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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSION

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

Efficacy of endoscopic ultrasound-guided abscess drainage for non-pancreatic abscesses: A retrospective study

Background and Aim

Percutaneous drainage of intra-abdominal abscesses is often uncomfortable for the patient and may result in prolonged hospital stays. Recent studies have shown that endoscopic ultrasound-guided abscess drainage (EUS-AD) could effectively treat various abscesses and fluid collections. However, no indications or procedures have been established for EUS-AD treatments, and studies on its usefulness and safety are insufficient. The present study aimed to evaluate the efficacy and safety of EUS-AD for treating non-pancreatic abscesses.

Methods

This retrospective study included 20 patients, aged ≥20 years, who underwent EUS-AD for an abscess or fluid accumulation in the abdomen or mediastinum, but not the pancreas. Patients were treated at the Kawasaki University General Medical Center between March 2013 and June 2021. All EUS-AD procedures were performed prior to a percutaneous drainage or surgical drainage.

Results

Among the 20 patients who underwent an EUS-AD for abscess, 8 (40%) had liver abscesses, 6 (30%) had intraperitoneal abscesses, 3 had (15%) splenic abscesses, 1 (5%) had a mediastinal abscess, 1 (5%) had an iliopsoas abscess (n = 1, 5%), and 1 (5%) had an abdominal wall abscess. The technical success rate was 95% (n = 19/20). We inserted nasobiliary catheters in 4/20 patients (20%). The clinical success rate was 90% (n = 18/20). Two clinical failures required reintervention, and both were treated with percutaneous drainage. Adverse events were observed in 2/20 patients (10%). One patient experienced fever after the procedure, and the other experienced localized peritonitis.

Conclusion

EUS-AD was effective and safe for abscess removal, particularly when approached from the upper gastrointestinal tract.

A Comparison of the Efficacy of Plastic Stent Placement Above and Across the Sphincter of Oddi for Benign Biliary Hilar Stricture

We investigated the efficacy and safety of endoscopic plastic stent (PS) placement for hilar benign biliary strictures (BBSs) and compared cases with PS placement above (inside stent, IS) and across (usual stent, US) the sphincter of Oddi. Patients who underwent initial endoscopic PS placement for hilar BBSs between August 2012 and December 2021 were retrospectively analyzed. Hilar BBSs in 88 patients were investigated. Clinical success was achieved in 81 of these cases (92.0%), including 38 patients in the IS group and 43 patients in the US group. Unexpected stent exchange (uSE) before the first scheduled PS exchange occurred in 18 cases (22.2%). The median time from first stent placement to uSE was 35 days. There was no significant difference in the rate and median time to uSE between the two groups. The rates of adverse events such as pancreatitis or cholangitis in the two groups did not significantly differ. However, the rate of difficult stent removal in the IS group (15.8%) was significantly higher than that in the US group (0%) (p=0.0019). US placement is preferable to IS placement for scheduled stent exchange, as it offers the same effectiveness and risk of adverse events with easier stent removal.

Fully covered metallic stents for anastomotic biliary strictures after living donor liver transplantation

Objectives

Anastomotic biliary strictures (ABSs) are common complications following living donor liver transplantation (LDLT). We evaluated the feasibility of a novel removable, intraductal, fully covered, self‐expandable metallic stent (FCSEMS) for the treatment of ABSs following LDLT.

Methods

Nine patients with duct‐to‐duct ABSs that developed following LDLT were prospectively enrolled in this study. We placed a short FCSEMS with a long lasso and middle waist formation in each patient's ABS above the papilla and removed it 16 weeks later.

Results

The FCSEMS placements were successful in all nine cases. Four patients experienced mild cholangitis, which was resolved with conservative treatment. Additionally, there was one case of distal migration. The FCSEMSs were successfully removed from all the patients, and the clinical success rate was 100%. Stricture recurrence occurred in one (11.1%) patient during the follow‐up period.

Limitations

The small number and lack of comparison with other types of FCSEMSs and plastic stents.

Conclusions

Intraductal placement of FCSEMSs is useful for treating refractory ABSs after LDLT, although further studies are required with larger sample sizes.

Endoscopic Ultrasound-Guided Gallbladder Drainage versus Percutaneous Gallbladder Drainage for Acute Cholecystitis: A Systematic Review and Meta-Analysis

Background: Percutaneous transhepatic gallbladder drainage (PT-GBD) has been the treatment of choice for acute cholecystitis patients who are not suitable for surgery. The effectiveness of endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) as an alternative to PT-GBD is not clear. In this meta-analysis, we have compared their efficacy and adverse events. Methods: We adhered to the PRISMA statement to conduct this meta-analysis. Online databases were searched for studies that compared EUS-GBD and PT-GBD for acute cholecystitis. The primary outcomes of interest were technical success, clinical success, and adverse events. The pooled odds ratio (OR) with a 95% confidence interval (CI) was calculated using the random-effects model. Results: A total of 396 articles were screened, and 11 eligible studies were identified. There were 1136 patients, of which 57.5% were male, 477 (mean age 73.33 ± 11.28 years) underwent EUS-GBD, and 698 (mean age 73.77 ± 8.7 years) underwent PT-GBD. EUS-GBD had significantly better technical success (OR 0.40; 95% CI 0.17-0.94; p = 0.04), fewer adverse events (OR 0.35; 95% CI 0.21-0.61; p = 0.00), and lower reintervention rates (OR 0.18; 95% CI 0.05-0.57; p = 0.00) than PT-GBD. No difference in clinical success (OR 1.34; 95% CI 0.65-2.79; p = 0.42), readmission rate (OR 0.34; 95% CI 0.08-1.54; p = 0.16), or mortality rate (OR 0.73; 95% CI 0.30-1.80; p = 0.50) was noted. There was low heterogeneity (I² = 0) among the studies. Egger's test showed no significant publication bias (p = 0.595). Conclusion: EUS-GBD can be a safe and effective alternative to PT-GBD for treating acute cholecystitis in non-surgical patients and has fewer adverse events and a lower reintervention rate than PT-GBD.

Placement of Plastic Stents after Direct Endoscopic Necrosectomy through a Novel Lumen-Apposing Metal Stent for Effective Treatment of Laterally Extended Walled-Off Necrosis: A Pilot Study

Direct endoscopic necrosectomy (DEN) using a lumen-apposing metal stent (LAMS) is a standard therapy for the management of symptomatic walled-off necrosis (WON). Here, we demonstrated the efficacy of the routine placement of long plastic stents after a DEN session to treat laterally extended WON. Patients (n = 6) with symptomatic laterally extended WON who underwent DEN after long plastic stent placement were included. The primary endpoint was clinical efficacy of the procedure. The technical and clinical success rates were 100% without major adverse events. The WON extended to the pelvic cavity or pericolic area, and the WON size was between 18.6 and 35.8 cm in length. The median number of DEN sessions was 10 (range 6-16), and two or three long plastic stents were placed after every DEN session. Only one patient suffered from pneumoperitoneum during DEN, which spontaneously resolved within 20 min. Placement of a long plastic stent after DEN using LAMS is a minimally invasive and effective treatment for symptomatic laterally extended WON. Further studies are needed to define the indications and most suitable patients.

Prevention of pancreatitis after stent implantation for distal malignant biliary strictures: systematic review and meta-analysis

INTRODUCTION

Biliary stent placement remains a palliative treatment for patients with unresectable distal malignant biliary strictures (DMBS). The incidence of post-ERCP-pancreatitis (PEP) significantly increases in patients receiving fully covered self-expandable metal stents (FCSEMS) who undergo endoscopic retrograde cholangiopancreatography (ERCP).

AREAS COVERED

This review provides an overview of prevention of PEP after stent implantation for DMBSs. The following operational variables were evaluated: (1) stent type (plastic or metal stent); (2) stent location (above or across the sphincter of Oddi); (3) prophylactic pancreatic duct stent placement; (4) endoscopic sphincterotomy (EST). PubMed, EMBASE, and Cochrane database were searched to identify eligible studies up to October 2021. The odds ratio (OR) with 95% confidence intervals (CI) were pooled using fixed- or random- effects models.

EXPERT OPINION

1. PEP occurs more frequently in DMBS patients with self-expandable metal stents (SEMS) compared to that plastic stent (PS). 2. The PEP incidence is higher in covered stents than that in uncovered self-expandable metal stents (USEMS), but not significantly. 3. PEP incidence increases in patients receiving transpapillary FCSEMS placement, particularly when there is an absence of pancreatic duct dilation, and prophylactic pancreatic stenting is recommended for these patients. 4. Limited studies with small sample indicate that there is no significant difference in PEP incidence between transpapillary and suprapapillary stents placement for DMBS. 5. Limited studies indicate that EST does not significantly affect the incidence of pancreatitis in DMBS patients.

Covered self-expandable metal stents versus plastic stents for preoperative biliary drainage in patient receiving neo-adjuvant chemotherapy for borderline resectable pancreatic cancer: Prospective randomized study

OBJECTIVES

This single-center comparative randomized superiority study compared biliary stenting using fully covered self-expandable metal stents (FCSEMS) and biliary stenting using plastic stents (PS) in preoperative biliary drainage of patients with borderline resectable pancreatic cancer (BRPC) who are planned to undergo a single regimen of neo-adjuvant chemotherapy (NAC).

METHODS

Twenty-two patients with BRPC who required preoperative biliary drainage before NAC (Gemcitabine plus Nab-paclitaxel) were randomly assigned 1:1 to the FCSEMS or PS group. The primary endpoint was the rate of stent dysfunction until surgery or tumor progression. Secondary endpoints were stent patency, number of re-interventions, adverse events of endoscopic retrograde biliary drainage (EBD), operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs.

RESULTS

Eleven patients in each of the groups reached the primary endpoint. The FCSEMS group showed a significantly lower rate of stent dysfunction (18.2% vs. 72.8%, P = 0.015), longer stent patency (P = 0.02), and lower number of re-interventions for stent dysfunction (0.27 ± 0.65 vs. 1.27 ± 1.1, P = 0.001) than the PS group. The adverse events of EBD, operation time, volume of intraoperative bleeding, postoperative hospitalization, postoperative adverse events and medical costs did not significantly differ between the two groups.

CONCLUSIONS

In patients with BRPC for preoperative biliary drainage, stent dysfunction occurred less frequently with FCSEMSs than with PSs. In addition, FCSEMS and PS provided similar preoperative management of BRPC in terms of the safety of surgery and medical costs. (UMIN ID000030473).

Uncovered versus covered metallic stents for the management of unresectable malignant distal biliary obstruction: a randomized multicenter trial

OBJECTIVE

The treatment result of the uncovered metallic stent (uncovered MS) and covered metallic stent (covered MS) for unresectable malignant distal biliary obstruction is controversial. This time, we conducted this study to compare the efficacies and complication rates of uncovered MS and covered MS in unresectable malignant distal biliary obstructions at a prospective randomized multicenter trial.

MATERIALS AND METHODS

From April 2014 to September 2018, patients with unresectable malignant distal biliary obstruction were randomly assigned to 2 groups: the uncovered MS group and the covered MS group.

RESULTS

92 treatment results patients were discussed. 48 patients were assigned to the uncovered MS group and 44 cases were assigned to the covered MS group. Both groups showed a drainage effect. No significant difference was found in the drainage effect between the 2 groups. The number of stent occlusion was significantly greater (p = .0467) in uncovered MS (43.8%) comparing with those in covered MS (22.7%). As the cause of stent occlusion, tumor ingrowth was significantly greater (p < .001) in the uncovered MS group (35.4%) than in the covered MS group (2.3%). The median stent patency period was significantly longer (p = .0112) in the covered MS group (455 days) than that of the uncovered MS group (301 days). A significant difference in the median survival period was not found between the 2 groups.

CONCLUSIONS

Covered MS showed the possibility of extending the stent patency period by suppressing tumor ingrowth more than uncovered MS does. The UMIN Clinical Trial Registry number is UMIN000015093.

Usefulness of the Novel Snare-over-the-Guidewire Method for Transpapillary Plastic Stent Replacement (with Video)

Unsuccessful stent replacement in transpapillary biliary drainage with plastic stents (PSs) has a significant impact on patient prognosis; thus, a safe and reliable replacement method is required. We aimed to compare the snare-over-the-guidewire (SOG) method, wherein the PS lumen is used as an access route to the biliary tract and the PS is removed with a snare inserted via the inserted guidewire, with the conventional side-of-stent (SOS) method, wherein the biliary approach is performed from the side of the PS. This retrospective single-center study included 244 consecutive patients who underwent biliary PS replacement between January 2018 and July 2020. The procedural success rates were compared between the two methods. A predictive analysis of unsuccessful PS replacement was also performed. The procedural success rate in the SOG group was significantly higher than that in the SOS group (p = 0.026). In the proximal biliary stenosis lesion, the same trend was observed (p = 0.025). Multivariate analysis also showed that the SOS method (p = 0.0038), the presence of proximal biliary stenosis (p < 0.0001), and parapapillary diverticulum (p = 0.0007) were predictors of unsuccessful PS replacement. The SOG method may be useful for biliary PS replacement, especially in cases of proximal hilar bile duct stenosis.

Comparison of metal stents versus plastic stents for preoperative biliary drainage: a meta-analysis of five randomized controlled trials

BACKGROUND

Although routine preoperative biliary drainage (PBD) is generally not recommended for patients with malignant distal biliary obstruction (MDBO), it is still necessary in many cases. The objective of this study is to compare the effects of metal stents (MSs) and plastic stents (PSs) on PBD in patients with MDBO.

METHODS

All the randomized controlled trials (RCTs) that compared MS with PS for PBD and published from the date of database establishment to September 2020 were identified by searching the PubMed, EMBASE and Cochrane databases.

RESULTS

Five RCTs involving 445 patients were included. There were 201 cases in the MS group, with 244 in the PS group. Re-interventions (relative risk (RR) = 0.40, 95% confidence interval (CI) 0.21-0.75, P = 0.004), stent occlusions (RR = 0.36, 95% CI 0.18-0.75, P = 0.006), postoperative complications (RR = 0.76, 95% CI 0.59-0.97, P = 0.03) and preoperative cholangitis (RR = 0.19, 95% CI 0.05-0.78, P = 0.02) were lower in the MS group than in the PS group. Preoperative pancreatitis (RR = 2.11, 95% CI 1.06-4.19, P = 0.03) was higher in the MS group than in the PS group. No significant difference was observed in the overall preoperative complications, postoperative pancreatic fistulas, delayed gastric emptying, wound infections and postoperative bleeding between these two groups.

CONCLUSIONS

MS and PS exerted a similar effect on PBD, but PS had a higher risk of preoperative stent obstruction and postoperative complications, requiring more frequent interventions preoperatively. However, larger sample and higher quality RCTs are necessary for further verification.

Comparative Efficacy of Various Stents for Palliation in Patients with Malignant Extrahepatic Biliary Obstruction: A Systematic Review and Network Meta-Analysis

Although many studies have investigated the efficacy of stent placement for patients with malignant extrahepatic biliary obstruction, the clinical outcomes and adverse events of biliary stenting have not been comprehensively evaluated. We searched all relevant randomized-controlled trials that evaluated the comparative efficacy of biliary stents, including the plastic stents, uncovered self-expandable metal stents (SEMSs), and covered SEMSs in patients with malignant extrahepatic biliary obstructions. Twenty-one studies with 2326 patients were included. Both uncovered and covered SEMSs had a lower risk of recurrent biliary obstruction (RBO) compared to plastic stents (risk ratio (RR) (95% confidence interval [CI]): uncovered vs. plastic, 0.46 (0.35–0.62); covered vs. plastic, 0.46 (0.34–0.62)). A comparison of the groups using SEMSs revealed that tumor ingrowth was common in the uncovered SEMS group, while stent migration, tumor overgrowth, and occlusion by sludge were common in the covered SEMS group; however, the overall risk of RBO did not differ between these groups (RR (95% CI): uncovered vs. covered: 1.02 (0.80–1.30)). Although the main causes of RBO vary across stents, RBO risk was similar between uncovered and covered SEMS groups. Both SEMSs have superior efficacy in terms of RBO compared to plastic stents.

Urgent and early EUS-guided biliary drainage in patients with acute cholangitis

Background and Objectives:

EUS-guided biliary drainage (EUS-BD) has been reported as an effective alternative drainage technique. However, clinical data on EUS-BD for patients with acute cholangitis (AC) are limited. The aim of this study was to analyze the clinical outcomes of EUS-BD in patients with AC.

Patients and Methods:

Nineteen patients with AC who underwent urgent or early drainage (within 96 h) by EUS-guided hepaticoenterostomy (EUS-HES) between January 2014 and November 2019 were retrospectively reviewed. Furthermore, the clinical outcomes of EUS-HES using a plastic stent in the AC group (n = 15) were compared to those in the non-AC group (n = 88).

Results:

In the 19 AC cases, the technical and clinical success rate was 100% with 5.3% of moderate adverse events (biliary peritonitis [n = 1]). Regarding the comparison between the AC group and the non-AC group, the clinical success rate was 100% in both groups and the adverse event rate was not statistically significantly different (P = 0.88). Although the recurrent biliary obstruction (RBO) rate was not statistically significantly different (P = 0.43), the early RBO rate was statistically significantly higher in the AC group (26.7% vs. 3.4%, P < 0.001). Kaplan–Meier curves showed that AC was associated with a shorter time to RBO (P = 0.046). The presence of AC was found to be an independent risk factor of early RBO (odds ratio = 10.3; P = 0.005).

Conclusions:

Urgent or early biliary drainage (within 96 h) by EUS-BD can be a feasible and safe alternative procedure for patients with AC, although there is a tendency of early RBO.

The placement of multiple plastic stents still has important roles in candidates for chemotherapy for unresectable perihilar cholangiocarcinoma

BACKGROUND/PURPOSE

Placement of uncovered self-expandable metallic stents (U-SEMSs) of patients with unresectable perihilar cholangiocarcinoma (UPHC) is recommended as the treatment of first choice to address bile stasis. The aim of this study was to determine which of the following two endoscopic stents might be the stent of first choice for the treatment of biliary stasis in patients with UPHC: plastic stents (PSs) or U-SEMSs.

METHODS

U-SEMSs, deployed as a stent-in-stent, were selected as the stents of first choice from 2013 and 2014, while PSs began to be selected as the stents of first choice from 2015 onward.

RESULTS

The median time to recurrent biliary obstruction were 66 days in the PS group (N = 38) and 105 days in the U-SEMS group (N = 37; P = .04). Emergency endoscopy was necessitated in 76.3% (29/38) of patients of the PS group and 54.1% (20/37) of patients of the U-SEMS group (P = .0434). The success rate of the first reintervention was 96.5% (27/29) in the PS group and 55% (11/20) in the U-SEMS group (P = .0002). Sustainable chemotherapy could be carried out in 55.2% of patients in the PS group and 32.4% of patients in the U-SEMS group (P = .0472). Multivariate analysis identified selection of U-SEMS as the stent of first choice as the only independent factor predictive of successful reintervention (P = .0016, odds ratio = 0.058). However, the stent selection was not an independent factor for feasible chemotherapy.

CONCLUSIONS

Plastic stent placement could enhance the success rate of reintervention in patients with UPHC and might be facilitated by sustainable chemotherapy. However, stent selection might not have an influence on the prognosis.

[Mechanisms and prevention of biliary stent occlusion]

One of significant achievements of modern endoscopy is development of retrograde biliary stenting for obstructive jaundice. This method ensured widespread application of endoscopic decompression in the treatment of patients with malignant biliary obstruction as preparation before radical surgery and final palliative care. Endoscopic retrograde transpapillary stenting firmly took its place together with antegrade and percutaneous stenting. There are certain advantages of this technique including minimally invasiveness and favorable quality of life. However, this approach is associated with some drawbacks associated with stent occlusion and difficult correction of this complication. The maximum diameter of the plastic stent (PS) is determined by the width of the working channel of the duodenoscope. In this regard, self-expandable metal stents (SEMS) were developed to increase the diameter of bile drainage channel. SEMS are associated with prolonged function. However, there is another problem. It is a germination of SEMS followed by impossible removal of the stent for its subsequent replacement. A further step in development of endoscopic biliary stents was the use of special SEMS coating to exclude tumor or granulation ingrowth. The problem of biliary stent occlusion remains relevant despite some improvement of stenting results. Mechanisms of occlusion of biliary stents and prevention of these events are discussed in this review.

Is complete stone removal for choledocholithiasis always necessary in extremely elderly patients?

BACKGROUND AND AIM

Endoscopic stone removal has some complications. Although the life expectancy of elderly patients has increased dramatically worldwide, little information is available on the necessity of complete endoscopic stone removal in extremely elderly patients. This study aimed to evaluate the safety and efficacy of complete endoscopic stone removal in extremely elderly patients.

METHODS

All extremely elderly patients (>90 years) who underwent endoscopic stone removal for choledocholithiasis at our hospital between January 2012 and January 2017 were retrospectively evaluated. The included patients were divided into complete stone removal and incomplete stone removal groups. Complication rate, overall survival (OS), and disease-specific survival (DSS) rates were compared between the two groups.

RESULTS

Overall, 73 patients were included in this study. The median number of stones was one (range, 0-10) and two (range, 1-12) (P = 0.043), while the median diameter of the largest stones was 9 (range, 0-27) and 14 (range, 5-46) mm (P = 0.001) in the complete and incomplete stone removal groups, respectively. During the follow-up period, OS was 60% and 39% and DSS was 95% and 97% in the complete and incomplete stone removal groups, respectively. Kaplan-Meier analysis found no significant difference in OS and DSS between the two groups (P = 0.052 and P = 0.646, respectively).

CONCLUSION

Complete stone removal might not always be necessary in extremely elderly patients aged ≥90 years.

Fully covered self-expandable metal stent with an anti-migration system vs plastic stent for distal biliary obstruction caused by borderline resectable pancreatic cancer: A protocol for systematic review

BACKGROUND AND AIM

Biliary obstruction can impair the effectiveness of neo-adjuvant chemotherapy. This study was designed to compare biliary stenting with covered self-expandable metal stents (FCSEMS) and plastic stents (PS) in patients with biliary obstruction caused by borderline resectable pancreatic cancer (BRPC) who were undergoing neo-adjuvant chemotherapy during preoperative biliary drainage.

METHODS

This single-center, comparative, randomized, superiority study was designed to compare FCSEMS with PS for drainage of biliary obstruction of BRPC. Twenty two eligible patients providing informed consent will be randomized 1:1 by computer to either FCSEMS or PS for endoscopic retrograde biliary drainage (ERBD). All subsequent clinical interventions, including crossover to alternative procedures, will be at the discretion of the treating physician based on standard clinical care. The primary outcomes will be the rates and causes of stent dysfunction during preoperative biliary drainage. Other outcomes include time required for ERBD, adverse events related to ERBD, period from ERBD to surgery, percentage of patients able to undergo surgery, operation time, intraoperative bleeding volume, postoperative adverse events, and postoperative hospitalization. Subjects, treating clinicians, and outcome assessors will not be blinded to assignment.

DISCUSSION

This study is intended to determine whether FCSEMS or PS is the better biliary stent for ERBD for management of patients with biliary obstruction of BRPC, a common clinical dilemma that has not yet been investigated in randomized trials.

TRIALS REGISTRATION

UMIN-CTR, Identifier: UMIN000030473. Registered July 10, 2017, Wakayama Medical University Hospital.

Radical treatment for walled-off necrosis: Transmural nasocyst continuous irrigation

BACKGROUND AND AIM

Treatment efficiency of walled-off necrosis (WON) using endoscopic ultrasound-guided drainage (EUS-D) with a double pigtail stent (DPS) is limited. Endoscopic necrosectomy is often carried out if EUS-D fails. However, endoscopic necrosectomy is associated with significant morbidity and mortality. Thus, we developed transmural nasocyst continuous irrigation (TNCCI) as an alternative therapeutic option for WON. This study aimed to evaluate the usefulness of TNCCI therapy for WON.

METHODS

Between April 2009 and March 2018, 19 of 39 patients admitted with WON underwent EUS-D. Ten consecutive patients also received TNCCI therapy (TNCCI group) between May 2015 and March 2018. TNCCI was carried out by inserting an external tube from the gastroduodenal lumen into the WON under endoscopic ultrasonography guidance and then continuously irrigating the WON with saline at a rate of 40 ml/h. Nine consecutive patients who underwent EUS-D without TNCCI therapy between April 2009 and April 2015 were used for comparison (control group). Various parameters were compared between the TNCCI and control groups.

RESULTS

Time taken to reduce WON (6 vs 32 days, P = 0.001), implementation rate of endoscopic necrosectomy (0% vs 55.6%, P = 0.01), and number of endoscopic necrosectomy sessions per patient (0 vs 0.8 ± 1.0, P = 0.008) were significantly lower in the TNCCI group than in the control group.

CONCLUSIONS

Walled-off necrosis can be effectively and safely treated by endoscopic drainage with a DPS and TNCCI. This technique can be an alternative therapeutic option before carrying out endoscopic necrosectomy.

Multiple plastic versus fully covered metal stents for managing post-liver transplantation anastomotic biliary strictures: a meta-analysis of randomized controlled trials

Background

Anastomotic biliary strictures (ABS) following liver transplantation (LT) are one of the most common complications, occurring in 4.5-32% of patients. Multiple plastic stenting (MPS) requires multiple sessions, with the associated risk, cost and patient discomfort. Fully covered self-expandable metal stents (FC-SEMS) have increasingly been used in this setting. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs), comparing the role of FC-SEMS and MPS in the treatment of ABS post-LT.

Methods

We conducted a bibliographic search using PubMed and EMBASE, aimed at identifying available RCTs that compared MPS to FC-SEMS in patients with ABS post LT from January 2000 to October 2017. Primary outcomes were ABS resolution and recurrence, while secondary outcomes were adverse events and number of procedures performed. Pooled estimates were calculated using random-effects models.

Results

Four RCTs (205 patients) were included. ABS resolution and recurrence did not differ significantly between the groups (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.43-2.56, P=0.92; and OR 2.37, 95%CI 0.54-10.38, P=0.25). The same was true for adverse events (OR 0.91, 95%CI 0.84-3.48, P=0.86) and migration rate (OR 1.31, 95%CI 0.46-3.71, P=0.61). The mean number of endoscopic retrograde cholangiopancreatography procedures was lower for FC-SEMS (mean difference [MD] -2.08).

Conclusions

FC-SEMS and MPS had equal ABS resolution and recurrence, although there was a trend towards a higher recurrence rate in FC-SEMS that disappeared when trials with a shorter stent indwelling time were excluding. No difference was found in overall adverse events or migration rate.

Benign biliary strictures: prevalence, impact, and management strategies

Benign biliary strictures (BBSs) may form from chronic inflammatory pancreaticobiliary pathologies, postoperative bile-duct injury, or at biliary anastomoses following liver transplantation. Treatment aims to relieve symptoms of biliary obstruction, maintain long-term drainage, and preserve liver function. Endoscopic therapy, including stricture dilatation and stenting, is effective in most cases and the first-line treatment of BBS. Radiological and surgical therapies are reserved for patients whose strictures are refractory to endoscopic interventions. Response to treatment is dependent upon the technique and accessories used, as well as stricture etiology. In this review, we discuss the various BBS etiologies and their management strategies.

Comparison of Metal and Plastic Stents for Preoperative Biliary Drainage in Resectable and Borderline Resectable Periampullary Cancer: A Meta-Analysis and System Review

AIM

The aim of this study was to compare the plastic stents with metal stents for preoperative biliary drainage (PBD) in terms of the rate of endoscopic reintervention and PBD-related pre- and postoperative complications in patients with resectable and borderline resectable periampullary cancer.

METHODS

We conducted a comprehensive search of the PubMed, EMBASE, and the Cochrane Library database to identify relevant available articles from their inception to September 2017. The odds ratio (OR) with 95% confidence interval (CI) was calculated to compare the incidence of endoscopic reintervention and stent-related complications between the plastic and metal stents groups. Also, we used RevMan 5.3 to perform the pooled analyses.

RESULTS

Four trials (three randomized controlled trials [RCT] and one prospective clinical trial) with 392 patients were included. One hundred seventy-four patients received metal stents for PBD, and 218 patients received plastic stents. The metal stents group had a significant lower rate of endoscopic reintervention (OR = 0.30, 95% CI = 0.13-0.73, P = .008) and preoperative cholangitis (OR = 3.60, 95% CI = 1.62-7.98, P = .002) compared with the plastic stents group. But there was a significantly higher rate of PBD-related pancreatitis (OR = 3.60, 95% CI = 1.62-7.98, P = .002) in the metal stents group.

CONCLUSIONS

The present meta-analysis revealed that metal stents have significantly lower rate of reintervention and cholangitis than plastic stents. But plastic stents have an obvious superiority over metal stents in terms of the incidence of preoperative pancreatitis. More RCTs are required to support this conclusion and provide more detailed information about the complications and treatment. Meanwhile, a uniform standard for the PBD is required in patients with malignant distal biliary obstruction.

Experimental study on the friction effect of plastic stents for biliary stone fragmentation (with video)

BACKGROUND AND AIM

In patients with irretrievable or intractable bile duct stone, temporary insertion of a plastic stent (PS) followed by further endoscopic retrograde cholangiopancreatography (ERCP) or surgery has been recommended as a 'bridge' therapy. However, the exact mechanism of stone fragmentation has not been discovered. The aim of the present study was to evaluate whether PS shape can facilitate stone fragmentation.

METHODS

Using a new in vitro bile flow phantom model, we compared the friction effect among three different PS groups (straight PS group, double pigtail-shaped PS group, and screw-shaped PS group) and a control group. Each group had 10 silicon tube blocks that separately contained one stone and two PS. The control group had 10 blocks each with only a stone and no PS. We carried out analysis of the friction effect by stone weight and volume changes among the groups, excluding fragmented stones.

RESULTS

After 8 weeks, complete fragmentation was noted in one out of 34 cholesterol stones (2.9%) and in four out of six pigmented stones (66.7%). Fragmentation tended to be more prominent in the screw-shaped PS group than in the straight PS group, double pigtail-shaped group, and control group (volume change: -11.33%, 7.94%, 4.43%, and 2.05%, respectively, P = 0.1390; weight change: -9.30%, 0.71%, -0.10%, and -1.23%, respectively, P = 0.3553).

CONCLUSION

Stone fragmentation may be induced by PS friction effect. Also, screw-shaped plastic stents may improve friction effect. These results may help guide future PS development and clinical decisions.

Recurrent Bleeding from a Hepatic Artery Pseudoaneurysm after Biliary Stent Placement

A 78-year-old woman was admitted with benign biliary stenosis. A plastic stent was placed at the left branch to prevent obstructive cholangitis. Two weeks after the procedure, the patient was readmitted with cholangitis caused by hemobilia. However, computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), peroral cholangioscopy, and abdominal angiography failed to establish the bleeding source. At the seventh bleeding, CT revealed a hepatic artery pseudoaneurysm for which coil embolization was successfully performed. Hemobilia after plastic stent placement is extremely rare. We urge clinicians to consider the possibility of a pseudoaneurysm near the stent when trying to identify the bleeding source.

Outcomes of preoperative biliary drainage from a single tertiary center: Is there still a role for plastic stents?

OBJECTIVES

Preoperative biliary drainage (PBD) can relieve symptoms of cholestasis, but carries risk of procedural complications. Metal stents have wider lumens and longer patency, although plastic stents (PS) remain in use. We reviewed the outcomes after PBD in patients with cholestasis.

METHODS

Patients with symptomatic cholestasis who were likely to wait for over 2 weeks before surgery and were thus treated with PBD between January 2011 and May 2015 were included. Patients were evaluated for stenting-related complications, time interval to surgery, resection rate, improvement in bilirubin level and surgical complications.

RESULTS

Forty patients underwent PBD by endoscopic retrograde cholangiopancreatography (ERCP). Of these, 36 patients received the placement of PS, one received a metal stent and the remaining three required percutaneous drainage due to unsuccessful biliary cannulation. Serum bilirubin declined from 172 μmol/L (baseline) to 14 μmol/L at 30 days (P < 0.0001). Median time interval from ERCP to surgery in all patients was 5 weeks (range 2-36 weeks). Preoperative stenting-related complications occurred in seven patients after a median of 3 weeks (range 1-6 weeks). Median time to surgery was similar in patients with and without stenting-related complications (5 weeks vs 4 weeks, respectively, P = 0.33). Surgery was completed in 32 (80%) patients, with a post-Whipple complication rate of 53%.

CONCLUSIONS

PBD using mostly PS was effective in reducing bilirubin levels and did not detrimentally affect time interval to surgery. Median time interval to stenting-related complication occurred after 3 weeks, suggesting PS may be most useful for short-term PBD.

Metal versus plastic stents for unresectable gallbladder cancer with hilar duct obstruction

BACKGROUND AND AIM

Metal stents usually have a longer stent patency than plastic stents for malignant biliary obstruction. However, stent patency and patient survival may differ depending on the causative disease and stent type. There are no data regarding the selection of stents for unresectable gallbladder cancer (GC) with hilar duct obstruction. The aim of the present study was to evaluate the efficacy of metal versus plastic stents for unresectable GC with hilar duct obstruction.

METHODS

Fifty-nine unresectable GC patients with jaundice were divided into metal stent group (MSG) and plastic stent group (PSG) depending on stent deployment. Clinical outcomes and approximate costs were assessed retrospectively.

RESULTS

No significant difference was found between MSG (n = 28) and PSG (n = 31) for clinical success, early adverse events and later cholangitis. Median patency and survival were 119 and 112 days in MSG versus 93 and 118 days in PSG, respectively (P > 0.05). However, the overall cost was higher in MSG than in PSG (P = 0.00). Cox proportional hazards model analysis showed that the lower Bismuth type was associated with a longer stent patency (P = 0.046), whereas older age (P = 0.041) and lower TNM stage (P = 0.002) were associated with longer survival.

CONCLUSION

Although metal and plastic stents have similar clinical efficacy, it seems reasonable to choose plastic stents as the treatment of choice for unresectable GC when cost-effectiveness is taken into account.

Lumen-apposing metal stents for drainage of pancreatic fluid collections: When and for whom?

BACKGROUND AND AIM

Although lumen-apposing metal stents (LAMS) are increasingly being used for drainage of pancreatic fluid collections (PFC), their advantage over plastic stents is unclear.

METHODS

In this retrospective case-control study, 20 patients who underwent PFC drainage using LAMS were matched with 40 patients treated with plastic stents according to PFC type (walled-off necrosis [WON] vs pseudocyst) and procedural technique (conventional vs multi-gate). Main outcome measures were treatment success, reintervention, clinical and stent-related adverse events, procedural duration, length of hospital stay (LOS) and hospital costs.

RESULTS

At median follow up of 570 days, except for median procedural duration (8.5 vs 25 min, P < 0.001), there was no significant difference in treatment success (95.0 vs 92.5%, P = 0.99), reintervention (25.0 vs 30.0 %, P = 0.77), clinical (10.0 vs 12.5 %, P = 0.99) and stent-related adverse events (10.0 vs 2.5 %, P = 0.26) or median LOS (2 [IQR 1-5] vs 2 [IQR 1-7] days, P = 0.58) between patients treated with LAMS versus plastic stents. Although there was no difference for WON ($16 708 for LAMS vs $17 221 for plastic stents, P = 0.90), mean hospital costs were significantly lower for pseudocysts using plastic stents ($18 996 vs $58 649, P = 0.03).

CONCLUSIONS

Although there is no difference in clinical outcomes, treating pseudocysts using plastic stents is less expensive. It is also possible that the short procedural duration is a surrogate marker for procedural complexity and this may drive the use of LAMS in sicker patients.

Efficacy of metal and plastic stents for transmural drainage of pancreatic fluid collections: a systematic review

BACKGROUND AND AIM

Metal stents are being used more frequently for transmural endoscopic drainage of pancreatic fluid collections (PFC) despite lack of data. The present systematic review was conducted to compare the rates of treatment success, adverse events and recurrence between patients undergoing metal versus plastic stent placement for endoscopic transmural drainage of PFC.

METHODS

MEDLINE and EMBASE were searched to identify all published manuscripts that evaluated metal stents for endoscopic transmural drainage of PFC. All published studies from the same period involving plastic stent placement for PFC drainage that included >50 patients were also identified. Main outcome measures were to compare the rates of treatment success, adverse events and recurrence between the metal and plastic stent cohorts.

RESULTS

Seventeen studies (881 patients) met inclusion criteria. There was no difference in overall treatment success between patients treated with plastic and metal stents (81% [95% CI, 77-84%] vs 82% [95% CI, 74-88%]) for both pseudocysts (85% [95% CI, 81-89%] vs 83% [95% CI, 74-89%]) and walled-off necrosis (70% [95% CI, 62-76%] vs 78% [95% CI, 50-93%]). Also, there was no difference in the rates of adverse events (16% [95% CI, 14-39%] vs 23% [95% CI, 16-33%]) or recurrence (10% [95% CI, 8-13%] vs 9% [95% CI, 4-19%]) between plastic and metal stents.

CONCLUSIONS

Current evidence does not support routine placement of metal stents for transmural drainage of PFC. Randomized trials are needed to justify the use of metal stents for PFC drainage.

Novel biliary self-expanding metal stents: indications and applications

Endoscopic insertion of a self-expanding metal stent (SEMS) through a malignant common bile duct stricture is the first line of palliation for malignant jaundice. Patency of these stents remains a major concern. SEMS dysfunction can result from tumor ingrowth, overgrowth and/or clogging. Initial SEMS modifications involved covering the central part of the stent in order to reduce ingrowth and ultimately increase patency. Fully covered stents became available shortly after reports of their use in human patients. The potential removability and radial strength of SEMS have led to evaluation of their use in new indications including benign biliary strictures, post sphincterotomy bleeding and perforation. Other aspects of development include the addition of features such as anti-reflux valves, drug elution and spontaneous biodegradability. These aspects and their clinical implications are reviewed and discussed.

Percutaneous transhepatic hybrid biliary endoprostheses using both plastic and metallic stents for palliative treatment of malignant common bile duct obstruction

To evaluate clinical safety and efficacy of percutaneous transhepatic hybrid biliary prostheses for palliative treatment in patients with common bile duct obstruction caused by advanced malignancies. A total of 13 consecutive patients was treated with percutaneous transhepatic biliary endoprostheses concurrently using both plastic and metallic stents. Serum total bilirubin levels before and after stent placement were evaluated. The technical success rate, the period with no obstructive jaundice, patient survival and complications were also assessed. Median bilirubin levels decreased from 3.8 mg/dL before to 1.2 mg/dL after stent placement, and this difference was statistically significant. The median no-jaundice period after bile duct stent placement was 6.0 months (range: 2-11 months), and overall survival time was 7.0 months. Of the 13 patients, nine did not have recurrent jaundice by the time of death, whereas four (31%) had recurrent jaundice. A second intervention was performed in these four patients. A new plastic stent was placed and jaundice did not recur up to the time of death. No serious complications such as cholangitis, pancreatitis or bile duct perforation developed. Percutaneous transhepatic hybrid biliary endoprostheses using both plastic and metallic stents can be useful as non-invasive palliative treatment to relieve jaundice in patients with malignant obstructive jaundice.

Percutaneous placement of a biliary plastic stent

Endoscopic biliary plastic stent placement is a well-established technique for unresectable and recurrent biliary obstructive disease and provides significant improvement in the quality of life. We describe a new technique of percutaneous placement of biliary plastic stent that has not been previously mentioned in the literature.