Endoscopic-ultrasound-guided biliary drainage with placement of electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction:Updated meta-analysis

BACKGROUND Endoscopic ultrasound-guided biliary drainage using electrocautery-enhanced(ECE)delivery of lumen-apposing metal stent(LAMS)is gradually being re-cognized as a viable palliative technique for malignant biliary obstruction after endoscopic retrograde cholangiopancreatography(ERCP)failure.However,most of the studies that have assessed its efficacy and safety were small and hetero-geneous.Prior meta-analyses of six or fewer studies that were published 2 years ago were therefore underpowered to yield convincing evidence.AIM To update the efficacy and safety of ECE-LAMS for treatment of biliary ob-struction after ERCP failure.METHODS We searched PubMed,EMBASE,and Scopus databases from the inception of the ECE technique to May 13,2022.Primary outcome measure was pooled technical success rate,and secondary outcomes were pooled rates of clinical success,re-intervention,and adverse events.Meta-analysis was performed using a random-effects model following Freeman-Tukey double-arcsine transformation in R soft-ware(version 4.1.3).RESULTS Fourteen eligible studies involving 620 participants were ultimately included.The pooled rate of technical success was 96.7%,and clinical success was 91.0%.Adverse events were reported in 17.5%of patients.Overall reinter-vention rate was 7.3%.Subgroup analyses showed results were generally consistent.CONCLUSION ECE-LAMS has favorable success with acceptable adverse events in relieving biliary obstruction when ERCP is impossible.The consistency of results across most subgroups suggested that this is a generalizable approach.

Response letter to “Acute cholangitis: Does malignant biliary obstruction vs choledocholithiasis etiology change the outcomes?” with imaging aspects

Radiological imaging findings may contribute to the differentiation of malignant biliary obstruction from choledocholithiasis in the etiology of acute cholangitis.

Endoscopic ultrasound-guided biliary drainage using electrocauteryenhanced lumen-apposing metal stent for malignant biliary obstruction:A promising procedure

In this editorial,we comment on the article by Peng et al.Palliative drainage for biliary obstruction resulting from unresectable malignant lesions includes internal and external drainage.The procedures of biliary drainage are usually guided by fluoroscopy or transcutaneous ultrasound,endoscopic ultrasound(EUS),or both.Endoscopic retrograde cholangiopancreatography(ERCP)has been primarily recommended for the management of biliary obstruction,while EUS-guided biliary drainage and percutaneous transhepatic biliary drainage(PTBD)are alternative choices for cases where ERCP has failed or is impossible.PTBD is limited by shortcomings of a higher rate of adverse events,more reinterventions,and severe complications.EUS-guided biliary drainage has a lower rate of adverse events than PTBD.EUS-guided biliary drainage with electrocautery-enhanced lumen-apposing metal stent(ECE-LAMS)enables EUS-guided biliaryenteric anastomosis to be performed in a single step and does not require prior bile duct puncture or a guidewire.The present meta-analysis showed that ECELAMS has a high efficacy and safety in relieving biliary obstruction in general,although the results of LAMS depending on the site of biliary obstruction.This study has highlighted the latest advances with a larger sample-based comprehensive analysis.

Imaging features of malignant vs stone-induced biliary obstruction:Aspects to consider

Radiological studies play a crucial role in the evaluation of patients with biliary duct obstruction,allowing for the guidance of clinical diagnosis towards a malignant or stone-induced etiology through the recognition of relevant imaging features,which must be continuously revisited given their prognostic significance.This article aims to emphasize the importance of recognizing crucial imaging aspects of malignant and stone-induced biliary obstruction.

Role of endoscopic-ultrasound-guided biliary drainage with electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction

In this editorial,we discuss the article by Peng et al in the recent issue of the World Journal of Gastrointestinal Surgery,focusing on the evolving role of endoscopicultrasound-guided biliary drainage(EUS-BD)with electrocautery lumen apposing metal stent(LAMS)for distal malignant biliary obstruction.Therapeutic endoscopy has rapidly advanced in decompression techniques,with growing evidence of its safety and efficacy surpassing percutaneous and surgical approaches.While endoscopic retrograde cholangiopancreatography(ERCP)has been the gold standard for biliary decompression,its failure rate approaches 10.0%,prompting the exploration of alternatives like EUS-BD.This random-effects meta-analysis demonstrated high technical and clinical success of over 90.0% and an adverse event rate of 17.5%,mainly in the form of stent dysfunction.Outcomes based on stent size were not reported but the majority used 6 mm and 8 mm stents.As the body of literature continues to demonstrate the effectiveness of this technique,the challenges of stent dysfunction need to be addressed in future studies.One strategy that has shown promise is placement of double-pigtail stents,only 18% received the prophylactic intervention in this study.We expect this to improve with time as the technique continues to be refined and standardized.The results above establish EUS-BD with LAMS as a reliable alternative after failed ERCP and considering EUS to ERCP upfront in the same session is an effective strategy.Given the promising results,studies must explore the role of EUS-BD as first-line therapy for biliary decompression.

Magnetic compression anastomosis to restore biliary tract continuity after obstruction following major abdominal trauma:A case report

BACKGROUND The combination of magnetic compression anastomosis(MCA)and endoscopy has been used to treat biliary stricture after liver transplantation.However,its use for the treatment of complex biliary obstruction after major abdominal trauma has not been reported.This case report describes the successful use of MCA for the treatment of biliary obstruction resulting from major abdominal trauma.A 23-year-old man underwent major abdominal surgery(repair of liver rupture,right half colon resection,and ileostomy)following a car accident one year ago.The abdominal drainage tube,positioned at the Winslow foramen,was draining approximately 600-800 mL of bile per day.During the two endoscopic retrograde cholangiopancreatography procedures,the guide wire was unable to enter the common bile duct,which prevented placement of a biliary stent.MCA combined with endoscopy was used to successfully achieve magnetic anastomosis of the peritoneal sinus tract and duodenum,and then a choledochoduodenal stent was placed.Finally,the external biliary drainage tube was removed.The patient achieved internal biliary drainage leading to the removal of the external biliary drainage tube,which improved the quality of life.CONCLUSION Magnetic compression technique can be used for the treatment of complex biliary obstruction with minimal operative trauma.

Efficacy and safety of percutaneous transhepatic biliary radiofrequency ablation in patients with malignant obstructive jaundice

BACKGROUND Percutaneous transhepatic cholangiodrainage(PTCD)and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients with unresectable malignant obstructive jaundice,yet the safety and effect of endobiliary radiofrequency ablation(EB-RFA)combined PTCD is rarely reported,in this article,we report our experience of EB-RFA combined PTCD in such patients.AIM To retrospectively study the efficacy and safety of EB-RFA combined PTCD in patients with unresectable malignant obstructive jaundice.METHODS Patients with unresectable malignant obstructive jaundice treated with EB-RFA under PTCD were selected,the bile ducts of the right posterior lobe was selected as the target bile ducts in all cases.The general conditions of all patients,preoperative tumour markers,total bilirubin(TBIL),direct bilirubin(DBIL),albumin(ALB),alkaline phosphatase(ALP),and glutamyl transferase(GGT)before and on the 7th day after the procedure,as well as perioperative complications,stent patency time and patient survival were recorded.RESULTS All patients successfully completed the operation,TBIL and DBIL decreased significantly in all patients at the 7th postoperative day(P=0.009 and 0.006,respectively);the values of ALB,ALP and GGT also decreased compared with the preoperative period,but the difference was not statistically significant.Perioperative biliary bleeding occurred in 2 patients,which was improved after transfusion of blood and other conservative treatments,pancreatitis appeared in 1 patient after the operation,no serious complication and death happened after operation.Except for 3 patients with loss of visits,the stent patency rate of the remaining 14 patients was 100%71%and 29%at the 1^(st),3^(rd),and 6^(th)postoperative months respectively,with a median survival of 4 months.CONCLUSION EB-RFA under PTCD in patients with unresectable malignant obstructive jaundice has a satisfactory therapeutic effect and high safety,which is worthy of further clinical practice.

Endoscopic ultrasound-guided biliary drainage vs percutaneous transhepatic bile duct drainage in the management of malignant obstructive jaundice

BACKGROUND Malignant obstructive jaundice(MOJ)is a condition characterized by varying degrees of bile duct stenosis and obstruction,accompanied by the progressive development of malignant tumors,leading to high morbidity and mortality rates.Currently,the two most commonly employed methods for its management are percutaneous transhepatic bile duct drainage(PTBD)and endoscopic ultrasound-guided biliary drainage(EUS-BD).While both methods have demonstrated favorable outcomes,additional research needs to be performed to determine their relative efficacy.To compare the therapeutic effectiveness of EUS-BD and PTBD in treating MOJ.METHODS This retrospective analysis,conducted between September 2015 and April 2023 at The Third Affiliated Hospital of Soochow University(The First People’s Hospital of Changzhou),involved 68 patients with MOJ.The patients were divided into two groups on the basis of surgical procedure received:EUS-BD subgroup(n=33)and PTBD subgroup(n=35).Variables such as general data,preoperative and postoperative indices,blood routine,liver function indices,myocardial function indices,operative success rate,clinical effectiveness,and complication rate were analyzed and compared between the subgroups.RESULTS In the EUS-BD subgroup,hospital stay duration,bile drainage volume,effective catheter time,and clinical effect-iveness rate were superior to those in the PTBD subgroup,although the differences were not statistically significant(P>0.05).The puncture time for the EUS-BD subgroup was shorter than that for the PTBD subgroup(P<0.05).Postoperative blood routine,liver function index,and myocardial function index in the EUS-BD subgroup were significantly lower than those in the PTBD subgroup(P<0.05).Additionally,the complication rate in the EUS-BD subgroup was lower than in the PTBD subgroup(P<0.05).CONCLUSION EUS-BD may reduce the number of punctures,improve liver and myocardial functions,alleviate traumatic stress,and decrease complication rates in MOJ treatment.

Acute cholangitis: Does malignant biliary obstruction vs choledocholithiasis etiology change the clinical presentation and outcomes?

BACKGROUND Whether clinical outcomes of acute cholangitis(AC)vary by etiology is unclear.AIM To compare outcomes in AC caused by malignant biliary obstruction(MBO)and common bile duct stones(CBDS).METHODS This retrospective study included 516 patients undergoing endoscopic retrograde cholangiopancreatography(ERCP)due to AC caused by MBO(MBO group,n=56)and CBDS(CBDS group,n=460).Clinical and laboratory parameters were compared between the groups.Propensity score matching(PSM)created 55 matched pairs.Confounders used in the PSM analysis were age,sex,time to ERCP,and technical success of ERCP.The primary outcome comparison was 30-d mortality.The secondary outcome comparisons were intensive care unit(ICU)admission rate,length of hospital stay(LOHS),and 30-d readmission rate.RESULTS Compared with the CBDS group,the MBO group had significantly lower body temperature,percentage of abnormal white blood cell counts,and serum levels of aspartate aminotransferase,alanine aminotransferase,and creatinine.Body temperature,percent abnormal white blood cell count,and serum aspartate aminotransferase levels remained significantly lower in the MBO group in the PSM analysis.Platelet count,prothrombin time/international normalized ratio,and serum levels of alkaline phosphatase and total bilirubin were significantly higher in the MBO group.The MBO group had a significantly higher percentage of severe AC(33.9%vs 22.0%,P=0.045)and received ERCP later(median,92.5 h vs 47.4 h,P<0.001).However,the two differences were not found in the PSM analysis.The 30-d mortality(5.4%vs 0.7%,P=0.019),ICU admission rates(12.5%vs 4.8%,P=0.028),30-d readmission rates(23.2%vs 8.0%,P<0.001),and LOHS(median,16.5 d vs 7.0 d,P<0.001)were significantly higher or longer in the MBO group.However,only LOHS remained significant in the PSM analysis.Multivariate analysis revealed that time to ERCP and multiple organ dysfunction were independent factors associated with 30-d mortality.CONCLUSION MBO patients underwent ERCP later and thus had a worse prognosis than CBDS patients.Therefore,clinicians should remain vigilant in MBO patients with clinically suspected AC,and perform ERCP for biliary drainage as soon as possible.

Effectiveness of a new approach to minimally invasive surgery in palliative treatment of patients with distal malignant biliary obstruction

BACKGROUND Palliative endoscopic biliary drainage is the primary treatment option for the management of patients with jaundice which results from distal malignant biliary obstruction(DMBO).In this group of patients,decompression of the bile duct(BD)allows for pain reduction,symptom relief,chemotherapy administration,improved quality of life,and increased survival rate.To reduce the unfavorable effects of BD decompression,minimally invasive surgical techniques require continuous improvement.AIM To develop a technique for internal-external biliary-jejunal drainage(IEBJD)and assess its effectiveness in comparison to other minimally invasive procedures in the palliative treatment of patients with DMBO.METHODS A retrospective analysis of prospectively collected data was performed,which included 134 patients with DMBO who underwent palliative BD decompression.Biliary-jejunal drainage was developed to divert bile from the BD directly into the initial loops of the small intestine to prevent duodeno-biliary reflux.IEBJD was carried out using percutaneous transhepatic access.Percutaneous transhepatic biliary drainage(PTBD),endoscopic retrograde biliary stenting(ERBS),and internal-external transpapillary biliary drainage (IETBD) were used for the treatment of studypatients. Endpoints of the study were the clinical success of the procedure, the frequency andnature of complications, and the cumulative survival rate.RESULTSThere were no significant differences in the frequency of minor complications between the studygroups. Significant complications occurred in 5 (17.2%) patients in the IEBJD group, in 16 (64.0%)in the ERBS group, in 9 (47.4%) in the IETBD group, and in 12 (17.4%) in the PTBD group.Cholangitis was the most common severe complication. In the IEBJD group, the course ofcholangitis was characterized by a delayed onset and shorter duration as compared to other studygroups. The cumulative survival rate of patients who underwent IEBJD was 2.6 times higher incomparison to those of the PTBD and IETBD groups and 20% higher in comparison to that of theERBS group.CONCLUSIONIEBJD has advantages over other minimally invasive BD decompression techniques and can berecommended for the palliative treatment of patients with DMBO.

Different percutaneous transhepatic biliary stent placements and catheter drainage in the treatment of middle and low malignant biliary obstruction

BACKGROUND For cases of middle and low biliary obstruction with left and right hepatic duct dilatation,the type of approach and whether different approaches affect the difficulty of puncture operation and intraoperative and postoperative complications have not been discussed in detail.AIM To compare the efficacy of different percutaneous transhepatic biliary stent placements and catheter drainage in treating middle and low biliary obstruction.METHODS A retrospective analysis was performed on the medical records of 424 patients with middle and low biliary obstruction who underwent percutaneous liver puncture biliary stent placement and catheter drainage at the Department of Interventional Radiology,Shaanxi Provincial People’s Hospital between March 2016 and March 2022.Based on the puncture path,patients were categorized into two groups:Subxiphoid left hepatic lobe approach group(Group A,224 cases)and right intercostal,right hepatic lobe approach group(Group B,200 cases).Liver function improvement,postoperative biliary bleeding incidence,postoperative pain duration,and abdominal effusion leakage around the drainage tube were compared between the two groups at 3 d and 1 wk after the surgery.Patient survival time was recorded during follow-up.RESULTS All 424 surgeries were successful without adverse events.Group A comprised 224 cases,and Group B had 200 cases.There was no statistically significant difference in basic data between Group A and Group B(P>0.05).No significant difference in postoperative biliary bleeding incidence was observed between the groups(P>0.05).The decreased rates for total bilirubin(Group A:69.23±4.50,Group B:63.79±5.65),direct bilirubin(Group A:79.30±11.19,Group B:63.62±5.64),and alkaline phosphatase(Group A:60.51±12.23,Group B:42.68±23.56)in the 1st wk after surgery were significantly faster in Group A than in Group B.The decreased rate of gamma-glutamyl transpeptidase was also significantly faster in Group A at both 3 d(Group A:40.56±10.32,Group B:32.22±5.12)and 1 wk(Group A:73.19±7.05,Group B:58.81±18.98)after surgery(P<0.05).Group A experienced significantly less peritoneal effusion leakage around the drainage tube than Group B(P<0.05).The patient survival rate was higher in Group A compared to Group B(P<0.05).CONCLUSION In treating jaundice patients with middle and low biliary obstruction,a percutaneous left liver puncture demonstrated better clinical efficacy than a percutaneous right liver puncture.

Metal stent implantation for palliation of malignant biliary obstruction-a report of 57 cases

AIMS To report the first experience in China in the treatment of malignant biliary obstruction with expand- able metal stent which allows the insertion of an endo- prosthesis as large as one cm in diameter. METHODS Between April 1994 and May 1996,we implanted expandable metal stents in 57 patients with incurable malignant biliary obstruction,among whom 54 underwent endoscopic procedure and the other 3 re- ceived percutaneous transhepatic placement. RESULTS Insertion of the stent following guidewire positioning was successful in 95% of the patients. Two patients developed cholangitis after stent insertion and were successfully treated with conservative treatment. The jaundice was eliminated completely in 21 cases and markedly decreased in 23 cases within 2 weeks af- ter placement of the stent. Nine patients,however, had late cholangitis due to stent failure after a median interval of 14 days. Twenty-three cases underwent na- sobiliary transient drainage and 3 underwent plastic stent transient drainage prior to metal stent insertion. Transient drainage was believed to have the advan- tages of drainage pre-assessment and infection controlling. CONCLUSIONS Our results show that expandable metal stent is suitable for the irresectable malignant choledochal stenosis. It can eliminate the jaundice and improve the patient's life quality. To get the highest benefit,however,the indication should be strictly selected. And to get long-term patency,the proximal and distal end of the stent proceeding the tumor should be no shorter than 2cm. In the case of hilar cancer, Bismuth classification is greatly helpful for the choice of drainage site.

The Cost-effectiveness Analysis of Percutaneous Transhepatic Metal Versus Plastic Biliary Stent Implantation for Treating Malignant Biliary Obstruction (Multiple Center Investigation)

Objective: To compare metal versus plastic biliary stent implantation for treatment of malignant biliary obstruction in cost-effectiveness ratio (CER). Methods: Percutaneous transhepatic self-expandable metal stent (MS, n=61) or 10F plastic stent (PS, n=34) implantation was performed in 95 patients with malignant biliary obstruction in three hospitals of Guangdong province. All patients were followed up until death or at least one year after the procedure. Kaplan-Meier analysis was used to compare the survival and stent patency rates of the patients in the two groups. CERs of two groups were calculated. The main indexes were CERsurvival period (total cost/median survival period), CERpatency period (total cost/median patency period). Results: The total costs of treatment were 53177±3139 yuan (RMB) in MS group and 42564±4950 yuan (RMB) in PS group respectively (P>0.05). CER in MS group was superior to that in PS group (CERsurvival period was 237.4 yuan /d vs 452.6 yuan /d, respectively; CERpatency period was 231.2 yuan /d vs 472.9 yuan /d, respectively). Conclusion: The metal stent implantation is superior to the plastic stent in the CER for treatment of malignant biliary obstruction.

Multicenter study of endoscopic preoperative biliary drainage for malignant distal biliary obstruction

AIM: To determine the optimal method of endoscopic preoperative biliary drainage for malignant distal biliary obstruction.METHODS: Multicenter retrospective study was conducted in patients who underwent plastic stent (PS) or nasobiliary catheter (NBC) placement for resectable malignant distal biliary obstruction followed by surgery between January 2010 and March 2012. Procedure-related adverse events, stent/catheter dysfunction (occlusion or migration of PS/NBC, development of cholangitis, or other conditions that required repeat endoscopic biliary intervention), and jaundice resolution (bilirubin level &#x0003c; 3.0 mg/dL) were evaluated. Cumulative incidence of jaundice resolution and dysfunction of PS/NBC were estimated using competing risk analysis. Patient characteristics and preoperative biliary drainage were also evaluated for association with the time to jaundice resolution and PS/NBC dysfunction using competing risk regression analysis.RESULTS: In total, 419 patients were included in the study (PS, 253 and NBC, 166). Primary cancers included pancreatic cancer in 194 patients (46%), bile duct cancer in 172 (41%), gallbladder cancer in three (1%), and ampullary cancer in 50 (12%). The median serum total bilirubin was 7.8 mg/dL and 324 patients (77%) had &#x02265; 3.0 mg/dL. During the median time to surgery of 29 d [interquartile range (IQR), 30-39 d]. PS/NBC dysfunction rate was 35% for PS and 18% for NBC [Subdistribution hazard ratio (SHR) = 4.76; 95%CI: 2.44-10.0, P &#x0003c; 0.001]; the pig-tailed tip was a risk factor for PS dysfunction. Jaundice resolution was achieved in 85% of patients and did not depend on the drainage method (PS or NBC).CONCLUSION: PS has insufficient patency for preoperative biliary drainage. Given the drawbacks of external drainage via NBC, an alternative method of internal drainage should be explored.

New antireflux plastic stent for patients with distal malignant biliary obstruction

BACKGROUND Endoscopic biliary stenting is a well-established palliative treatment for patients with unresectable distal malignant biliary obstruction(MBO). However, the main problem with stent placement is the relatively short duration of stent patency.Although self-expanding metal stents(SEMSs) have a longer patency period than plastic stents(PSs), the higher costs limit the wide use of SEMSs. A PS with an antireflux valve is an attractive idea to prolong stent patency, but no ideal design for an antireflux PS(ARPS) has been proposed. We developed a new ARPS with a "duckbilled" valve attached to the duodenal end of the stent.AIM To compare the patency of ARPSs with that of traditional PSs(TPSs) in patients with unresectable distal MBO.METHODS We conducted a single-center, prospective, randomized, controlled, double-blind study. This study was conducted at the West China Hospital of Sichuan University. Consecutive patients with extrahepatic MBO were enrolled prospectively. Eligible patients were randomly assigned to receive either an ARPS or a TPS. Patients were followed by clinic visits or telephone interviews every 1-2 mo until stent exchange, death, or the final study follow-up in October 2018. The primary outcome was the duration of stent patency. Secondary outcomes included the rate of technical success, the rate of clinical success,adverse events, and patient survival.RESULTS Between February 2016 and December 2017, 38 patients were randomly assigned to two groups, with 19 patients in each group, to receive ARPSs or TPSs. Stent insertion was technically successful in all patients. There were no significant differences between the two groups in the rates of clinical success or the rates of early or late adverse events(P = 0.660, 1.000, and 1.000, respectively). The median duration of stent patency in the ARPS group was 285 d [interquartile range(IQR),170], which was significantly longer than that in the TPS group(median, 130 d;IQR, 90, P = 0.005). No significant difference in patient survival was noted between the two groups(P = 0.900).CONCLUSION The new ARPS is safe and effective for the palliation of unresectable distal MBO,and has a significantly longer stent patency than a TPS.

Percutaneous transhepatic metal versus plastic biliary stent in treating malignant biliary obstruction: a multiple center investigation

OBJECTIVE: To compare the efficacy of metal versus plastic biliary stent implantation in the treatment of malignant biliary obstruction. METHODS: Percutaneous transhepatic self-expandable metal stent (MS, n=61) and 10F plastic stent (PS, n=34) were placed in 95 patients with malignant biliary obstruction in three hospitals of Guangdong province. All patients were followed up until death or at least one year after the procedure. Kaplan-Meier analysis was used to compare the survival of the patients and the rates of stent patency. RESULTS: The 30-day mortality rate was lower in the MS group (6/61, 9.8%) than in the PS group (9/34, 26.5%, P<0.05). The 30-day reobstruction rate and the complication rate were 15.0%, 16.4% in the MS group and 32. 4%, 29. 4% in the PS group, respectively (P<0. 01). The median patency period of stents and median survival period of the patients were 230 days, 224 days in the MS group and 90 days, 94 days in the PS group, respectively (P<0. 01). CONCLUSION: Metal stent is clinically superior to plastic stent in the treatment of malignant biliary obstruction.

Randomized trial in malignant biliary obstruction:Plastic vs partially covered metal stents

AIM:To compare efficacy and complications of par-tially covered self-expandable metal stent(pcSEMS)to plastic stent(PS)in patients treated for malignant,infrahilar biliary obstruction.METHODS:Multicenter prospective randomized clinical trial with treatment allocation to a pcWallstent(SEMS)or a 10 French PS.Palliative patients aged≥18,for infrahilar malignant biliary obstruction and a Karnofsky performance scale index>60%from 6 participating North American university centers.Primary endpoint was time to stent failure,with secondary outcomes of death,adverse events,Karnofsky performance score and short-form-36 scale administered on a three-monthly basis for up to 2 years.Survival analyses were performed for stent failure and death,with Cox proportional hazards regression models to determine significant predictive characteristics.RESULTS:Eighty-five patients were accrued over 37mo,42 were randomized to the SEMS group and 83patients were available for analyses.Time to stent failure was 385.3±52.5 d in the SEMS and 153.3±19.8 d in the PS group,P=0.006.Time to death did not differ between groups(192.3±23.4 d for SEMS vs211.5±28.0 d for PS,P=0.70).The only significant predictor was treatment allocation,relating to the time to stent failure(P=0.01).Amongst other measured outcomes,only cholangitis differed,being more common in the PS group(4.9%vs 24.5%,P=0.029).The small number of patients in follow-up limits longitudinal assessments of performance and quality of life.From an initially planned 120 patients,only 85 patients were recruited.CONCLUSION:Partially covered SEMS result in a longer duration till stent failure without increased complication rates,yet without accompanying measurable benefits in survival,performance,or quality of life.

Endoscopic ultrasound-guided biliary drainage with placement of a fully covered metal stent for malignant biliary obstruction

AIM:To determine the utility of endoscopic ultrasoundguided biliary drainage(EUS-BD)with a fully covered self-expandable metal stent for managing malignant biliary stricture. METHODS:We collected data from 13 patients who presented with malignant biliary obstruction and underwent EUS-BD with a nitinol fully covered selfexpandable metal stent when endoscopic retrograde cholangiopancreatography(ERCP)fails.EUS-guided choledochoduodenostomy(EUS-CD)and EUS-guided hepaticogastrostomy(EUS-HG)was performed in 9 patients and 4 patients,respectively. RESULTS:The technical and functional success rate was 92.3%(12/13)and 91.7%(11/12),respectively. Using an intrahepatic approach(EUS-HG,n=4),there was mild peritonitis(n=1)and migration of the metal stent to the stomach(n=1).With an extrahepatic approach(EUS-CD,n=10),there was pneumoperitoneum(n=2),migration(n=2),and mild peritonitis (n=1).All patients were managed conservatively with antibiotics.During follow-up(range,1-12 mo),there was re-intervention(4/13 cases,30.7%)necessitated by stent migration(n=2)and stent occlusion(n=2). CONCLUSION:EUS-BD with a nitinol fully covered self-expandable metal stent may be a feasible and effective treatment option in patients with malignant biliary obstruction when ERCP fails.

Biliary phytobezoar resulting in intestinal obstruction

Phytobezoar is the most common type of bezoar.It is composed of indigestible vegetable matter and is usually found in the stomach.Biliary phytobezoar is extremely rare and difficult to diagnose preoperatively.The pathogenesis is not clear,and there have been only a few reports of biliary bezoars associated with sphincteric impairmentat the ampulla of Vater.Here,we present a report of biliary bezoar that resulted in jejunal obstruction.We were unable to identifythe bezoar in the extrahepatic bile duct until it obstructed the small bowel lumen.To our knowledge,this is the first report of small bowel obstruction resulting frommigration of a biliary bezoar.

New 14-mm diameter Niti-S biliary uncovered metal stent for unresectable distal biliary malignant obstruction

AIM To investigate whether an uncovered self-expandable metal stent(UCSEMS) with a large diameter could prevent recurrent biliary obstruction(RBO).METHODS Thirty-eight patients with malignant biliary obstruction underwent treatment with an UCSEMS with a 14-mm diameter(Niti-S 14). Retrospectively, we evaluated technical and functional success rate, RBO rate, time to RBO, survival time, and adverse events in these patients.RESULTS Stent placement success and functional success were achieved in all patients. Two patients(5.3%) had RBO due to tumor ingrowth or overgrowth. The median time to RBO was 190(range, 164-215) d. The median survival time was 120(range, 18-502) d. The 6-mo non-RBO rate was 91%. Other adverse events other than RBO occurred as follows: Acute cholecystitis, post-ERCP pancreatitis, hemobilia, and fever without exacerbation of liver injury, and liver abscess in 4(10.3%), 3(7.9%), 2(5.3%), 1(2.6%), and 1(2.6%), respectively. Migration of the stents was not observed.CONCLUSION Niti-S 14 is considered to be a preferable metal stent because of a low rate of RBO with no migration.