal Stent for Pancreatic Fluid Collections: A Prospective Cohort Study

Background

Endoscopic ultrasound-guided transmural drainage is the preferred management of pancreatic fluid collections (PFCs). Optimizing drainage is important and there remains debate as to the choice of stent. A recent trend towards the use of lumen-apposing metal stents (LAMS) has emerged.

Aim

To evaluate the performance characteristics of a LAMS based on a prospective protocol (CT scan 1 week after placement to assess for resolution and need for necrosectomy followed by stent removal within 3 weeks).

Methods

This is a descriptive prospective cohort study performed at a single centre. The primary outcome was clinical success. Secondary outcomes were technical success, procedure time, total number of endoscopic procedures with or without necrosectomy, stent indwell time, stent functionality and adverse events.

Results

Thirty-seven patients (21 males, mean age 46.5 years) underwent placement of LAMS for 41 PFCs (median size 12 cm). There were 18 pseudocysts and 23 walled-off necrosis. Clinical success was seen in 33 of 41 (80%) PFCs. Of the remaining eight patients, six underwent surgery and two patients died from underlying malignant disease (although their PFC had completely resolved). Technical success and stent functionality were 100%. The median procedure time was 14 min (interquartile range 11 min to 20 min). Of the 23 walled-off necrosis, 9 (39%) required necrosectomy. The median stent indwell time was 19 days (interquartile range 14 to 22 days). There were no serious adverse events.

Conclusions

Our protocol demonstrates excellent performance characteristics of LAMS. Their clinical efficacy and favourable safety profile suggest that they may be the preferred modality for endoscopic ultrasound-guided management of PFCs.

Are Lumen-Apposing Metal Stents More Effective Than Plastic Stents for the Management of Pancreatic Fluid Collections: An Updated Systematic Review and Meta-analysis

Background and Aims

Recently, a new type of metal stent, named lumen-apposing metal stents (LAMS), has been designed to manage pancreatic fluid collections (PFC), and a few studies have reported its efficacy and safety. Therefore, we conducted this meta-analysis to investigate the role of LAMS for PFC.

Methods

We searched the studies from PubMed, MEDLINE, Embase, and Cochrane databases from inception to May 2019. We extracted the data and analyzed the technical success, clinical success, and adverse events of LAMS to evaluate its efficacy and safety.

Results

Twenty studies with 1534 patients were included. The pooled technical success, clinical success, and adverse event rates of LAMS for PFC were 96.2% (95% confidence interval (CI): 94.6%-97.4%), 86.8% (95% CI: 83.1%-89.8%), and 20.7% (95% CI: 16.1%-26.1%), respectively. Eight studies including 875 patients compared the clinical outcomes of LAMS with plastic stents. The pooled risk ratio (RR) of technical success and clinical success for LAMS and plastic stent was 1.01 (95% CI: 0.98-1.04, P = 0.62) and 1.06 (95% CI: 1.01-1.12, P = 0.03), respectively. As for the overall adverse events, the pooled RR was 1.51 (95% CI: 0.67-3.44, P = 0.32).

Conclusions

Our current study revealed that LAMS has advantages over plastic stents for PFC, with higher clinical success rate and lower complication rate of infection and occlusion.

Recent advances in treatment of pancreatic pseudocyst with endoscopic ultrasonography guided lumen-apposing metal stents

Endoscopic pancreatic pseudocyst (PPC) drainage has become one of the most important methods for the treatment of PPC. With the continuous application of the new lumen-apposing metal stent (LAMS), it has shown better efficacy and clinical practical value. This paper focuses on the current situation of endoscopic PPC drainage, especially the therapeutic effect, complications, and countermeasures with endoscopic ultrasound-guided LAMS.

Prospective multicenter international study on the outcomes of a newly developed self-approximating lumen-apposing metallic stent for drainage of pancreatic fluid collections and endoscopic necrosectomy

BACKGROUND

A novel self-approximating lumen-apposing metallic stent (LAMS; Niti-S Spaxus, Taewoong Medical, Gyeonggi-do, Korea) has recently become available. The aim of the present study was to evaluate the outcomes for drainage of pancreatic fluid collections (PFC).

METHODS

This was a prospective international multicentered study conducted in six high-volume institutions across Asia. Consecutive patients suffering from pancreatic pseudocyst or walled-off pancreatic necrosis (WOPN) requiring endoscopic ultrasonography-guided drainage were recruited. Outcomes included technical and clinical success, adverse events, procedural events, interventions through the stent and recurrence rates.

RESULTS

Between August 2016 and November 2017, 59 patients were recruited to this study. Thirty-nine patients (66.1%) had WOPN and mean (SD) size of PFC was 11.5 (5.1) cm. Technical and clinical success rates were 100%. Mean (SD) procedural time was 35.0 (17.2) minutes. Sixteen-millimeter stents were used in 66.1% of the patients. Fifty-four sessions of necrosectomy were carried out with the stent in situ in 17 patients. Stent-related adverse event (AE) rate was 6.8%. Three patients (5.1%) suffered from bleeding after stenting and one required angiographic embolization. Two patients (3.4%) suffered from recurrence during a mean (SD) follow-up time of 325.6 (355.5) days. There were no differences in outcomes between those with pseudocysts or WOPN except for the duration of hospital stay (P = 0.012).

CONCLUSION

Use of a self-approximating LAMS for drainage of PFC was safe and effective. Endoscopic necrosectomy could be carried out through the stent with ease. The device was associated with a low rate of stent-related AE.

Lumen-apposing metal stents for endoscopic ultrasonography-guided interventions

Lumen-apposing metal stents (LAMS) are integrated in a single-step delivery platform and can be deployed under endoscopic ultrasound-guidance for the drainage of intra-abdominal fluid collections, decompression of obstructed ductal systems, establishment of anastomosis or creation of fistulous tracts between organs that can facilitate further endoscopic interventions if required. A unique feature of LAMS is their ability to approximate the adjoining structures, thereby minimizing the potential for leak and perforation. Consequently, the innovation has advanced our ability to carry out complex therapeutic interventions and obviate the need for high-risk surgical procedures, particularly in morbid patients. However, a keen awareness of the technical design of LAMS and its implication on treatment effect is important to minimize adverse events and to improve clinical outcomes. This review outlines the technical approach to placement of LAMS, procedural challenges, adverse events, current clinical indications and emerging applications.

Therapeutic EUS: New tools, new devices, new applications

Linear echoendoscopes with large instrument channels enable EUS-guided interventions in organs and anatomical spaces in proximity to the gastrointestinal tract. Novel devices and tools designed for EUS-guided transluminal interventions allow various new applications and improve the efficacy and safety of these procedures. New-generation biopsy needles provide higher histology rates and require less passes. Specially designed stents and stent insertion devices enable intra- and extra-hepatic bile and pancreatic duct stenting as well as gallbladder drainage. Currently, EUS-guided biliary drainage in obstructive jaundice due to malignant distal bile duct obstruction is feasible and safe when ERCP has failed. It might replace ERCP as first choice intervention in future. EUS-guided transmural stenting is regarded as the preferred intervention in the management of symptomatic peripancreatic fluid collections. Creating a new anastomosis between different organs such as gastrojejunostomy has also become possible with lumen-apposing stents. EUS-guided creation of a gastrogastrostomy is a promising novel technique to access the excluded stomach to facilitate conventional ERCP in patients with Roux-en-Y gastric bypass anatomy. The role of EUS in tumor ablation and targeted angiotherapy is also constantly expanding. In this review, we report on the newest developments of therapeutic EUS within the past 4 years.