Endoscopic ultrasound-guided placement of plastic vs. biflanged metal stents for therapy of walled-off necrosis: a retrospective single-center series

Comparative Efficacy and Safety of Different Stent Types for Pancreatic Fluid Collections: A Systematic Review and Network Meta-Analysis

BACKGROUND AND AIMS

Drainage of pancreatic fluid collections (PFCs) is required in select cases including infected or symptomatic collections. In this network meta-analysis, we have compared lumen-apposing metal stents (LAMS), fully covered self-expandable metal stents (FCSEMS), and double-pigtail stents (DPS) to identify the most useful stent type in the management of PFCs.

METHODS

We reviewed several databases to identify studies that compared DPS or FCSEMS with LAMS and the ones which compared DPS with FCSEMS for the treatment of PFCs. Our outcomes of interest were clinical success, adverse events, technical success, recurrence of PFCs, and procedure duration. Random effects model and frequentist approach were used for statistical analysis.

RESULTS

We included 28 studies with 2974 patients. Rate of clinical success was significantly lower with DPS compared to LAMS, OR (95% CI): 0.43 (0.32, 0.59). Rate of recurrence was higher with DPS compared to LAMS, OR (95% CI): 2.06 (1.19, 3.57). We found no significant difference in rate of adverse events between groups. Rate of technical success was higher for FCSEMS compared to LAMS. Procedure duration was significantly shorter for LAMS compared to DPS and FCSEMS. Based on frequentist approach, LAMS was found to be superior to DPS and FCSEMS in achieving higher clinical success, lower rate of adverse events and recurrence, and shorter procedure time.

CONCLUSIONS

This network meta-analysis demonstrates the superiority of LAMS over DPS and FCSEMS in the management of PFCs in achieving a higher clinical success, shorter procedure time, and lower rate of recurrence. Some of the analyses are not adequately powered to make firm conclusions, and future large multicenter RCTs are required to further evaluate this issue.

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.

Tardive Peritonitis After Endoscopic Ultrasound-Guided Pancreatic Pseudocyst Drainage: A Case Report

Here, we report a case of tardive peritonitis after endoscopic ultrasound (EUS)-guided transmural pancreatic pseudocyst drainage. A 50-year-old man was diagnosed with acute pancreatitis and a pancreatic pseudocyst measuring 5 cm. Ten months later, his pancreatic pseudocyst was 10 cm. We performed EUS-guided transmural drainage using a lumen-apposing metal stent. After two months, the stent was replaced with a double-pigtail plastic stent. Two months later, the patient developed fever and abdominal pain, and computed tomography revealed abdominal free air. He was diagnosed with peritonitis due to free air caused by a fistula rupture. The double-pigtail plastic stent was removed, and clipping was performed at the fistula site to achieve closure. The patient's symptoms subsequently improved. Long-term placement of a plastic stent for pancreatic pseudocysts makes recurrence less likely, but late adverse events due to stent placement can occur. Notably, fistula rupture can occur even when the fistula is well-formed several months after the initial drainage.

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.

Risk of recurrence with or without plastic stent after EUS-guided treatment of peripancreatic fluid collections: A systematic review and meta-analysis

Background and study aims Recent advances in endoscopic transmural treatment have improved the clinical outcomes of patients with pancreatic fluid collections (PFCs). However, there is still a debate about the preventive effect of long-term placement of a transmural plastic stent (PS) on recurrence after successful endoscopic ultrasound (EUS)-guided treatment of PFCs. We conducted a systematic review and meta-analysis to evaluate PFC recurrence rates with and without a transmural PS after EUS-guided treatment. Patients and methods A systematic literature search of PubMed, Embase, and the Cochrane database was conducted to identify clinical studies comparing outcomes with and without transmural PS published until September 2022. Data on PFC recurrence and adverse events (AEs) were pooled using a random-effects model. Results Nine studies including 380 patients with long-term transmural PS and 289 patients without PS were identified. The rate of PFC recurrence was significantly lower in patients with transmural PS (pooled odds ratio [OR] = 0.23, 95% confidence interval [CI] [0.08-0.65], P = 0.005). In a subgroup analysis limited to studies focusing on patients with disconnected pancreatic duct syndrome, which has been reported to be a risk factor for PFC recurrence, the OR was numerically lower than that for the entire cohort (OR = 0.14, 95% CI [0.04-0.46]). The rate of AEs was significantly higher with long-term transmural PS (OR = 14.77, 95% CI [4.21-51.83]). Conclusions In this meta-analysis, long-term PS placement reduced the risk of PFC recurrence. Given the potential AEs of indwelling PS, further research is required to evaluate the overall benefits of long-term PS placement.

Controversies in the management of acute pancreatitis: An update

This review summarized the current controversies in the management of acute pancreatitis (AP). The controversies in management range from issues involving fluid resuscitation, nutrition, the role of antibiotics and antifungals, which analgesic to use, role of anticoagulation and intervention for complications in AP. The interventions vary from percutaneous drainage, endoscopy or surgery. Active research and emerging data are helping to formulate better guidelines. The available evidence favors crystalloids, although the choice and type of fluid resuscitation is an area of dynamic research. The nutrition aspect does not have controversy as of now as early enteral feeding is preferred most often than not. The empirical use of antibiotics and antifungals are gray zones, and more data is needed for conclusive guidelines. The choice of analgesic is being studied, and the recommendations are still evolving. The position of using anticoagulation is still awaiting consensus. The role of intervention is well established, although the modality is constantly changing and favoring endoscopy or percutaneous drainage rather than surgery. It is evident that more multicenter randomized controlled trials are required for establishing the standard of care in these crucial management issues of AP to improve the morbidity and mortality worldwide.

A case of walled-off necrosis extending into the pelvic cavity successfully treated by endoscopic necrosectomy using a lumen-apposing metal stent

A 31‐year‐old man developed massive walled‐off necrosis extending into the pelvic cavity following severe acute alcoholic pancreatitis. Endoscopic ultrasound‐guided fistula drainage was performed using a lumen‐apposing metal stent, but this was insufficiently effective, and endoscopic necrosectomy was also performed, after which the patient improved. Percutaneous drainage and surgery are other options for the treatment of walled‐off necrosis extending into the pelvic cavity, but a valuable case in which the patient improved with endoscopic treatment alone is presented.

The Role of EUS-Guided Drainage in the Management of Postoperative Fluid Collections after Pancreatobiliary Surgery

Postoperative fluid collection (POFC) is a challenging complication following pancreatobiliary surgery. Traditional treatment with surgical drainage is associated with significant morbidity, while percutaneous drainage is associated with a higher rate of recurrence and the need for repeated interventions. Studies have shown that endoscopic ultrasound (EUS)-guided drainage may offer a promising solution to this problem. There are limited data on the ideal therapeutic protocol for EUS-guided drainage of POFC including the timing for drainage; type, size, and number of stents to use; and the need for endoscopic debridement and irrigation. Current practices extrapolated from the treatment of pancreatic pseudocysts and walled-off necrosis may not be applicable to POFC. There are increasing data to suggest that drainage procedures may be performed within two weeks after surgery. While most authors advocate the use of double pigtail plastic stents (DPPSs), there have been a number of reports on the use of novel lumen-apposing metal stents (LAMSs), although no direct comparisons have been made between the two.

The Role of Lumen-Apposing Metal Stents in Transmural Endoscopic Drainage of Postinflammatory Pancreatic and Peripancreatic Fluid Collections

Rapid development of advanced gastrointestinal endoscopic techniques contributed to the appearance of new biomedical materials including polymers, which are used for the production of different types of endoprostheses. Endotherapy (ET) of postinflammatory pancreatic and peripancreatic fluid collections (PPFCs) with the use of lumen-apposing metal stent (LAMS) is an effective method of treatment. This paper describes the high efficacy of ET and its potential complications, which are mostly related to the design of the LAMS used. The high efficacy of LAMS in the transmural drainage of PPFCs is associated with lower safety of treatment. Complications of ET presented in the manuscript are mainly related to endoprosthesis' construction. This paper presents possible directions of development in the field of transmural LAMSs, which in the future may contribute to the invention of an innovative type of LAMS based on new biomedical technologies. Possibly, subsequent novel endoprosthesis projects, based on the above results, will be able to meet the current needs and requirements associated with endoscopic transmural drainage procedures in cases of postinflammatory PPFCs. The ultimate goal is to improve safety of minimally invasive techniques for treatment of the local consequences of pancreatitis.

[Endoscopic transluminal interventions in the treatment of acute necrotizing pancreatitis]

The review is devoted to endoscopic transluminal interventions in the treatment of acute necrotizing pancreatitis. Terminology, indications and options for transluminal drainage procedures and endoscopic sequestrectomy are presented in detail. The authors analyzed the results of numerous studies devoted to effectiveness of endoscopic interventions and possible combination of treatment options. Modern international clinical guidelines indicating the feasibility of endoscopic treatment of acute necrotizing pancreatitis in multi-field specialized centers are considered.

EUS-guided drainage of pancreatic fluid collection, using a modified technique of cystotome alone without a FNA needle

BACKGROUND

Endoscopic ultrasound (EUS)-guided drainage for pancreatic fluid collection (PFC) involves puncture with a fine-needle aspiration (FNA) needle, followed by tract dilation involving exchange of multiple accessories, and finally deployment of stent. The procedure is time consuming and carries a risk of loss of wire access and hence technical failure. We used a modified technique with a 10-F cystotome alone instead of a FNA needle and dilators.

METHODS

We retrospectively analysed records of consecutive patients who had undergone EUS-guided drainage of PFC using a modified technique, with puncture of PFC using a 10-Fcystotome, followed by passage of a guidewire through it into the PFC cavity and deployment of a biflanged, 2-cm-long, fully covered self-expanding metal stent over it. Technical and clinical success rates and procedure time were assessed.

RESULTS

Forty-five patients underwent PFC drainage, median age was 35 (12-76), and 35 (77.8%) were males. The median (range) duration of symptoms was 125 (38-1080) days, while the median PFC size was 11.8 × 11 × 11 cm, and the follow-up period after stent removal was 111 ± 72 (18-251) weeks. The procedure took 10 (8-12) min and had technical and clinical success rates of 100 and 97.8%, respectively. Minor complications occurred in six (13.3%) patients, while recurrence occurred in one.

CONCLUSION

EUS-guided drainage of PFC using a cystotome is a quick, effective and safe procedure. It may also be less expensive since it obviates the use of FNA needles and dilators, and is likely to be a useful alternative to the conventional technique.

Management of walled-off necrosis with nasocystic irrigation with hydrogen peroxide versus biflanged metal stent: randomized controlled trial

Background and study aims  Walled-off necrosis (WON) is a known complication of acute necrotizing pancreatitis (ANP). There is no study comparing nasocystic irrigation with hydrogen peroxide (H ₂ O ₂ ) versus biflanged metal stent (BMS) in the management of WON. The aim of this study was to compare the clinical efficacy of both the treatment strategies. Patients and methods  This study was conducted on patients with symptomatic WON who were randomized to nasocystic irrigation with H ₂ O ₂ (Group A) and BMS placement (Group B). Primary outcomes were clinical and technical success while secondary outcomes were procedure time, adverse events, need for additional procedures, duration of hospitalization, and mortality. Results  Fifty patients were randomized into two groups. Group A (n = 25, age 37.8 ± 17.6 years, 16 men) and Group B (n = 25, age 41.8 ± 15.2 years, 17 men). There were no significant differences in baseline characteristics between the two groups. The most common etiology of pancreatitis was alcohol, observed in 27 (54 %) patients. Technical success (100 % vs 96 %, P  = 0.98), clinical success (84 % vs 76 %, P  = 0.76), requirement of additional procedures (16 % vs 24 %, P  = 0.70) and adverse events (4 vs 7, P  = 0.06) were comparable in both the groups. The duration to clinical success (34.4 ± 12 vs 14.8 ± 10.8 days, P  = 0.001) and procedure time (36 ± 15 vs 18 ± 12 minutes, P  = 0.01) were longer in Group A compared to Group B. Conclusions  Nasocystic irrigation with H ₂ O ₂ and BMS are equally effective in the management of WON but time to clinical success and procedure time is longer with nasocystic irrigation.

International, multicenter retrospective trial comparing the efficacy and safety of bi-flanged versus lumen-apposing metal stents for endoscopic drainage of walled-off pancreatic necrosis

Background

To compare fully covered bi-flanged metal stents (BFMS) and lumen-apposing metal stents (LAMS) for endoscopic ultrasound (EUS)-guided drainage/debridement of pancreatic walled-off necrosis (WON).

Methods

Patients with WON managed by EUS-guided therapy were divided into those who underwent: 1) drainage using BFMS; and 2) drainage using LAMS and scheduled direct endoscopic necrosectomy (DEN). Clinical success (resolution of the WON), technical success (successful stent placement), and adverse events (AEs) were evaluated.

Results

387 patients underwent WON endoscopic drainage, 205 using BFMS and 182 using LAMS. The clinical success in the BFMS or LAMS groups were similar (197 [96.1%] vs. 174 [95.6%]; P=0.81). Median number of procedures required for WON resolution was significantly lower in BFMS compared to LAMS (2 vs. 3, P<0.001). Technical success for stent placement was similar in BFMS and LAMS groups (203 [99%] vs. 180 [99%], P=0.90). Procedure-related AEs were similar in the BFMS and LAMS groups (19 [9.3%] vs. 20 [10.9%], P=0.61). Stent dysfunction with occluding debris was higher in the BFMS group compared to LAMS group (21 [10.2 %] vs. 11 [5.9%], P=0.04). The migration rate was higher in the BFMS group than in the LAMS group (15 [7.3%] vs. 3 [1.6%]; P<0.001). DEN was required in 23 [11.2%] patients in the BFMS group after lack of WON resolution by conservative means.

Conclusion

BFMS with a “step-up approach” and LAMS with scheduled DEN are both safe and effective for EUS-guided drainage/debridement of WON.

The role of endoscopic therapy in the minimally invasive management of pancreatic necrosis

Pancreatic necrosis is among the most frequently encountered local complications of acute pancreatitis and associates with severe disease. Infected pancreatic necrosis further enhances the risk for morbidity and mortality. Pancreatic fluid collections that result from pancreatic necrosis evolve from acute necrotic collections to walled off necrosis and are defined by their distinct characteristics on cross sectional imaging. A variety of interventions spanning multiple disciplines are available for the drainage and debridement of pancreatic necrosis. Prospective, randomized trials have identified management strategies that incorporate minimally invasive interventions as having the best outcomes for patients with symptomatic pancreatic necrosis. The scientific literature has confidently positioned endoscopic drainage and necrosectomy among the most effective interventions for patients with symptomatic walled off necrosis. Innovations such as the use of metallic stents, chemical debridement and multiple modalities for drainage of pancreatic necrosis show promise in improving outcomes for patients managed with endoscopic interventions.

When Should We Perform Endoscopic Drainage and Necrosectomy for Walled-Off Necrosis?

Endoscopic drainage and necrosectomy are now accepted treatment approaches for patients with symptomatic walled-off pancreatic necrosis (WON). The current recommendations advocate step-up approaches for the treatment of symptomatic WON. Previous recommendations stipulated that endoscopic intervention should be delayed until more than four weeks after the onset. Recent data on early drainage have been increasing and this option might be considered in well-encapsulated cases, but the percutaneous route is preferred if the drainage is performed within two weeks after onset or in nonencapsulated cases. Recently, additional drainage methods, such as the multiple gateway technique and multiple stent placement, have been developed to open up multiple dead spaces in the WON cavity. Endoscopic necrosectomy could be performed via the transluminal route or percutaneous route after failed initial and additional drainage procedures. The use of novel lumen-apposing stents is a promising treatment option that could reduce the number of steps, the procedure time, and the overall number of necrosectomies.

Efficacy and safety of plastic versus lumen-apposing metal stents for transmural drainage of walled-off necrosis: a retrospective single-center study

Background

Lumen-apposing metal stents (LAMS) were considered a breakthrough in the endoscopic management of walled-off necrosis (WON), as their larger drainage diameter was expected to provide effective drainage of necrotic material. However, various studies and meta-analyses that have compared plastic and metal stents for the treatment of WON have shown conflicting results. We retrospectively compared the efficacy and safety of endoscopic transmural drainage between multiple plastic stents and LAMS.

Methods

Endoscopic data were retrospectively retrieved for patients who had undergone endoscopic ultrasound (EUS)-guided drainage/debridement of WON. Patients were divided into 2 groups according to whether multiple plastic stents or LAMS were deployed during initial drainage. The resolution and complication rates were compared between the 2 groups.

Results

One hundred sixty-six patients (83% male, mean age 37.5 years) with symptomatic WON were treated with EUS-guided drainage using either multiple plastic stents (n=138) or LAMS (n=28). Patients in the LAMS group had significantly larger WON and a significantly higher proportion of solid content. WON resolution rates did not differ between plastic stents and LAMS (98.5% vs. 96.4% respectively, P=0.42). However, the time taken to resolution was significantly shorter in the LAMS group than in the plastic stents group (26.7 vs. 29.8 days, P=0.03). There was no significant difference between the groups in either mortality or complication rates.

Conclusions

The technical success, rates of WON resolution and complications were similar in patients treated with multiple plastic stents and LAMS. However, LAMS were associated with a significantly shorter time to resolution.

Advancements in the endoscopic treatment of pancreatic fluid collections

Endoscopic drainage of pancreatic fluid collections (PFCs) with fewer complications and less trauma has gradually replaced surgery or percutaneous drainage to become the first-line treatment for PFCs. In recent years, the differential efficacy of various stent techniques to drain different types of PFCs has been controversial. This review summarizes the clinical applications of endoscopic ultrasound-guided stent placement for PFCs drainage.

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.

Lumen-apposing metal stents versus biliary fully-covered metal stents for EUS-guided drainage of pancreatic fluid collections: a case control study: Meeting presentations: European Society of Gastrointestinal Endoscopy ESGE Days 2018

Background and study aims  Endoscopic ultrasound (EUS)-guided drainage has become first-line treatment for pancreatic fluid collections (PFC). The aim of this study was to compare the effectiveness and safety of biliary fully-covered self-expandable metal stents (BFCSEMS) and lumen-apposing metal stents with electrocautery (EC-LAMS). Patients and methods  From April 2008 to March 2017, consecutive patients with symptomatic PFC drained under EUS-guidance with metal stents were included. Patients drained with EC-LAMS were considered the study group and those drained with BFCSEMS the control group. Two primary endpoints were evaluated: effectiveness (defined as reduction of ≥ 50 % of PFC size in cross-sectional imaging and improvement of symptoms 6 months after the transmural drainage) and safety. Results  Thirty patients were drained with EC-LAMS and 60 patients with BFCSEMS. Patients and PFC baseline characteristics in both groups were similar. Use of a coaxial double pigtail plastic stent and a nasocystic lavage catheter was significantly less frequent in patients drained with EC-LAMS (33 % vs. 100 %, and 13 % vs. 58 %, respectively; P  < 0.0001). Technical success was 100 % in both groups. Procedure time was < 30 minutes in all patients drained with EC-LAMS and over 30 minutes in all patients drained with BFCSEMS ( P  = 0.0001). Clinical success was higher with a tendency to significance in patients drained with EC-LAMS (96 % vs. 82 %, P  = 0.055) and the adverse event rate was lower (4 % vs. 18 %, P  = 0.04). No case of procedure-related mortality was recorded. Conclusions  EC-LAMS and BFCSEMS are both effective for EUS-guided drainage of PFC. However, EC-LAMS requires less time to be performed and appears to be safer.

Various Endoscopic Techniques for Treatment of Consequences of Acute Necrotizing Pancreatitis: Practical Updates for the Endoscopist

Despite great progress in acute pancreatitis (AP) treatment over the last 30 years, treatment of the consequences of acute necrotizing pancreatitis (ANP) remains controversial. While numerous reports on minimally invasive treatment of the consequences of ANP have been published, several aspects of interventional treatment, particularly endoscopy, are still unclear. In this article, we attempt to discuss these aspects and summarize the current knowledge on endoscopic therapy for pancreatic necrosis. Endotherapy has been shown to be a safe and effective minimally invasive treatment modality in patients with consequences of ANP. The evolution of endoscopic techniques has made endoscopic drainage more effective and reduced the use of other minimally invasive therapies for pancreatic necrosis.

A novel lumen-apposing metal stent with an anti-reflux valve for endoscopic ultrasound-guided drainage of pseudocysts and walled-off necrosis: A pilot study

BACKGROUND

Pancreatic pseudocysts (PC) and walled-off necrosis (WON) are common complications of severe pancreatitis. Endoscopic ultrasound (EUS)-guided drainage has replaced surgery as the standard treatment for PC/WON. We developed a novel lumen-apposing metal stent (LAMS) with an anti-reflux valve to prevent infectious complications caused by food reflux into the cyst cavity. This retrospective study investigated the efficacy and safety of EUS-guided drainage using this LAMS.

METHODS

We investigated and compared the treatment outcomes and complications rates between EUS-guided drainage using a novel LAMS (n = 10) versus plastic stents (n = 18) from December 2013 to October 2016. Technical success was defined as successful stent placement without immediate complications. Clinical success was defined as resolution of the PC/WON and disappearance of symptoms.

RESULTS

Among 10 patients in LAMS group, 4 patients had complicated PC and 6 patients had WON. In the plastic stent group, 15 and 3 patients had PC and WON, respectively. The median fluid collection size before treatment was 82.5 (interquartile range [IQR], 60.75-118.25) mm and 92.0 (IQR, 75.75-130.25) mm in the LAMS and plastic stent groups, respectively. There were no statistically significant differences in technical success rates (90% vs. 94.4%; p = 0.999), clinical success rates (80% vs. 77.8%; p = 0.999), and complication rates (20% vs. 27.8%; p = 0.999) between the two groups.

CONCLUSIONS

Treatment outcomes of EUS-guided drainage using a novel LAMS were feasible despite the significantly high proportion of WON. The LAMS allowed acceptable treatment outcomes for EUS-guided drainage.

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

OBJECTIVE

Although lumen-apposing metal stents (LAMS) are increasingly used for drainage of walled-off necrosis (WON), their advantage over plastic stents is unclear. We compared efficacy of LAMS and plastic stents for WON drainage.

DESIGN

Patients with WON were randomised to endoscopic ultrasound-guided drainage using LAMS or plastic stents. Primary outcome was comparing total number of procedures to achieve treatment success defined as symptom relief in conjunction with WON resolution on CT at 6 months. Secondary outcomes were treatment success, procedure duration, clinical/stent-related adverse events, readmissions, length of hospital stay (LOS) and costs.

RESULTS

60 patients underwent LAMS (n=31) or plastic stent (n=29) placement. There was no significant difference in total number of procedures performed (median 2 (range 2-7) LAMS vs 3 (range 2-7) plastic, p=0.192), treatment success, clinical adverse events, readmissions, LOS and overall treatment costs between cohorts. Although procedure duration was shorter (15 vs 40 min, p<0.001), stent-related adverse events (32.3% vs 6.9%, p=0.01) and procedure costs (US$12 155 vs US$6609, p<0.001) were higher with LAMS. Significant stent-related adverse events were observed ≥3 weeks postintervention in LAMS cohort. Interim audit resulted in protocol amendment where CT scan was obtained at 3 weeks postintervention followed by LAMS removal if WON had resolved. After protocol amendment, there was no significant difference in adverse events between cohorts.

CONCLUSION

Except for procedure duration, there was no significant difference in treatment outcomes between LAMS and plastic stents. To minimise adverse events with LAMS, patients should undergo follow-up imaging and stent removal at 3 weeks if WON has resolved.

TRIAL REGISTRATION NUMBER

NCT02685865.

Multivariate analysis of the factors affecting the prognosis of walled-off pancreatic necrosis after endoscopic ultrasound-guided drainage

BACKGROUND AND AIMS

Endoscopic ultrasound (EUS)-guided drainage has become the treatment of choice for walled-off pancreatic necrosis (WOPN). However, no consensus exists on the most significant patient- and procedure-related factors that affect prognosis. The aim of the study is to investigate the correlation between patient- and procedure-related factors and post-procedure complications after EUS-guided drainage.

METHODS

A retrospective analysis of the clinical characteristics of patients with WOPN who underwent EUS-guided drainage at our endoscopy center between November 2011 and August 2017 was performed. Chi-square analysis and binary logistic regression statistical methods were used to analyze the correlation between influencing factors and prognosis.

RESULTS

A total of 85 patients (male/female, 50/35) with WOPN were included in the study. The average age was 44.95 years. The cyst diameter was 10.58 ± 4.78 cm. Multivariate analysis showed that WOPN with higher solid content (> 30%) increased the probability of endoscopic necrosectomy (OR 6.798; 95% CI 1.423, 32.470; p = 0.016). The use of a metal stent increased the probability of endoscopic necrosectomy (OR 3.503; 95% CI 1.251, 9.810; p = 0.017) and the length of hospitalization (OR 3.315; 95% CI 1.192, 9.215; p = 0.022). Female patients had a higher probability of requiring endoscopic necrosectomy (OR 2.683; 95% CI 1.027, 7.007; p = 0.044) and prolonged hospitalization (OR 2.675; 95% CI 1.065, 6.721; p = 0.036).

CONCLUSION

The solid content of WOPN, type of stent, and sex of patients were associated with increased probability of endoscopic necrosectomy.

A systematic review and meta-analysis of metal versus plastic stents for drainage of pancreatic fluid collections: metal stents are advantageous

BACKGROUND

The use of fully covered metal stents (FCSEMS) and specifically designed lumen apposing metal stents for transmural drainage of pancreatic fluid collections has become widespread. A systematic review published in 2015 did not support the routine use of metal stents for drainage of pancreatic fluid collections. However, recent studies have shown conflicting data; therefore a systematic review and meta-analysis was performed.

METHOD

We conducted a database search for original comparative studies between plastic and metal stents. The random effects model was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI). Outcomes analysed were clinical success, adverse events and requirement of further intervention.

RESULTS

The search identified 936 studies, 7 studies with 681 (340 metal, 341 plastic) patients met inclusion criteria and were included in the meta-analysis. Clinical success was achieved in 93.8% versus 86.2% in the metal and plastic groups, respectively, RR 1.08 [95% CI 1.02-1.14]; p = 0.009. Adverse events were reduced for metal stents when compared with plastic (10.2% vs. 25.0%), RR 0.42 [95% CI 0.22-0.81]; p = 0.010. Metal stent usage reduced bleeding (2.8% vs. 7.9%), RR 0.37; [95% CI 0.18-0.75]; p = 0.006. Further intervention was required in 12.4% of patients in the metal stent group versus 26.7% for plastic stents, RR 0.54; [95% CI 0.22-1.29]; p = 0.165.

CONCLUSIONS

The use of metal stents for drainage of pancreatic fluid collections is associated with improved clinical success, fewer adverse events and reduced bleeding compared to plastic stents.

Lumen apposing metal stents in drainage of pancreatic walled-off necrosis, are they any better than plastic stents? A systematic review and meta-analysis of studies published since the revised Atlanta classification of pancreatic fluid collections

Lumen-apposing metal stents (LAMS) are increasingly being used in the drainage of pancreatic walled-off necrosis (WON). Best choice of stent is subject to argument, and studies are varied in the reported outcomes between LAMS and plastic stents (PS) to this end. We conducted a comprehensive search of multiple electronic databases and conference proceedings including PubMed, EMBASE, and Web of Science databases (earliest inception through July 2018) to identify studies that reported on the use of LAMS and PS in WON drainage. Studies published since the release of the revised Atlanta classification for pancreatic fluid collections (2014 to current) were included in the analysis. The outcomes were to estimate and compare the pooled rates of clinical success, and adverse-events. A total of 9 studies (737 patients) for LAMS and 6 studies (527 patients) for PS were included in the analysis. The pooled rate of clinical-success with LAMS was 88.5% (95% CI 82.5-92.6, I² = 71.7) and with PS was 88.1% (95% CI 80.5-93.0, I² = 78.1) and the difference was not statistically significant, P = 0.93. No difference was noted in the pooled rates of all adverse-events, LAMS: 11.2% (6.8-17.9, I² = 82.0); vs PS: 15.9% (8.4-27.8, I² = 78.8); P = 0.38. Based on our meta-analysis, LAMS and PS demonstrate equal clinical outcomes and equal adverse-events in the drainage of pancreatic WON.

Algorithm for the multidisciplinary management of hemorrhage in EUS-guided drainage for pancreatic fluid collections

Pancreatic fluid collections (PFCs), common sequelae of acute or chronic pancreatitis, are broadly classified as pancreatic pseudocysts or walled-off necrosis according to the revised Atlanta classification. Endoscopic ultrasound (EUS)-guided drainage is often considered a standard first-line therapy preferable to surgical or interventional radiology approaches for patients with symptomatic PFC. EUS-guided drainage is effective and successful; it has a technical success rate of 90%-100% and a clinical success rate of 85%-98%. Recent studies have shown a 5%-30% adverse events (AEs) rate for the procedure. The most common AEs include infection, hemorrhage, perforation and stent migration. Hemorrhage, a severe and sometimes deadly outcome, requires a well-organized and appropriate treatment strategy. However, few studies have reported the integrated management of hemorrhage during EUS-guided drainage of PFC. Establishing a practical therapeutic strategy is an essential and significant step in standardized management. The aim of this review is to describe the current situation of EUS-guided drainage of PFCs, including the etiology and treatment of procedure-related bleeding as well as current problems and future perspectives. We propose a novel and meaningful algorithm for systematically managing hemorrhage events. To our limited knowledge, a multidisciplinary algorithm for managing EUS-guided drainage for PFC-related bleeding has not been previously reported.

The Evolution of EUS-Guided Transluminal Drainage for the Treatment of Pancreatic Fluid Collections: A Comparison of Clinical and Cost Outcomes with Double-Pigtail Plastic Stents, Conventional Metal Stents and Lumen-Apposing Metal Stents

Background

While most pancreatic fluid collections (PFCs) resolve spontaneously, endoscopic ultrasound-guided transluminal drainage (EUS-TD) may be necessary. EUS-TD has evolved from multiple double-pigtail plastic stents (DPPS) to fully covered self-expanding metal stents (FCSEMS) and lumen-apposing metal stents (LAMS). This study compares clinical attributes of DPPS, FCSEMS and LAMS.

Methods

This is a single-centre retrospective review of EUS-TD for PFCs. The primary outcome was clinical success. Secondary outcomes were technical success, procedure time, hospital length of stay (HLOS), number of endoscopies, need for necrosectomy, adverse events (AEs) and overall cost.

Results

Fifty-eight patients (37 male, average age 49 years) underwent a total of 60 EUS-TD procedures for PFCs (average size 11.2 cm with 29 pseudocysts and 29 walled-off necrosis). Ten patients (17%) underwent EUS-TD with DPPS and 48 patients (83%) with metal stents (32 FCSEMS, 16 LAMS). Overall technical and clinical success was 100% and 84%, respectively. Lumen-apposing metal stents had shorter procedure times (14.9 versus 63.6 DPPS, 39.1 min FCSEMS, P < 0.001), and no difference in AEs (3 of 16 versus 4 of 10 DPPS, 12 of 34 FCSEMS, ns). Double-pigtail plastic stents required more endoscopies (3.7 versus 2.3 LAMS, 2.3 FCSEMS, P = 0.013) and necrosectomies (4 of 10 [40%]) compared with 5 of 34 [15%] in the FCSEMS group and 3 of 16 [19%] in the LAMS group, respectively, P = 0.001) to achieve clinical resolution. The overall cost and HLOS was not significantly different between groups.

Conclusion

The use of LAMS for PFCs is not associated with any significant increase in cost despite technical (shorter procedure time) and clinical advantages (shorter indwell time, reduced need for necrosectomy and no increase in AEs).

Endoscopic Management of Infected Necrotizing Pancreatitis: an Evidence-Based Approach

PURPOSE OF REVIEW

Endoscopic management of infected necrotizing pancreatitis has evolved rapidly over the past years and there have been interesting innovations in this field. This review provides an update on the most recently published literature regarding endoscopic management of infected necrotizing pancreatitis.

RECENT FINDINGS

A recent randomized trial demonstrated no difference in mortality and major morbidity between endoscopic and surgical step-up treatment of infected necrotizing pancreatitis. However, endoscopic therapy resulted in shorter hospital stay and less pancreatic fistulas. Various innovations have been investigated with the aim to further optimize endoscopic therapy, in particular lumen-apposing metal stents. While major stent-related complications were also reported, findings from recent studies indicated that their use was associated with higher resolution rates of walled-off necrosis compared to double-pigtail stents. Other innovations, such as the multiple gateway technique and dual-modality mode, can be considered for treatment of particular cases. Furthermore, research suggests that irrigation of walled-off necrosis can be performed by using a nasocystic tube and discontinuation of proton-pump inhibitors may be considered. Endoscopic treatment should be the preferred treatment modality in patients with infected necrotizing pancreatitis who are eligible for endoscopic drainage. Although data suggests that lumen-apposing metal stents are superior to double-pigtail stents, prospective multicenter studies focusing on safety as well as long-term follow-up are first needed.

Comparing efficacy of lumen-apposing stents to plastic stents in the endoscopic management of mature peripancreatic fluid collections: a single-center experience

Introduction

Mature peripancreatic fluid collection (MPFC) is a known and often challenging consequence of acute pancreatitis and often requires intervention. The most common method accepted is the “step-up approach,” which consists of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. Our paper aims to distinguish between plastic stents and lumen-apposing stents in the endoscopic management of MPFC in terms of morbidity, mortality, and haste of fluid collection resolution.

Methods

A retrospective analysis was performed at UMass Memorial Medical Center in patients with a diagnosis of MPFC. Utilizing medical records, clinical data, radiology, as well as endoscopic evidence, patients were differentiated by stent type used (plastic versus lumen-apposing) for the management of the MPFC. The primary outcome of the study was to assess the time to MPFC resolution following the placement of either plastic or lumen-apposing stents (on endoscopic ultrasound or computerized tomography scan) using a multivariate analysis with a logistic regression model.

Results

A total of 54 patients were included in this study from UMass Memorial Medical Center between 2012 and 2015. Twelve (22%) of these patients received lumen-apposing stents and 42 (78%) of these patients received plastic pigtail stents. For the lumen-apposing stent group, the mean interval between stent placement and resolution of MPFC was 57 days as compared to 102 days for plastic pigtail stents (p=0.02). The mean interval for placement/removal of lumen-apposing stents was 48 days as compared to 81 days for plastic pigtail stents (p=0.01). Stent migration was seen in 5 patients (11%) who received a plastic pigtail stent compared to 0 (0%) patients who received a lumen-apposing stent.

Discussion

Our study demonstrates that lumen-apposing stents result in a significant reduction in the interval between stent placement and MPFC resolution as well as the time from stent placement to removal, when compared to plastic pigtail stents, the prior standard-of-care. Our study reached similar conclusions regarding the number of stents placed. However, we did not find a significant difference between the complication rates, specifically peri- and postprocedural bleeding or perforation, between the 2 study groups, as demonstrated in prior papers.

The Role of Endoscopic Ultrasound-guided Drainage for Autoimmune Pancreatitis-associated Pancreatic Cysts: A Report of Five Cases and a Literature Review

Objective Autoimmune pancreatitis (AIP) has been recognized as a benign disease, which that shows a prompt response to corticosteroid treatment (CST). It was previously believed to not be associated with cyst formation; however, a few cases of AIP-associated pancreatic cyst (PC) have been reported. Some cases were reported to have been effectively treated by CST, while others were refractory to CST. Many of the patients received interventional treatment. Until now, there has been no consensus on the therapeutic strategies for AIP-associated PC. The aim of the present study is to describe a therapeutic strategy for this condition. Methods We conducted a retrospective study of 5 cases of AIP-associated PC that were treated by endoscopic ultrasonography-guided pancreatic fluid collection drainage (ESPD) or CST at Tokyo Medical University Hospital between March 2012 and October 2016, analyzed the therapeutic outcomes, and performed a literature review. Results The initial treatments included CST (n=2) and ESPD (n=3). All of the PCs disappeared after treatment In 1 of the patients who received CST case and 3 of the patients who received ESPD; however, the PC did not disappear in one of the patients who received CST (corticosteroid maintenance therapy), even after the dose of corticosteroids was increased; ESPD was eventually performed and the PC disappeared. There were no procedure-related complaints. Conclusion We propose that CST be administered as the first-line treatment for AIP-associated PC, particularly in cases of PC without a history of CST. However, ESPD can be applied to treat cases of corticosteroid refractory PC.

Endoscopic Management of Peri-Pancreatic Fluid Collections

In the past decade, there has been a progressive paradigm shift in the management of peri-pancreatic fluid collections after acute pancreatitis. Refinements in the definitions of fluid collections from the updated Atlanta classification have enabled better communication amongst physicians in an effort to formulate optimal treatments. Endoscopic ultrasound (EUS)-guided drainage of pancreatic pseudocysts has emerged as the procedure of choice over surgical cystogastrostomy. The approach provides similar success rates with low complications and better quality of life compared with surgery. However, an endoscopic "step up" approach in the management of pancreatic walled-off necrosis has also been advocated. Both endoscopic and percutaneous drainage routes may be used depending on the anatomical location of the collections. New-generation large diameter EUS-specific stent systems have also recently been described. The device allows precise and effective drainage of the collections and permits endoscopic necrosectomy through the stents.

Endoscopic versus percutaneous management for symptomatic pancreatic fluid collections: a systematic review and meta-analysis

BACKGROUND

 Symptomatic pancreatic fluid collections (PFCs) are managed by surgical, percutaneous, or endoscopic drainage. Due to morbidity associated with surgical drainage, percutaneous and/or endoscopic options have increasingly been used as initial management.

AIMS

 We conducted a systematic review and meta-analysis comparing the efficacy and safety of endoscopic versus percutaneous drainage for management of PFCs.

METHODS

 We searched several databases from inception through 31 August 2017 to identify comparative studies using endoscopic or percutaneous drainage for PFCs. Our primary outcome was clinical success. Secondary outcomes were technical success, adverse events (AE), rates of recurrence, requirement for subsequent procedures, and length of stay in hospital. Pooled risk ratios (RR) and mean difference (MD) were calculated for categorical and continuous outcomes, respectively.

RESULTS

 Seven studies with 490 patients were included in the final analysis. Pooled RR for clinical success was 0.40 (0.26, 0.61), I²  = 42 % in favor of endoscopic management. On sensitivity analysis, after excluding one study on patients with walled-off necrosis (WON), the clinical success was 0.43 (0.28, 0.66) with no heterogeneity. Pooled RR for technical success was 1.50 (0.52, 4.37) with no heterogeneity. Pooled RR for AE and rate of recurrence were 0.77 (0.46, 1.28) and 0.60 (0.29, 1.24), respectively. Pooled MD for length of stay in hospital and rate of re-intervention were - 8.97 (- 12.88, - 5.07) and - 0.66 (- 0.93, - 0.38), respectively, in favor of endoscopic drainage.

CONCLUSIONS

 Endoscopic drainage should be the preferred therapeutic modality for PFCs compared to percutaneous drainage as it is associated with significantly better clinical success, a lower re-intervention rate, and a shorter hospital length of stay.

Metal versus plastic stents for drainage of pancreatic fluid collection: A meta-analysis

Background

Although metal stents are increasingly being used for endoscopic transmural drainage of pancreatic fluid collection (PFC), the advantages of metal stents in comparison with plastic stents are not clear.

Objective

The aim of this study is to compare the clinical outcomes and adverse events between patients receiving endoscopic transmural drainage of PFCs through metal or plastic stents.

Methods

We performed a systematic literature search to identify all published manuscripts comparing metal and plastic stents for PFC drainage. The primary outcome was clinical success, and the secondary outcomes were technical success, procedure time, overall cost, adverse events, and recurrence.

Results

Seven studies were considered to be appropriate for this meta-analysis. Metal stents showed a higher clinical success rate (odds ratio (OR) 3.39, 95% confidence interval (CI) 2.05-5.60) and a lower overall adverse event rate (OR 0.37, 95% CI 0.21-0.66) than plastic stents. In subgroup analyses, metal stents showed higher clinical success rates than plastic stents both for pseudocyst (OR 5.35, 95% CI 1.35-21.19) and walled-off necrosis (OR 3.37, 95% CI 1.89-5.99).

Conclusions

Metal stents are superior to plastic stents for endoscopic transmural drainage of PFC because they have a higher clinical success rate and lower rate of adverse events.

Short- and long-term results of endoscopic ultrasound-guided transmural drainage for pancreatic pseudocysts and walled-off necrosis

AIM

To evaluate the short- and long-term results of endoscopic ultrasound-guided transmural drainage (EUS-GTD) for pancreatic fluid collection (PFC) and identify the predictive factors of treatment outcome for walled-off necrosis (WON) managed by EUS-GTD alone.

METHODS

We investigated 103 consecutive patients with PFC who underwent EUS-GTD between September 1999 and August 2015. Patients were divided into four groups as follows: WON (n = 40), pancreatic pseudocyst (PPC; n = 11), chronic pseudocyst (n = 33), and others (n = 19). We evaluated the short- and long-term outcomes of the treatment. In cases of WON, multiple logistic regression analyses were performed to identify the predictor variables associated with the treatment success. In addition, PFC recurrence was examined in patients followed up for more than 6 mo and internal stent removal after successful EUS-GTD was confirmed.

RESULTS

In this study, the total technical success rate was 96.1%. The treatment success rate of WON, PPC, chronic pseudocyst, and others was 57.5%, 90.9%, 91.0%, and 89.5%, respectively. Contrast-enhanced computed tomography using the multivariate logistic regression analysis revealed that the treatment success rate of WON was significantly lower in patients with more than 50% pancreatic parenchymal necrosis (OR = 17.0; 95%CI: 1.9-150.7; P = 0.011) and in patients with more than 150 mm of PFC (OR = 27.9; 95%CI: 3.4-227.7; P = 0.002).The recurrence of PFC in the long term was 13.3% (median observation time, 38.8 mo). Mean amylase level in the cavity was significantly higher in the recurrence group than in the no recurrence group (P = 0.02).

CONCLUSION

The reduction of WON by EUS-GTD alone was associated with the proportion of necrotic tissue and extent of the cavity. The amylase level in the cavity may be a predictive factor for recurrence of PFC.

Lumen apposing metal stents for pancreatic fluid collections: Recognition and management of complications

For patients recovering from acute pancreatitis, the development of a pancreatic fluid collection (PFC) predicts a more complex course of recovery, and introduces difficult management decisions with regard to when, whether, and how the collection should be drained. Most PFCs resolve spontaneously and drainage is indicated only in pseudocysts and walled-off pancreatic necrosis when the collections are causing symptoms and/or local complications such as biliary obstruction. Historical approaches to PFC drainage have included surgical (open or laparoscopic cystgastrostomy or pancreatic debridement), and the placement of percutaneous drains. Endoscopic drainage techniques have emerged in the last several years as the preferred approach for most patients, when local expertise is available. Lumen-apposing metal stents (LAMS) have recently been developed as a tool to facilitate potentially safer and easier endoscopic drainage of pancreatic fluid collections, and less commonly, for other indications, such as gallbladder drainage. Physicians considering LAMS placement must be aware of the complications most commonly associated with LAMS including bleeding, migration, buried stent, stent occlusion, and perforation. Because of the patient complexity associated with severe pancreatitis, management of pancreatic fluid collections can be a complex and multidisciplinary endeavor. Successful and safe use of LAMS for patients with pancreatic fluid collections requires that the endoscopist have a full understanding of the potential complications of LAMS techniques, including how to recognize and manage expected complications.

Clinical impact of EUS treatment of walled-off pancreatic necrosis with dedicated devices

BACKGROUND AND STUDY AIMS

 Walled-off pancreatic necrosis (WOPN) represents the major risk factor for sepsis-related multiple organ failure. Surgical debridement is an invasive approach associated with high rates of adverse events (AEs) and death. As an alternative, endoscopic ultrasound-guided cysto-gastro-anastomosis has emerged as an effective treatment for WOPNs. Recently a new dedicated-lumen apposing metal stent (LAMS) has been used with satisfactory results in treating peri-pancreatic fluid collections, including WOPNs. The primary outcomes of this study were to evaluate survival and clinical success. Secondary outcomes included: technical success, adverse events and recurrence rate.

PATIENTS AND METHODS

 All consecutive patients with infected WOPN between February 2014 and June 2016 were retrospectively reviewed. Patients underwent placement of a new LAMS incorporated in an electrocautery-enhanced delivery system and direct endoscopic necrosectomy (DEN). DEN was performed immediately after stent deployment and repeated every 3 to 7 days until complete resolution.

RESULTS

 In the study period we treated 20 consecutive patients with infected WOPN using the new LAMS. Technical success was achieved in 95 % of patients. Clinical success was achieved in 73 % and 84.2 % of patients at 1 and 3 months, respectively. Survival rate was 84.2 % and 79 %. Mean length of hospital stay was 19 days (range 3 - 43). No AEs occurred. Patients were followed up after stent retrieval for a mean time of 554,7 days (range 70 - 986) and no recurrence was observed.

CONCLUSIONS

 DEN following "1-step, exchange-free" LAMS positioning recorded excellent results. We believe that simplicity of procedure plays a key role in terms of safety.

Efficacy and safety of metallic stents in comparison to plastic stents for endoscopic drainage of peripancreatic fluid collections: a meta-analysis and trial sequential analysis

Metallic stents are being increasingly used for endoscopic drainage of peripancreatic fluid collections (PFCs) but their superiority over plastic stents has not been proven. We carried out a meta-analysis to consolidate the results from available studies and to suggest evidence-based recommendations. Studies that compared plastic and metallic stents for endoscopic drainage of PFCs and published before October 2016 were searched. Comparisons were performed for clinical success, adverse events, salvage interventions, mortality, technical success and recurrence. We included six studies with 856 patients (479 in the metallic stent group and 377 in the plastic stent group). The clinical success rate was significantly higher with metallic stents than with plastic stents (Mantel-Haenszel odds ratio [MH-OR] 3.22; 95% CI 1.87-5.54; P < 0.001). The rate of adverse events (MH-OR 0.40; 95% CI 0.24-0.65; P < 0.001) and the need for salvage procedures (MH-OR 0.31; 95% CI 0.13-0.70; P = 0.01) were also significantly lower with the use of metallic stents. Subgroup analysis for the type of PFC also found better results with the metallic stents. The results of Egger's regression test (X-axis intercept at -0.63, P = 0.47) and funnel plot did not suggest any significant publication bias. We conclude that compared to plastic stents, the use of metallic stents for endoscopic drainage of PFCs is associated with significantly better clinical success and significantly lower rates of adverse events and the need for salvage procedures. However, further high-quality randomized trials are required to confirm these findings.

Endoscopic management of pancreatic fluid collections-revisited

The development of pancreatic fluid collections (PFC) is one of the most common complications of acute severe pancreatitis. Most of the acute pancreatic fluid collections resolve and do not require endoscopic drainage. However, a substantial proportion of acute necrotic collections get walled off and may require drainage. Endoscopic drainage of PFC is now the preferred mode of drainage due to reduced morbidity and mortality as compared to surgical or percutaneous drainage. With the introduction of new metal stents, the efficiency of endoscopic drainage has improved and the task of direct endoscopic necrosectomy has become easier. The requirement of re-intervention is less with new metal stents as compared to plastic stents. However, endoscopic drainage is not free of adverse events. Severe complications including bleeding, perforation, sepsis and embolism have been described with endoscopic approach to PFC. Therefore, the endoscopic management of PFC is a multidisciplinary affair and involves interventional radiologists as well as GI surgeons to deal with unplanned adverse events and failures. In this review we discuss the recent advances and controversies in the endoscopic management of PFC.

A multi-institutional consensus on how to perform endoscopic ultrasound-guided peri-pancreatic fluid collection drainage and endoscopic necrosectomy

There is a lack of consensus on how endoscopic ultrasound (EUS)-guided pseudocyst drainage and endoscopic necrosectomy should be performed. This survey was carried out amongst members of the EUS Journal Editorial Board to describe their practices in performing this procedure. This was a worldwide multi-institutional survey amongst members of the EUS Journal Editorial Board in May 2017. The responses to a 22-question survey with respect to the practice of EUS-guided pseudocyst drainage and endoscopic necrosectomy were obtained. Twenty-two endoscopists responded to the questionnaire as follows: 72.7% (16/22) were of the opinion that lumen-apposing metal stents (LAMS) should be the standard of care for the creation of an endoscopic cystenterostomy in patients with pancreatic walled-off necrosis (WON); 95.5% (21/22) recommended large diameter (d=15 mm) LAMS for drainage in patients with WON; 54.5% (12/22) would not dilate LAMS after placement into the WOPN; 86.4% (19/22) would not perform endoscopic necrosectomy during the same procedure as the creation of the cystenterostomy; 45.5% (10/22) recommend that agents, such as diluted hydrogen peroxide, should be used to lavage the peri-pancreatic fluid collection (PFC) cavity in patients with WON; and 45.5% (10/22) considered a naso-cystic or other tube to be necessary for lavage of WON after initial drainage. The mean optimal interval recommended for endoscopic necrosectomy procedures after EUS-guided drainage was 6.23 days. The mean optimal interval recommended for repeat imaging in patients undergoing endoscopic necrosectomy was 12.32 days. The mean time recommended for LAMS removal was 4.59 weeks. This is the first worldwide survey on the practice of EUS-guided pseudocyst drainage and endoscopic necrosectomy. There were wide variations in practice and randomized studies are urgently needed to establish the best approach for management of this condition. There is also a pressing need to establish a best practice consensus.

Management of acute pancreatitis in Japan: Analysis of nationwide epidemiological survey

Acute pancreatitis (AP) is an acute inflammatory disease of the exocrine pancreas. In Japan, nationwide epidemiological surveys have been conducted every 4 to 5 years by the Research Committee of Intractable Pancreatic Diseases, under the support of the Ministry of Health, Labour, and Welfare of Japan. We reviewed the results of the nationwide surveys focusing on the severity assessment and changes in the therapeutic strategy for walled-off necrosis. The severity assessment system currently used in Japan consists of 9 prognostic factors and the imaging grade on contrast-enhanced computed tomography. By univariate analysis, all of the 9 prognostic factors were associated with AP-related death. A multivariate analysis identified 4 out of the 9 prognostic factors (base excess or shock, renal failure, systemic inflammatory response syndrome criteria, and age) that were associated with AP-related death. Receiver-operating characteristics curve analysis showed that the area under the curve was 0.82 for these 4 prognostic factors and 0.84 for the 9 prognostic factors, suggesting the comparable utility of these 4 factors in the severity assessment. We also examined the temporal changes in treatment strategy for walled-off necrosis in Japan according to the 2003, 2007, and 2011 surveys. Step-up approaches and less-invasive endoscopic therapies were uncommon in 2003 and 2007, but became popular in 2011. Mortality has been decreasing in patients who require intervention for walled-off necrosis. In conclusion, the nationwide survey revealed the comparable utility of 4 prognostic factors in the severity assessment and the increased use of less-invasive, step-up approaches with improved clinical outcomes in the management of walled-off necrosis.

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage

AIM: To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography (EUS)-guided pancreatic fluid collection drainage.

METHODS: A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage (EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections (PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter (electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter (non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups.

RESULTS: There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients (87%) in the electrocautery group and 10 patients (77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100% (15/15) and 100% (13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67% (10/15) and 69% (9/13) for the electrocautery and the non-electrocautery groups, respectively (P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group (mean ± SD: 30 ± 12 min vs 52 ± 20 min, P < 0.001). Adverse events associated with EUS-TD for the treatment of PFCs occurred in 0 patients and 1 patient for the electrocautery and the non-electrocautery groups, respectively (P = 0.942).

CONCLUSION: EUS-TD using an electrocautery dilation catheter as a fistula dilation device for the treatment of symptomatic PFCs appears safe and contributes to a shorter procedure time.

A two-center comparative study of plastic and lumen-apposing large diameter self-expandable metallic stents in endoscopic ultrasound-guided drainage of pancreatic fluid collections

Background and Objectives:

Endoscopic ultrasound-guided drainage of walled-off pancreatic fluid collections (PFCs) (pseudocyst [PC]; walled-off necrosis [WON]) utilizes double pigtail plastic stents (PS) and the newer large diameter fully covered self-expandable stents (FCSEMS) customized for PFC drainage. This study examined the impact of type of stent on clinical outcomes and costs.

Patients and Methods:

Retrospective two-center study. Outcome variables were technical and clinical success, need for repeat procedures, need for direct endoscopic necrosectomy (DEN), and procedure-related costs.

Results:

A total of 49 (PC: 31, WON: 18) patients were analyzed. Initially, PS was used in 37 and FCSEMS in 12. Repeat transmural drainage was required in 14 (PS: 13 [9 treated with PS, 4 treated with FCSEMS]; FCSEMS: 1 [treated with PS]) due to stent migration (PS: 3; FCSEMS: 1) or inadequate drainage (PS: 10). Technical success was 100%. Initial clinical success was 64.9% (25/38) for PS versus 91.7% (11/12) for FCSEMS (P = 0.074). With repeat transmural stenting, final clinical success was achieved in 94.6% and 100%, respectively (P = 0.411). Compared to FCSEMS, PS was associated with greater need for repeat drainage (34.2% vs. 6.3%, P = 0.032). The need for and frequency of DEN was similar between both groups, but PS required more frequent balloon dilatation. PS was significantly cheaper for noninfected PC. Costs were similar for infected PC and WON.

Conclusion:

PS was associated with a higher need for a second drainage procedure to achieve clinical success. The use of FCSEMS did not increase procedural costs for infected PC and WON.

Endoscopic ultrasound-guided drainage of pancreatic pseudocysts

Pancreatic pseudocysts are fluid collections in the peripancreatic tissues associated with acute or chronic pancreatitis. Endoscopic ultrasound (EUS)-guided drainage has become an established indication, having better results as compared to percutaneous drainage, nonguided endoscopic drainage, or surgical drainage. The aim of this review is to assess critically the current literature concerning EUS-guided pseudocyst drainage and to review the place of the procedure in the clinical decision management algorithms of these patients.

Clinical evaluation of endoscopic ultrasonography-guided drainage using a novel flared-type biflanged metal stent for pancreatic fluid collection

Background and Objectives:

Endoscopic ultrasonography (EUS)-guided transluminal drainage for pancreatic fluid collections (PFCs) has become the standard therapy worldwide as a minimally invasive therapy compared with surgical drainage. Recently, a novel flared-type biflanged metal stent (BFMS) designed specifically for the treatment of PFCs has been developed. The aim of this study was to retrospectively assess the feasibility and safety of EUS-guided drainage and direct endoscopic necrosectomy (DEN) for PFCs using the novel flared-type BFMS.

Patients and Methods:

Twenty-one patients were treated by EUS-guided drainage using a flared-type BFMS for PFCs (pancreatic pseudocyst, 2 patients; walled-off necrosis, 19 patients).

Results:

The present study showed a technical success rate of 100%, a final clinical success rate of 100%, a procedure-related adverse event (AE) rate of 0%, an early AE rate of 28.6% (moderate and severe AE rate of 9.5%), a mortality rate of 0%, and a recurrence rate of 9.5%. DEN (mean, 2.3 sessions) was required in 38% of the patients.

Conclusion:

The present study clarified that the EUS-guided drainage using the flared-type BFMS is an effective and safe treatment approach for PFCs. Further studies using randomized controlled multicenter trials are warranted.