No benefit of endoscopic sphincterotomy before biliary placement of self-expandable metal stents for unresectable pancreatic cancer

Fully covered versus partially covered self-expandable metal stents for palliation of distal malignant biliary obstruction: a systematic review and meta-analysis

BACKGROUND AND AIMS

Self-expandable metal stents (SEMSs) are standardly used for distal malignant biliary obstruction (dMBO). Although data suggest that covered versus uncovered SEMSs increase the time to recurrent biliary obstruction (TRBO), no data are available for fully covered (FC) versus partially covered (PC) designs.

METHODS

PubMed, Scopus, and Cochrane databases were screened up to January 2023 for studies concerning dMBO treated by an FC- or PC-SEMS and describing adverse events (AEs), recurrences, or TRBO for specific design subpopulations. Pooled proportions or means were calculated using a random-effects model. Several subanalyses were preplanned, including a subanalysis restricted to prospective studies and unresectable diseases. Heterogeneity and publication bias were explored. Standardized differences (d-values) were calculated between groups.

RESULTS

From 1290 records, 62 studies (3327 using FC-SEMSs and 2322 using PC-SEMSs) were included. FC- versus PC-SEMSs showed negligible differences in the rate of total AEs (12% vs 9.9%) and all specific AEs, including cholecystitis (2.5% vs 2.6%). In a subanalysis restricted to prospective studies and unresectable diseases, the rate of RBO was comparable between FC-SEMSs (27.3% [95% confidence interval {CI}, 23.7-31.2], I2 = 35.34%) and PC-SEMSs (25.3% [95% CI, 20.2-30.7], I2 = 85.09%), despite small differences (d-values between .186 and .216) in the rate of ingrowth (.5% vs 2.9%) favoring FC-SEMSs and migration (9.8% vs 4.3%) favoring PC-SEMSs. TRBO was shorter for FC-SEMSs (238 days [95% CI, 191-286], I2 = 63.1%) versus PC-SEMSs (369 days [95% CI, 290-449], I2 = 71.9%; d-value = .116).

CONCLUSIONS

Despite considerable heterogeneity and small standardized differences, PC-SEMSs consistently exhibited longer TRBO than FC-SEMSs across analyses, without any other differences in AE rates, potentially proposing PC-SEMSs as the standard comparator and TRBO as the primary outcome for future randomized studies on dMBO. (Clinical trial registration number: CRD42023393965.).

Utility of Covered Self-Expanding Metal Stents for Biliary Drainage during Neoadjuvant Chemotherapy in Patients with Borderline Resectable Pancreatic Cancer

OBJECTIVES

We aimed to compare the utility of covered self-expanding metal stents (CSEMSs) with that of plastic stents (PSs) for biliary drainage during neoadjuvant chemotherapy in patients with borderline resectable pancreatic cancer.

METHODS

Forty patients with borderline resectable pancreatic cancer underwent biliary stenting during neoadjuvant chemotherapy at Hiroshima University Hospital. PSs and CSEMSs were placed in 19 and 21 patients, respectively. Two gemcitabine-based regimens for chemotherapy were used. Treatment outcomes and postoperative complications were compared between both groups.

RESULTS

The incidence of recurrent biliary obstruction was significantly lower in the CSEMS group (0% vs. 47.4%, p < 0.001), and the median time to recurrent biliary obstruction in the PS group was 47 days. There was no difference in the incidence of other complications such as non-occlusive cholangitis, pancreatitis, and cholecystitis between the two groups. Delays in the chemotherapy schedule due to stent-related complications were significantly frequent in the PS group (52.6% vs. 4.8%, p = 0.001). There was no significant difference in the incidence of postoperative complications between the two groups.

CONCLUSIONS

CSEMSs may be the best choice for safely performing neoadjuvant chemotherapy for several months in patients with borderline resectable pancreatic cancer with bile duct stricture.

Novel anti-reflux biliary metal stent with a distal tapered end for distal malignant biliary obstruction: a feasibility study

Background and study aims  We developed a self-expandable metallic stent (SEMS) with a distal tapered end to reproduce the physiological bile flow with a pressure gradient due to the difference in the diameter. We aimed to evaluate the safety and efficacy of the newly developed distal tapered covered metal stent (TMS) for distal malignant biliary obstruction (DMBO). Patients and methods  This single-center, prospective, single-arm study was conducted in patients with DMBO. The primary endpoint was time to recurrent biliary obstruction (TRBO), and the secondary endpoints were the survival time and incidence of adverse events (AEs). Results  Thirty-five patients (15 men, 20 women; median age, 81 years [range: 53-92]) were enrolled between December 2017 and December 2019. The primary diseases were pancreatic head cancer in 25 cases, bile duct cancer in eight cases, and ampullary cancer in two cases. TMS was successfully placed in all cases. Acute cholecystitis occurred as an early AE (within 30 days) in two cases (5.7 %). The median TRBO was 503 days, median survival time was 239 days. RBO was observed in 10 cases (28.6 %), and the causes were distal migration in six cases, proximal migration in two cases, biliary sludge in one case, and tumor overgrowth in one case. Conclusions  Endoscopic placement of the newly developed TMS in patients with DMBO is technically feasible and safe, and the TRBO was remarkably long. The anti-reflux mechanism based on the difference in diameter may be effective, and a randomized controlled trial with a conventional SEMS is required.

A case of delayed pancreatic fistula after covered self-expandable metallic stent deployment for pancreatic head cancer

A 69-year-old man was referred to our hospital with obstructive jaundice. A tumor with poor contrast enhancement was found in the pancreatic head, but there was no evidence of pancreatic atrophy, irregular stenosis, or dilation of the main pancreatic duct. He was diagnosed with borderline resectable pancreatic cancer with distal malignant biliary obstruction. After plastic stent placement, serum bilirubin levels improved, and chemotherapy was started. However, he developed cholangitis; thus, the plastic stent was replaced with a covered self-expandable metallic stent. He subsequently developed a delayed pancreatic fistula due to main pancreatic duct disruption. An endoscopic nasopancreatic duct drainage tube was placed to bridge the main pancreatic duct disruption after removing the covered self-expandable metallic stent. In addition, endoscopic ultrasound-guided transmural drainage was performed for the infected fluid collection caused by the pancreatic fistula, and the clinical symptoms quickly improved. This case presents the possibility of a delayed pancreatic fistula due to self-expandable metallic stent deployment. The need for considering such delayed complications when placing self-expanding metallic stents is highlighted.

Does endoscopic sphincterotomy contribute to the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis after endoscopic biliary stenting for malignant biliary obstruction? A multicenter prospective cohort study

BACKGROUND

There is no consensus on the necessity of endoscopic sphincterotomy (ES) to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) after endoscopic stenting in patients with malignant biliary obstruction. We investigated the incidence of PEP after endoscopic biliary stenting for malignant biliary obstruction with or without ES in a multicenter prospective cohort study.

METHODS

We enrolled 807 patients who underwent endoscopic biliary stenting for malignant biliary obstruction with a native papilla at 36 hospitals between April 2017 and March 2018. The incidence of PEP in patients with or without ES was compared for subgroups based on stent type, placement method, and patient background. Univariate and multivariate analysis was performed to investigate the incidence of PEP in all stenting patients.

RESULTS

Plastic and metal stents (MS) were inserted in 598 and 209 patients, respectively. The incidence of PEP in patients with or without ES was 7.9% and 7.4%, respectively among all stenting patients. The incidences of PEP with or without ES in plastic stent insertion patients, patients with MS insertion, stent insertions across the papilla, stent insertions across the papilla in patients without main pancreatic duct obstruction, and fully covered MS insertions across the papilla were compared. There was no overall significant difference in the incidence of PEP between those with or without ES. Multivariate logistic regression analysis for the incidence of PEP in all stenting patients revealed obstruction of the main pancreatic duct at the pancreatic head and epinephrine spraying on the papilla were significant factors; there was no significant difference in the incidence of PEP between patients with or without ES.

CONCLUSION

Endoscopic sphincterotomy may not contribute to the prevention of PEP after endoscopic biliary stenting for malignant biliary obstruction, even in cases of insertion with a fully covered MS across the papilla.

Risk of Pancreatitis Following Biliary Stenting With/Without Endoscopic Sphincterotomy: A Randomized Controlled Trial

BACKGROUND & AIMS

The efficacy of endoscopic sphincterotomy (ES) before endoscopic transpapillary biliary drainage in preventing post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) has not been established. The aim of this study was to evaluate the effect of performing ES before biliary stent/tube placement on the occurrence of PEP.

METHODS

Three hundred seventy patients with biliary stricture requiring endoscopic biliary stenting were enrolled and randomly allocated to the ES group (n = 185) or non-ES group (n = 185). All participants were followed up for 30 days after the procedure. The data and occurrence of adverse events were prospectively collected. The primary outcome measure of this study was the incidence of PEP within 2 days of initial transpapillary biliary drainage. Secondary outcome measures were the incidence of other adverse events related to biliary stent/tube placement.

RESULTS

PEP occurred in 36 patients (20.6%) in the non-ES group and in 7 patients (3.9%) in the ES group (P < .001). The difference in the incidence of PEP between the 2 groups in the per-protocol population was 16.7% (95% confidence interval, 10.1%-23.3%), which was not within the noninferiority margin of 6%. Except for bleeding, the incidences of other adverse events were not significantly different between the groups.

CONCLUSION

ES before endoscopic biliary stenting could have the preventive effect on the occurrence of PEP in patients with biliary stricture. University Hospital Medical Information Network Number, UMIN000025727.University Hospital Medical Information Network Clinical Trial Registry URL: https://www.umin.ac.jp/ctr/index.htm.

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.

Efficacy of endoscopic samplings during initial biliary drainage for cases of pancreatic head cancer: United diagnostic yields of multiple pathological samplings

BACKGROUND/OBJECTIVES

The diagnostic ability of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been fully studied; however, the efficacy of other endoscopic samplings (OESs) is less clear. The aim of this study was to examine the diagnostic efficacies of OESs for pancreatic head cancer (PHC).

METHODS

The diagnostic efficacies of endoscopic samplings were retrospectively analyzed in 448 PHC cases and 63 cases of mass-forming pancreatitis (MFP) during initial transpapillary biliary drainage. The OESs included duodenal biopsy (118 PHCs and 50 MFPs), biliary biopsy (218 and 51) with cytology (368 and 53), and pancreatic duct biopsy (23 and 13) with cytology (56 and 43). EUS-FNA was conducted in a different session (149 and 62). Factors associated with OES sensitivity were analyzed. The sensitivity of biliary biopsy was compared between 1.95 mm and 1.8 mm forceps.

RESULTS

Cancer cells were confirmed in 87.9% of the EUS-FNA samplings and in 64.1% (268/418) obtained by combined OESs (average 1.7 OES types per case): 68.6% by duodenal biopsy, 59.6% by biliary biopsy, 32.6% by biliary cytology, 73.9% by pancreatic duct biopsy, and 33.9% by pancreatic duct cytology. No MFP cases revealed cancer by any sampling. OESs did not increase adverse events. Duodenal stenosis, serum bilirubin, tumor size, and pancreatic juice amounts were associated with OES sensitivity. Biliary biopsy had the same sensitivity with different forceps.

CONCLUSION

EUS-FNA was the most diagnostic protocol; however, OESs can be safely applied during the initial biliary drainage to reduce the demand for EUS-FNA while providing good diagnostic yields.

Current Status of Endoscopic Biliary Drainage in Patients with Distal Malignant Biliary Obstruction

Distal malignant biliary obstruction is caused by various malignant diseases that require biliary drainage. In patients with operable situations, preoperative biliary drainage is required to control jaundice and cholangitis until surgery. In view of tract seeding, endoscopic biliary drainage is the first choice. Since neoadjuvant therapies are being developed, the time to surgery is increasing, especially in pancreatic cancer cases. Therefore, it requires long stent patency. Recently, preoperative biliary drainage using self-expandable metal stents has been reported as a useful modality to secure long stent patency. In patients with unresectable distal malignant biliary obstruction, self-expandable metal stent is the first choice for maintaining long stent patency. Although there are many comparison studies between a covered and an uncovered self-expandable metal stent, their use is still controversial. Recently, endoscopic ultrasound-guided biliary drainage has been performed as an alternative treatment. The clinical success and stent patency are favorable. We should take into consideration that both endoscopic retrograde cholangiopancreatography-guided biliary drainage and endoscopic ultrasound-guided biliary drainage have advantages and disadvantages and chose the drainage method depending on the patient’s situation or the expertise of the endoscopist. Here, we discuss the current status of endoscopic biliary drainage in patients with distal malignant biliary obstruction.

Development of Severe Acute Pancreatitis Following Uncovered Metallic Stent Placement: A Rare Case Report

Self-expandable metallic stents (SEMSs) are widely used for malignant biliary stricture (MBS). Acute pancreatitis is an early complication following SEMS placement. In the present case, the patient developed severe acute pancreatitis after SEMS placement for MBS because of metastatic lymph nodes. Endoscopic retrograde cholangiopancreatography, endoscopic sphincterotomy and an endoscopic nasobiliary drainage tube placement were performed. After seven days, an uncovered SEMS was placed; however, severe acute pancreatitis occurred, and the SEMS was drawn out emergently. In SEMS placement for patients with MBS caused by non-pancreatic cancer, SEMS should be selected carefully while considering each patient's case.

A Prospective Multicenter Study of Partially Covered Metal Stents in Patients Receiving Neoadjuvant Chemotherapy for Resectable and Borderline Resectable Pancreatic Cancer: BTS-NAC Study

Background/Aims

The aim of this study was to evaluate the safety and efficacy of partially covered self-expandable metallic stents (PCSEMS) in patients undergoing neoadjuvant chemo(radio) therapy (NAC) for pancreatic cancer (PC).

Methods

This was a prospective multicenter study to evaluate the safety and efficacy of PCSEMS in patients receiving NAC for resectable and borderline resectable PC. The primary endpoint was the rate of recurrent biliary obstruction (RBO).

Results

Twenty-six patients with PC (three with resectable PC and 23 with borderline resectable PC) who underwent NAC at seven Japanese centers were included in the analysis. Both the technical and functional success rates of PCSEMS placement were 100%. Early stent-related complications were observed in three patients (11.5%): mild pancreatitis (n=2) and mild liver abscess (n=1). The median time to surgery or palliation was 4.0 months. Surgical resection was eventually performed in 73.1% of patients, and stent removal during surgery was successful in all patients. RBO was observed in nine patients (34.6%): seven with stent occlusion, one with kinking and one with migration. The RBO rates in resected cases and nonresected cases were 36.8% and 28.6%, respectively.

Conclusions

Biliary drainage by PCSEMS was safe and feasible in patients undergoing NAC for resectable and borderline resectable PC.

Intraductal placement of a fully covered metal stent with a long string for distal malignant biliary obstruction without endoscopic sphincterotomy: Prospective multi-center feasibility study

BACKGROUND

Stent migration and sludge clogging are characteristic problems in biliary covered self-expandable metal stent (SEMS) placement. Intraductal placement without endoscopic sphincterotomy (ES) may help reduce their occurrence. We examined the feasibility of intraductal placement of a covered SEMS with a long string without ES in patients with unresectable distal malignant biliary obstruction (MBO).

METHODS

This was a prospective multi-center observational study. Forty patients with distal MBO were enrolled between July 2016 and August 2018. We evaluated recurrent biliary obstruction (RBO), adverse events other than RBO, and reintervention associated with intraductal placement without ES.

RESULTS

Both technical and functional success rates were 100% (40/40). The rate of adverse events other than RBO was 5% (2/40). The RBO rate was 33% (13/40), and the median time to RBO was 339 days. RBO was mainly caused by overgrowth on the papillary side, occurring in six patients; all such patients had pancreatic cancer and a distance between the papilla and the stricture of ≤20 mm. Other causes were overgrowth at the hepatic side in two patients and sludge in five patients. No instances of stent migration occurred. Success rates of endoscopic transpapillary reintervention and stent removal using the string were 92% (12/13) and 77% (10/13), respectively.

CONCLUSIONS

Intraductal placement without ES using a long-stringed covered SEMS is a promising option for distal MBO. Since overgrowth on the papillary side is frequent, the procedure should be avoided in patients with short distances between the stricture and the papilla. (Clinical Trial Registry: UMIN000023370).

Self-expandable metallic stent placement above the papilla without endoscopic sphincterotomy in patients with distal malignant biliary obstruction

Background and study aims  The best method for endoscopic placement of self-expandable metallic stents (SEMS) for distal malignant biliary obstruction (MBO) has not yet been determined. The aim of this study was to evaluate how SEMS placement above the papilla and without endoscopic sphincterotomy (EST) impacts the time to recurrent biliary obstruction (RBO) in patients with distal MBO. Patients and methods  We retrospectively reviewed data for 73 consecutive patients with unresectable distal MBO who underwent endoscopic SEMS placement for the first time at our institution between April 2014 and March 2016. We compared time to RBO of SEMS placement above the papilla (intraductal placement) with SEMS placement across the papilla (transpapillary placement). In the intraductal placement group, we also compared time to RBO of placement without EST with placement with EST. Results  Endoscopic SEMS placement was performed in 30 patients with intraductal placement and in 43 patients with transpapillary placement. The median time to RBO was significantly longer with intraductal placement (307 days) than with transpapillary placement (161 days) ( P  = 0.022). Complication rates did not differ between the two groups. In both univariate and multivariate analysis, intraductal placement was an independent factor contributing to prolonged time to RBO. In intraductal placement, time to RBO was significantly longer in SEMS placement without EST than with EST (363 days vs. 227 days, respectively; P  = 0.026). Conclusions  Intraductal SEMS placement, especially without EST for distal MBO contributed to longer time to RBO.

Inutility of endoscopic sphincterotomy to prevent pancreatitis after biliary metal stent placement in the patients without pancreatic duct obstruction

Background: The incidence of post-ERCP pancreatitis (PEP) has been reported to be significantly higher in patients without main pancreatic duct (MPD) obstruction who undergo transpapillary biliary metal stent (MS) placement than in those with ordinary ERCP setting.Objective: To evaluate the benefit of endoscopic sphincterotomy (ES) prior to MS placement in preventing PEP in patients with distal malignant biliary obstruction (MBO) without MPD obstruction.Materials and methods: In total, 160 patients who underwent initial MS placement for MBO were enrolled. Eighty-two patients underwent ES immediately prior to MS placement, whereas 78 underwent MS placement without ES. An inverse probability of treatment weighting method was adopted to adjust the differences of the patients' characteristics. The primary outcome was the incidence of PEP. The secondary outcomes included the incidence of other adverse events (bleeding, cholangitis, perforation and stent dislocation) and time to recurrent biliary obstruction.Results: The incidence of PEP was 26.8% in the ES and 23.1% in the non-ES (unadjusted odds ratio [OR] [95%CI]: 1.22, [0.60-2.51], adjusted OR [95%CI]: 1.23, [0.53-2.81], p = .63). Logistic-regression analysis revealed no factors that could be attributed to the occurrence of PEP. The incidence of other adverse events was not different between the groups. The median time to recurrent biliary obstruction was 131 (2-465) days and 200 (4-864) days in the ES and non-ES, respectively (p = .215).Conclusions: ES prior to MS placement for patients with distal MBO without MPD obstruction does not reduce the incidence of PEP.

Antireflux covered metal stent for nonresectable distal malignant biliary obstruction: Multicenter randomized controlled trial

BACKGROUND AND AIM

An antireflux metal stent (ARMS) for nonresectable distal malignant biliary obstruction (MBO) may prevent recurrent biliary obstruction (RBO) as a result of duodenobiliary reflux and prolong time to RBO (TRBO). Superiority of ARMS over conventional covered self-expandable metal stents (SEMS) has not been fully examined.

METHODS

We conducted a multicenter randomized controlled trial to examine whether TRBO of an ARMS with a funnel-shaped valve was longer than that of a covered SEMS in SEMS-naïve patients. We enrolled 104 patients (52 patients per arm) at 11 hospitals in Japan. Secondary outcomes included causes of RBO, adverse events, and patient survival.

RESULTS

TRBO did not differ significantly between the ARMS and covered SEMS groups (median, 251 vs 351 days, respectively; P = 0.11). RBO as a result of biliary sludge or food impaction was observed in 13% and 9.8% of patients who received an ARMS and covered SEMS, respectively (P = 0.83). ARMS was associated with a higher rate of stent migration compared with the covered SEMS (31% vs 12%, P = 0.038). Overall rates of adverse events were 20% and 18% in the ARMS and covered SEMS groups, respectively (P = 0.97). No significant between-group difference in patient survival was observed (P = 0.26).

CONCLUSIONS

The current ARMS was not associated with longer TRBO compared with the covered SEMS. Modifications including addition of an anti-migration system are required to use the current ARMS as first-line palliative treatment of distal MBO (UMIN-CTR clinical trial registration number: UMIN000014784).

Stenting for Benign and Malignant Biliary Strictures

Benign and malignant biliary strictures are common indications for endoscopic retrograde cholangiopancreatography. Diagnosis involves high-quality cross-sectional imaging and cholangiography with various endoscopic sampling techniques. Treatment options include placement of plastic biliary stents and self-expanding metal stents, which differ in patency duration and cost effectiveness. Whether the etiology is benign or malignant, a multidisciplinary strategy should be implemented. This article will discuss general principles of biliary stenting in both benign and malignant conditions.

Endoscopic Sphincterotomy before Fully Covered Metal Stent Placement Is Not Required for Distal Malignant Biliary Stricture due to a Pancreatic Head Tumor

Background/Aims

Endoscopic sphincterotomy (EST) is often performed before fully covered self-expandable metal stent (FCSEMS) placement in order to prevent pancreatitis. However, it is not clear whether EST prevents pancreatitis or affects other adverse events (AEs). This study is conducted to evaluate the necessity of EST before FCSEMS placement for distal malignant biliary strictures due to a pancreatic head tumor.

Methods

This study included 68 patients who underwent FCSEMS placement for distal malignant biliary stricture due to a pancreatic head tumor. Treatment outcomes and AEs were retrospectively compared between 32 patients with EST before FCSEMS placement (EST group) and 36 patients without EST (non-EST group).

Results

The success rates of drainage for the EST and non-EST groups were 100% and 97.2%, respectively (P = 0.95). The incidence of pancreatitis in the EST and non-EST groups was 3.1% and 0%, respectively (P = 0.95). The incidence of hyperamylasemia in the EST and non-EST groups was 12.5% and 13.9%, respectively (P = 0.85). The incidence of all AEs in the EST and non-EST groups was 15.6% (pancreatitis: 1, cholecystitis: 2, and stent migration: 2) and 13.9% (cholecystitis: 3, stent migration: 2), respectively (P = 0.89).

Conclusions

EST before FCSEMS placement for distal malignant biliary stricture due to a pancreatic head tumor does not affect the successful drainage and incidence of adverse events. The necessity of EST to prevent pancreatitis before FCSEMS placement was deemed low.

Endoscopic biliary self-expandable metallic stent in malignant biliary obstruction with or without sphincterotomy: systematic review and meta-analysis

Background and aim  To assess the rate of adverse events and the technical success rate of biliary stenting with or without EBS.  Methods  A literature search up to February 2017 was performed. Studies assessing adverse events (AEs) and technical success rates of stenting with or without EBS were considered. Results  Seven studies (870 patients; 12 treatment arms) were included. Early AEs, i. e. those occurring within 30 days, were significantly lower in no-EBS vs. EBS-group (11 % vs . 20.1 %; OR: 0.36, 95 %CI: 0.13 - 1.00). Rates of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis were not significantly different in the two groups (no-EBS vs . EBS: 6.1 % vs 5 %; OR: 1.33, 95 %CI: 0.68 - 2.59). The rate of bleeding was significantly lower in patients without EBS (no-EBS vs EBS: 0 % vs 5 %; OR: 0.12, 95 % CI: 0.03 - 0.45). Rates of cholangitis were significantly lower in patients without EBS (no-EBS vs . EBS: 3.3 % vs. 7.4 %; OR: 0.38, 95 %CI: 0.17 - 0.83). Both late AEs and mortality rates did not significantly differ between no-EBS and EBS patients (19.9 % vs. 18.9 %; OR: 0.93, 95 %CI: 0.56 - 1.53, and 2.5 % vs. 2.9 %; OR: 1.18, 95 %CI: 0.22 - 6.29, respectively). The technical success rate for stent insertion also did not differ (98 % vs. 97.6 %; OR: 1.05, 95 %CI: 0.42 - 2.63). Conclusion  EBS seems to be associated, in the first 30 days after the procedure, with an increased risk of cholangitis and bleeding. No difference was observed in the rate of post-ERCP pancreatitis.

Prospective multicenter study of primary EUS-guided choledochoduodenostomy using a covered metal stent

Background and Objectives:

EUS-guided biliary drainage (EUS-BD) is increasingly reported as a salvage technique after failed endoscopic retrograde cholangiopancreatography, but it is still controversial whether EUS-BD can replace transpapillary biliary stenting. Therefore, we conducted this multicenter, prospective study of EUS-guided choledochoduodenostomy (EUS-CDS) using a covered metallic stent (CMS) as primary biliary drainage for unresectable distal malignant biliary obstruction (MBO).

Methods:

Patients with unresectable distal MBO without any prior drainage are enrolled. Primary endpoint is a technical success and secondary endpoints are adverse events, functional success, and recurrent biliary obstruction (RBO) of EUS-CDS. Clinical outcomes were compared between EUS-CDS and transpapillary stenting as a control.

Results:

A total of 34 patients were enrolled in 10 Japanese institutions. The cause of MBO was pancreatic cancer in 28 patients. Median tumor size and common bile duct diameter were 31 and 13 mm, respectively. Technical success rate was 97% with a median procedure time of 25 min and functional success rate was 100%. The rate of RBO was 29% and the causes of RBO were nontumor related: Migration in 18%, sludge/food impaction in 9%, and stent impaction to the duodenal wall in 3%. Other adverse events were abdominal pain in 6% and cholecystitis in 9%. A median cumulative time to RBO was 11.3 months. The rate of RBO and cumulative time to RBO of EUS-CDS were comparable to those of transpapillary stenting (36% and 9.1 months, respectively).

Conclusion:

EUS-CDS using a CMS as primary biliary drainage was technically feasible and its safety appeared comparable to transpapillary stenting.

Risk Factors for Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis: Evidence from 1786 Cases

BACKGROUND Postoperative pancreatitis is one of the most serious complications in endoscopic retrograde cholangiopancreatography (ERCP). To detect potential risk factors for post-ERCP hyperamylasemia and pancreatitis. MATERIAL AND METHODS We reviewed 1786 ERCP procedures in Zhongnan Hospital of Wuhan University from January 2015 to April 2018. Clinical data were extracted, and the complications after ERCP procedures were re-evaluated. Single- and multiple-variable analyses were conducted to detect the potential risk factors. RESULTS We found that 1786 procedures were applied on 1707 patients; 64 patients (3.58%) developed pancreatitis, while asymptomatic hyperamylasemia occurred in 263 cases (14.73%). In multivariate analysis, pancreatic deep wire pass (odds ratio [OR]: 2.280, 95% CI [confidence interval]: 1.129-4.605, P=0.022), endoscopic metal biliary endoprosthesis (OR: 2.399, 95% CI: 1.120-5.138, P=0.024), operation after liver transplantation (OR: 3.057, 95% CI: 1.110-8.422, P=0.031), and fistulotomy (OR: 3.148, 95% CI: 1.036-9.561, P=0.043) were identified as independent risk factors for post-ERCP pancreatitis. Pancreatic deep wire pass (OR: 1.678, 95% CI: 1.136-2.478, P=0.009), fistulotomy (OR: 2.553, 95% CI: 1.096-5.948, P=0.030), and younger age (OR: 0.990, 95% CI: 0.980-0.999, P=0.037) were identified as independent risk factors for hyperamylasemia. CONCLUSIONS To prevent post-ERCP pancreatitis, it is important to avoid high-risk procedures such as fistulotomy and pancreatic deep wire pass, especially in high-risk patients with liver transplantation. For patients with endoscopic metal biliary endoprosthesis, clinicians should pay more attention to the occurrence of post-ERCP pancreatitis.

A Prospective Multicenter Study of a Fully Covered Metal Stent in Patients with Distal Malignant Biliary Obstruction: WATCH-2 Study

BACKGROUND

Both fully covered (FC) and partially covered (PC) self-expandable metal stents (SEMSs) are now commercially available for distal malignant biliary obstruction (MBO). While FCSEMS can be easily removed at the time of re-interventions, it is theoretically prone to migration. However, few comparative data between FC and PC SEMSs have been reported.

AIMS

The aim of this study was to compare clinical outcomes of FCSEMS with those of PCSEMS.

METHODS

This was a multicenter, prospective study of FCSEMS for unresectable distal MBO with a historical control of PCSEMS, which was previously reported as the WATCH study. The primary outcome was recurrent biliary obstruction (RBO), and secondary outcomes were stent migration, stent removal, stent-related adverse events, and survival.

RESULTS

A total of 151 cases with unresectable distal MBO undergoing FCSEMS placement were enrolled and compared with a historical cohort of 141 cases undergoing PCSEMS placement. No significant differences were found in the rate of RBO (29 vs. 33%; P = 0.451), time to RBO (318 vs. 373 days; P = 0.382), and survival (229 vs. 196 days; P = 0.177) between FCSEMS and PCSEMS. The rate of stent migration also did not differ significantly between the two groups (14 vs. 8%; P = 0.113). The removal of FCSEMSs was successful in all 24 attempted cases (100%).

CONCLUSIONS

FCSEMSs appeared comparable to PCSEMSs in terms of RBO without a significant increase in stent migration rate in patients with unresectable distal MBO.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000007131.

Multicenter study of endoscopic preoperative biliary drainage for malignant hilar biliary obstruction: E-POD hilar study

BACKGROUND AND AIM

Endoscopic nasobiliary drainage (ENBD) is often recommended in preoperative biliary drainage (PBD) for hilar malignant biliary obstruction (MBO), but endoscopic biliary stent (EBS) is also used in the clinical practice. We conducted this large-scale multicenter study to compare ENBD and EBS in this setting.

METHODS

A total of 374 cases undergoing PBD including 281 ENBD and 76 EBS for hilar MBO in 29 centers were retrospectively studied.

RESULTS

Extrahepatic cholangiocarcinoma (ECC) accounted for 69.8% and Bismuth-Corlette classification was III or more in 58.8% of the study population. Endoscopic PBD was technically successful in 94.6%, and adverse event rate was 21.9%. The rate of post-endoscopic retrograde cholangiopancreatography pancreatitis was 16.0%, and non-endoscopic sphincterotomy was the only risk factor (odds ratio [OR] 2.51). Preoperative re-intervention was performed in 61.5%: planned re-interventions in 48.4% and unplanned re-interventions in 31.0%. Percutaneous transhepatic biliary drainage was placed in 6.4% at the time of surgery. The risk factors for unplanned procedures were ECC (OR 2.64) and total bilirubin ≥ 10 mg/dL (OR 2.18). In surgically resected cases, prognostic factors were ECC (hazard ratio [HR] 0.57), predraiange magnetic resonance cholangiopancreatography (HR 1.62) and unplanned re-interventions (HR 1.81). EBS was not associated with increased adverse events, unplanned re-interventions, or a poor prognosis.

CONCLUSIONS

Our retrospective analysis did not demonstrate the advantage of ENBD over EBS as the initial PBD for resectable hilar MBO. Although the technical success rate of endoscopic PBD was high, its re-intervention rate was not negligible, and unplanned re-intervention was associated with a poor prognosis in resected hilar MBO.

International study of endoscopic management of distal malignant biliary obstruction combined with duodenal obstruction

OBJECTIVE

Endoscopic transpapillary or endoscopic ultrasound (EUS)-guided stent placement is used for nonresectable distal malignant biliary obstruction. We conducted a retrospective study to evaluate endoscopic biliary drainage in patients with duodenal obstruction.

METHODS

We included consecutive patients who underwent endoscopic biliary drainage combined with a duodenal stent at 16 referral centers in four Asian countries. The primary outcome was time to recurrent biliary obstruction (TRBO). We assessed TRBO according to the sequence of biliary and duodenal obstruction (group 1/2/3, biliary obstruction first/concurrent/duodenal obstruction first, respectively) or the location of duodenal obstruction (type I/II/III, proximal to/affecting/distal to the ampulla, respectively). We also evaluated functional success and adverse events.

RESULTS

We included 110 patients (group1/2/3, 67/29/14 patients; type I/II/III, 45/46/19 patients; endoscopic retrograde cholangiopancreatography [ERCP]/EUS-guided choledocoduodenostomy/EUS-guided hepaticogastrostomy, 90/10/10 patients, respectively). The median TRBO of all cases was 450 days (interquartile range, 212-666 days) and functional success was achieved in 105 cases (95%). The TRBO did not differ significantly by the timing or location of duodenal obstruction (p = .30 and .79, respectively). The TRBO of metal stents (n = 96) tended to be longer compared with plastic stents (n = 14, p = .083). Compared with ERCP, EUS-guided biliary drainage was associated with a higher rate of adverse events.

CONCLUSION

Transpapillary or transmural endoscopic biliary drainage with a duodenal stent was effective, irrespective of the timing or location of duodenal obstruction. A prospective study is required considering the tradeoff of technical success rate, stent patency, and adverse events (ClinicalTrials.gov number, NCT02376907).

Effect of endoscopic transpapillary biliary drainage with/without endoscopic sphincterotomy on post-endoscopic retrograde cholangiopancreatography pancreatitis in patients with biliary stricture (E-BEST): a protocol for a multicentre randomised controlled trial

INTRODUCTION

The effect of endoscopic sphincterotomy prior to endoscopic biliary stenting to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis remains to be fully elucidated. The aim of this study is to prospectively evaluate the non-inferiority of non-endoscopic sphincterotomy prior to stenting for naïve major duodenal papilla compared with endoscopic sphincterotomy prior to stenting in patients with biliary stricture.

METHODS AND ANALYSIS

We designed a multicentre randomised controlled trial, for which we will recruit 370 patients with biliary stricture requiring endoscopic biliary stenting from 26 high-volume institutions in Japan. Patients will be randomly allocated to the endoscopic sphincterotomy group or the non-endoscopic sphincterotomy group. The main outcome measure is the incidence of pancreatitis within 2 days of initial transpapillary biliary drainage. Data will be analysed on completion of the study. We will calculate the 95% confidence intervals (CIs) of the incidence of pancreatitis in each group and analyse weather the difference in both groups with 95% CIs is within the non-inferiority margin (6%) using the Wald method.

ETHICS AND DISSEMINATION

This study has been approved by the institutional review board of Hokkaido University Hospital (IRB: 016-0181). Results will be submitted for presentation at an international medical conference and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

The University Hospital Medical Information Network ID: UMIN000025727 Pre-results.

Survey study on the practice patterns in the endoscopic management of malignant distal biliary obstruction

BACKGROUND AND STUDY AIM

 Endoscopic biliary drainage for malignant distal biliary obstruction (MDBO) is a common practice. Controversy persists with regard to its role in resectable MDBO, the optimal technical method and type of stent. The aim of this study was to evaluate practice patterns in the treatment of MDBO among endoscopists with varying levels of experience and practice backgrounds.

METHODS

 Electronic survey distributed to members of the American Society for Gastrointestinal Endoscopy (ASGE). The main outcome measures included practice setting (academic vs. community), volume of endoscopic retrograde cholangiopancreatographies (ERCPs), reasons for endoscopic drainage in MDBO, and technical approach.

RESULTS

 A total of 335 subjects (54 % community-based endoscopists) completed the survey. Most academic physicians (69 %) reported performing ≥ 150 ERCPs annually compared to 18.8 % of community physicians ( P  < 0.001). In aggregate, 13.1 % of respondents performed ERCP in resectable MDBO because of surgeon preference or as the standard of care at their institution. The use of metal vs. plastic stents in MDBO varied based on practice setting. Routine sphincterotomy for MDBO was more common among community (78 %) vs academic endoscopists (61.1 %) ( P  < 0.001). Over half (58 %) of the subjects avoided covering the cystic duct take-off during stenting MDBO if there was a gallbladder in situ.

CONCLUSION

 There is significant variability in practice patterns for the treatment of MDBO. In spite of the recent ASGE guideline recommendations, some patients with resectable MDBO still undergo preoperative ERCP. Current clinical practices are not clearly supported by available data and underscore the need to increase adherence to gastrointestinal societal recommendations and an evidence-based approach to standardized patient care.

Efficacy and safety of limited endoscopic sphincterotomy before self-expandable metal stent insertion for malignant biliary obstruction

AIM

To evaluate the safety and efficacy of limited endoscopic sphincterotomy (ES) before placement of self-expandable metal stent (SEMS).

METHODS

This was a retrospective analysis of 244 consecutive patients with unresectable malignant biliary obstruction, who underwent placement of SEMSs following limited ES from December 2008 to February 2015. The diagnosis of malignant biliary obstruction and assessment of patient eligibility for the study was established by a combination of clinical findings, laboratory investigations, imaging and pathological results. All patients were monitored in the hospital for at least 24 h following endoscopic retrograde cholangio pancreatography (ERCP). The incidence of immediate or early post-ERCP complications such as post-ERCP pancreatitis (PEP) and bleeding related to limited ES were considered as primary outcomes. Also, characteristics and complications according to the cancer type were classified.

RESULTS

Among the 244 patients included, the underlying diagnosis was cholangiocarcinoma in 118 patients, pancreatic cancer in 79, and non-pancreatic or non-biliary malignancies in the remaining 47 patients. Early post-ERCP complications occurred in 9 patients (3.7%), with PEP in 7 patients (2.9%; mild, 6; moderate, 1) and mild bleeding in 2 patients (0.8%). There was no significant association between the incidence of post-ERCP complications and the type of malignancy (cholangiocarcinoma vs pancreatic cancer vs others, P = 0.696) or the type of SEMS used (uncovered vs covered, P = 1.000). Patients who had more than one SEMS placed at the first instance were at a significantly higher risk of post-ERCP complications (one SEMS vs two SEMS, P = 0.031). No other factors were predictive of post-ERCP complications.

CONCLUSION

Limited ES is feasible and safe, and effectively facilitates the placement of SEMS, without any significant risk of PEP or severe bleeding.

Understanding the Mechanical forces of Self-Expandable Metal Stents in the Biliary Ducts

Self-expandable metallic stent (SEMS) was an effective biliary endoprosthesis. Mechanical properties of SEMS, radial and axial force (RF, AF), may play important roles in the bile duct after placement. RF was well known dilation force and influenced on the occurrence of migration. AF, newly proposed by this author, was defined as the recovery force when the SEMS vended. AF was related with the cause of bile duct kinking, pancreatitis, and cholecystitis due to the compression of the bile duct, orifice of the cystic duct, and pancreatic orifice. Ideal SEMS may show high RF and low AF.

Cost-effectiveness and clinical efficacy of biliary stents in patients undergoing neoadjuvant therapy for pancreatic adenocarcinoma in a randomized controlled trial

BACKGROUND AND AIMS

The optimal type of stent for the palliation of malignant biliary obstruction in patients with pancreatic adenocarcinoma undergoing neoadjuvant chemoradiotherapy with curative intent is unknown. We performed a prospective trial comparing 3 types of biliary stents-fully covered self-expandable metal (fcSEMS), uncovered self-expandable metal (uSEMS), and plastic-to determine which best optimized cost-effectiveness and important clinical outcomes.

METHODS

In this prospective randomized trial, consecutive patients with malignant biliary obstruction from newly diagnosed pancreatic adenocarcinoma who were to start neoadjuvant chemoradiotherapy were randomized to receive fcSEMSs, uSEMSs, or plastic stents during the index ERCP. The primary outcomes were time to stent occlusion, attempted surgical resection, or death after the initiation of neoadjuvant therapy, and the secondary outcomes were total patient costs associated with the stent, including the index ERCP cost, downstream hospitalization cost due to stent occlusion, and the cost associated with procedural adverse event.

RESULTS

Fifty-four patients were randomized and reached the primary end point: 16 in the fcSEMS group, 17 in the uSEMS group, and 21 in the plastic stent group. No baseline demographic or tumor characteristic differences were noted among the groups. The fcSEMSs had a longer time to stent occlusion compared with uSEMSs and plastic stents (220 vs 74 and 76 days, P < .01), although the groups had equivalent rates of stent occlusion, attempted surgical resection, and death. Although SEMS placement cost more during the index ERCP (uSEMS = $24,874 and fcSEMS = $22,729 vs plastic = $18,701; P < .01), they resulted in higher procedural AE costs per patient (uSEMS = $5522 and fcSEMS = $12,701 vs plastic = $0; P < .01). Conversely, plastic stents resulted in an $11,458 hospitalization cost per patient due to stent occlusion compared with $2301 for uSEMSs and $0 for fcSEMSs (P < .01).

CONCLUSIONS

In a prospective trial comparing fcSEMSs, uSEMSs, and plastic stents for malignant biliary obstruction in patients undergoing neoadjuvant therapy with curative intent for pancreatic adenocarcinoma, no stent type was superior in optimizing cost-effectiveness, although fcSEMSs resulted in fewer days of neoadjuvant treatment delay and a longer time to stent occlusion. (Clincial trial registration number: NCT01038713.).

Lower incidence of complications in endoscopic nasobiliary drainage for hilar cholangiocarcinoma

AIM: To identify the most effective endoscopic biliary drainage technique for patients with hilar cholangiocarcinoma.

METHODS: In total, 118 patients with hilar cholangiocarcinoma underwent endoscopic management [endoscopic nasobiliary drainage (ENBD) or endoscopic biliary stenting] as a temporary drainage in our institution between 2009 and 2014. We retrospectively evaluated all complications from initial endoscopic drainage to surgery or palliative treatment. The risk factors for biliary reintervention, post-endoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis, and percutaneous transhepatic biliary drainage (PTBD) were also analyzed using patient- and procedure-related characteristics. The risk factors for bilateral drainage were examined in a subgroup analysis of patients who underwent initial unilateral drainage.

RESULTS: In total, 137 complications were observed in 92 (78%) patients. Biliary reintervention was required in 83 (70%) patients. ENBD was significantly associated with a low risk of biliary reintervention [odds ratio (OR) = 0.26, 95%CI: 0.08-0.76, P = 0.012]. Post-ERCP pancreatitis was observed in 19 (16%) patients. An absence of endoscopic sphincterotomy was significantly associated with post-ERCP pancreatitis (OR = 3.46, 95%CI: 1.19-10.87, P = 0.023). PTBD was required in 16 (14%) patients, and Bismuth type III or IV cholangiocarcinoma was a significant risk factor (OR = 7.88, 95%CI: 1.33-155.0, P = 0.010). Of 102 patients with initial unilateral drainage, 49 (48%) required bilateral drainage. Endoscopic sphincterotomy (OR = 3.24, 95%CI: 1.27-8.78, P = 0.004) and Bismuth II, III, or IV cholangiocarcinoma (OR = 34.69, 95%CI: 4.88-736.7, P < 0.001) were significant risk factors for bilateral drainage.

CONCLUSION: The endoscopic management of hilar cholangiocarcinoma is challenging. ENBD should be selected as a temporary drainage method because of its low risk of complications.

Post-biliary sphincterotomy bleeding despite covered metallic stent deployment

Objectives:

Several endoscopic techniques have been proposed for the management of post-sphincterotomy bleeding. Lately, self-expandable metal stents deployment has gained popularity especially as a rescue therapy when other endoscopic techniques fail.

Methods-results:

We report the case report of a massive post-sphincterotomy bleeding in a patient with a self-expandable metal stent in the biliary tree. Despite the presence of a correctly positioned self-expandable metal stent, a new endoscopic session was required to control the bleeding.

Conclusions:

Self-expandable metal stent may be useful to manage post-endoscopic sphincterotomy bleeding. However, up to now there is no specifically designed self-expandable metal stent for such complication. Large new designed self-expandable metal stent may be a useful tool for biliary endoscopist.

Does endoscopic sphincterotomy reduce the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis after biliary stenting? A systematic review and meta-analysis

BACKGROUND AND AIM

Endoscopic biliary sphincterotomy (ES) is often carried out prior to placement of a biliary stent apparently to reduce the risk of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). However, the protective effect of ES prior to biliary stenting is controversial. The objective of this meta-analysis is to compare the risk of PEP and other complications after the placement of biliary stent with or without ES in patients with biliary obstruction and bile leak.

METHODS

We carried out a systematic search in several electronic databases for randomized controlled trials (RCT) and observational studies (OS) comparing the risk of PEP after biliary stenting with or without ES. The Mantel-Haenszel method was used to pool data of adverse outcomes into fixed or random effect model meta-analyses.

RESULTS

Seventeen studies (five RCT and 12 OS) with a total of 2710 patients met the inclusion criteria. No significant difference was observed in the risk of PEP with biliary stenting with and without ES (RD -0.01; 95% confidence interval [CI] -0.03, 0.01). In a subgroup analysis of stenting for biliary obstruction, no difference in the risk of PEP was observed with or without ES. However, ES was associated with lower risk of PEP in patients undergoing biliary stenting for bile leak (RD -0.05; CI -0.10, -0.01).

CONCLUSIONS

ES shows risk reduction in prevention of PEP in patients undergoing endoscopic stenting for bile leak. However, placement of biliary stent without ES is not associated with an increased risk of PEP in patients with distal bile duct obstruction with involvement of pancreatic duct.

Covered versus Uncovered Self-Expandable Metal Stents for Managing Malignant Distal Biliary Obstruction: A Meta-Analysis

AIM

To compare the efficacy of using covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (UCSEMSs) to treat objective jaundice caused by an unresectable malignant tumor.

METHODS

We performed a comprehensive electronic search from 1980 to May 2015. All randomized controlled trials comparing the use of CSEMSs and UCSEMSs to treat malignant distal biliary obstruction were included.

RESULTS

The analysis included 1417 patients enrolled in 14 trials. We did not detect significant differences between the UCSEMS group and the CSEMS group in terms of cumulative stent patency (hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.19-4.53; p = 0.93, I2 = 0%), patient survival (HR 0.77, 95% CI 0.05-10.87; p = 0.85, I2 = 0%), overall stent dysfunction (relative ratio (RR) 0.85, M-H, random, 95% CI 0.57-1.25; p = 0.83, I2 = 63%), the overall complication rate (RR 1.26, M-H, fixed, 95% CI 0.94-1.68; p = 0.12, I2 = 0%) or the change in serum bilirubin (weighted mean difference (WMD) -0.13, IV fixed, 95% CI 0.56-0.3; p = 0.55, I2 = 0%). However, we did detect a significant difference in the main causes of stent dysfunction between the two groups. In particular, the CSEMS group exhibited a lower rate of tumor ingrowth (RR 0.25, M-H, random, 95% CI 0.12-0.52; p = 0.002, I2 = 40%) but a higher rate of tumor overgrowth (RR 1.76, M-H, fixed, 95% CI 1.03-3.02; p = 0.04, I2 = 0%). Patients with CSEMSs also exhibited a higher migration rate (RR 9.33, M-H, fixed, 95% CI 2.54-34.24; p = 0.008, I2 = 0%) and a higher rate of sludge formation (RR 2.47, M-H, fixed, 95% CI 1.36-4.50; p = 0.003, I2 = 0%).

CONCLUSIONS

Our meta-analysis indicates that there is no significant difference in primary stent patency and stent dysfunction between CSEMSs and UCSEMSs during the period from primary stent insertion to primary stent dysfunction or patient death. However, when taking further management for occluded stents into consideration, CSEMSs is a better choice for patients with malignant biliary obstruction due to their removability.

Stenting in Malignant Biliary Obstruction

Decompression of the biliary system in patients with malignant biliary obstruction has been widely accepted and implemented as part of the care. Despite a wealth of literature, there remains a significant amount of uncertainty as to which approach would be most appropriate in different clinical settings. This review covers stenting of the biliary system in cases of resectable or palliative malignant biliary obstruction, potential candidates for biliary drainage, technical aspects of the procedure, as well as management of biliary stent dysfunction. Furthermore, periprocedural considerations including proper mapping of the location of obstruction and the use of antibiotics are addressed.