Unilateral versus Bilateral Endoscopic Nasobiliary Drainage and Subsequent Metal Stent Placement for Unresectable Malignant Hilar Obstruction: A Multicenter Randomized Controlled Trial.

(1) Background: Endoscopic management of hilar biliary obstruction is still challenging. Compared with unilateral drainage, bilateral drainage could preserve larger functional liver volume and potentially improve clinical outcomes. To evaluate the effectiveness of bilateral drainage, we conducted this multicenter randomized controlled study. (2) Methods: Patients with unresectable malignant hilar biliary obstruction were assigned to unilateral or bilateral group. At first, patients underwent endoscopic nasobiliary drainage (ENBD), and subsequently underwent self-expandable metallic stent (SEMS) deployment. Primary outcomes were the functional success rate of ENBD and time to recurrent biliary obstruction (TRBO) after SEMS deployment. (3) Results: During the study period, 38 and 39 patients were enrolled in the unilateral and bilateral groups. The functional success rate was similar in the uni- and bi-ENBD group (57% vs. 56%; p = 0.99), but the rate of additional drainage was higher in uni-ENBD group. Although TRBO and overall survival time after SEMS deployment were not different between the groups (p = 0.11 and 0.78, respectively), the incidence of early adverse events tended to be higher in the bi-SEMS group (5.3% vs. 28%; p = 0.11). (4) Conclusions: Our study failed to demonstrate the superiority of bilateral over unilateral biliary drainage in terms of functional success rate and TRBO.

Multicenter randomized trial of endoscopic papillary large balloon dilation without sphincterotomy versus endoscopic sphincterotomy for removal of bile duct stones: MARVELOUS trial.

BACKGROUND : Endoscopic papillary large balloon dilation (EPLBD) has been increasingly used for the management of large common bile duct (CBD) stones. Although EPLBD is often preceded by endoscopic sphincterotomy (EST), EPLBD alone without EST has been increasingly reported as an alternative to EST for large CBD stones. METHODS : This multicenter randomized trial was conducted at 19 Japanese institutions to compare the efficacy and safety of EPLBD alone versus EST for the removal of large (≥ 10 mm) CBD stones. The primary end point was complete stone removal in a single session. The secondary end points included: overall complete stone removal, lithotripsy use, procedure time, adverse events, and cost. RESULTS: 171 patients with large CBD stones were included in the analysis. The rate of single-session complete stone removal was significantly higher in the EPLBD-alone group than in the EST group (90.7 % vs. 78.8 %; P = 0.04). Lithotripsy use was significantly less frequent in the EPLBD group than in the EST group (30.2 % vs. 48.2 %; P = 0.02). The rates of early adverse events were comparable between the two groups: rates of overall adverse events were 9.3 % vs. 9.4 % and of pancreatitis were 4.7 % vs. 5.9 % in the EPLBD and EST groups, respectively. The procedure costs were $1442 vs. $1661 in the EPLBD and EST groups, respectively (P = 0.12). CONCLUSION : EPLBD without EST for the endoscopic treatment of large CBD stones achieved a significantly higher rate of complete stone removal in a single session compared with EST, without increasing adverse events.

A randomized-controlled trial of early endotherapy versus wait-and-see policy for mild symptomatic pancreatic stones in chronic pancreatitis.

BACKGROUND: Although surgical or endoscopic treatment is effective for pain control in symptomatic calcified chronic pancreatitis, it is still unknown whether early intervention in mild symptomatic pancreatic stones would reduce the frequency of acute exacerbation and improve long-term outcomes. The aim of this randomized-controlled trial was to explore the efficacy of early endotherapy for mild symptomatic pancreatic stones in comparison with the wait-and-see policy. MATERIALS AND METHODS: Patients with mild symptoms because of pancreatic stones were assigned randomly to the endotherapy or the wait-and-see group. The wait-and-see group received endotherapy only when they developed refractory exacerbation or intractable pain. The primary outcome was the cumulative incidence of intolerable pain attacks and acute exacerbation. The secondary outcomes were the development of pancreatic insufficiency and the progression of pancreatic atrophy. RESULTS: A total of 20 patients were enrolled between March 2008 and March 2011. The study was terminated prematurely because of the poor patient enrollment. Early endotherapy tended to reduce the cumulative incidence of pain attacks and exacerbation, (P=0.17) with the composite incidence of pain attacks and exacerbation of 30% in the endotherapy group and 60% in the wait-and-see group. There were no significant differences in terms of diabetic status and the presence of steatorrhea. The thickness of the pancreas decreased significantly in the wait-and-see group (9.2-6.8 mm, P=0.041), but not in the endotherapy group (8.7-9.0 mm, P=0.60). CONCLUSION: In a small group of patients, early endotherapy in mild symptomatic chronic pancreatitis was associated with a trend toward a minor number of acute attacks and atrophy progression of the pancreas.

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).

Early pancreatic stent placement in wire-guided biliary cannulation: A multicenter retrospective study.

BACKGROUND AND AIM: Guidewire insertion to a pancreatic duct under wire-guided cannulation (WGC) during endoscopic retrograde cholangiopancreatography (ERCP) is associated with a high incidence of post-ERCP pancreatitis (PEP). Pancreatic stent placement followed by WGC (PS-WGC) is considered for these cases to reduce PEP. This study was aimed to examine the effectiveness of PS-WGC compared with repeated WGC. METHODS: The consecutive data of patients without history of ERCP who underwent ERCP for biliary intervention were retrospectively collected from five centers. Patients without guidewire insertion to the pancreatic duct were excluded. Pancreatic stent was immediately placed after guidewire insertion to the pancreatic duct in the PS-WGC group. The association between the method of biliary cannulation (PS-WGC or repeated WGC) and PEP was analyzed using multivariable logistic regression model. RESULTS: A total of 590 patients (183 in the PS-WGC and 407 in the repeated WGC group) were included. PS-WGC decreased PEP (8.7% vs 19%, P = 0.001) and improved its severity (moderate and severe PEP; 2.2% vs 6.4%, P = 0.04) compared with repeated WGC. PS-WGC was associated with reduction of PEP in the multivariable model (Odds ratio 0.31, P < 0.001). The rates of difficult cannulation and overall successful biliary cannulation were not different between the two groups (66% vs 70%, P = 0.39 and 98% vs 96%, P = 0.21 in the PS-WGC and repeated WGC group, respectively). CONCLUSIONS: Pancreatic stent placement followed by WGC reduced PEP in patients with guidewire insertion to the pancreatic duct during WGC for native papilla compared with repeated WGC.

A Multicenter Open-Label Randomized Controlled Trial of Pancreatic Enzyme Replacement Therapy in Unresectable Pancreatic Cancer.

OBJECTIVE: Exocrine pancreatic insufficiency may impair the nutritional status in pancreatic cancer (PC), but the role of pancreatic enzyme replacement therapy (PERT) is not fully evaluated. Therefore, we conducted this multicenter open-label randomized controlled trial to evaluate the role of PERT in PC patients. METHODS: Patients with unresectable PC receiving chemotherapy were randomly assigned to pancrelipase and nonpancrelipase groups. Patients in the pancrelipase group took oral pancrelipase of 48,000 lipase units per meal. N-benzoyl-tryrosyl para-aminobenzoic acid (NBT-PABA) test was performed at baseline. Our primary endpoint was change in body mass index (BMI) at 8 weeks. Secondary endpoints were change in other nutritional status at 8 weeks and overall survival. RESULTS: A total of 88 patients were enrolled between May 2014 and May 2016. The NBT-PABA test was lower than the normal range in 90%. There were no significant differences in change in BMI at 8 weeks: 0.975 and 0.980 in the pancrelipase and the nonpancrelipase groups, respectively (P = 0.780). The other nutritional markers were also comparable. The median overall survival was 19.0 and 12.0 months (P = 0.070). CONCLUSIONS: In this randomized controlled trial, pancrelipase failed to improve the change in BMI at 8 weeks in PC patients receiving chemotherapy.

Preoperative biliary drainage using a fully covered self-expandable metallic stent for pancreatic head cancer: A prospective feasibility study.

Background/Aims: The role of endoscopic preoperative biliary drainage (PBD) for pancreatic head cancer is controversial because of the high incidence of stent occlusion before surgery. This study was performed to evaluate the feasibility and safety of PBD using a fully covered self-expandable metallic stent (FCSEMS). Patients and Methods: This multicenter prospective study involved 26 patients treated for pancreatic head cancer with distal bile duct obstruction from April 2011 to March 2013. An FCSEMS was endoscopically placed in 24 patients. Among these, 7 patients were diagnosed with unresectable cancer, and 17 underwent surgery at a median of 18 days after FCSEMS placement. The main outcome measure was preoperative and postoperative adverse events. Results: Two adverse events (cholecystitis and insufficient resolution of jaundice) occurred between FCSEMS placement and surgery (12%). Postoperative adverse events occurred in eight patients (47%). The cumulative incidence of stent-related adverse events 4 and 8 weeks after FCSEMS placement among the 24 patients who underwent this procedure were 19%. Conclusions: PBD using an FCSEMS is feasible in patients with resectable pancreatic head cancer. Placement of an FCSEMS can be an alternative PBD technique when surgery without delay is impossible. A larger randomized controlled trial is warranted.

A 19-Gauge Histology Needle Versus a 19-Gauge Standard Needle in Endoscopic Ultrasound-Guided Fine-Needle Aspiration for Solid Lesions: A Multicenter Randomized Comparison Study (GREATER Study).

BACKGROUND: The necessity of histological analysis is increasing. A 19-gauge histology needle (PC19) in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has recently been developed and has shown high yields of tissue acquisition and histological diagnosis. AIMS: To compare the histological diagnostic yield in single-pass EUS-FNA for solid lesions using PC19 and a standard 19-gauge needle (EC19). PATIENTS AND METHODS: Consecutive patients with solid lesions were enrolled and underwent one pass with each of PC19 and EC19 for EUS-FNA with the randomized order of the needles. The primary endpoint was the histological diagnostic accuracy. The secondary endpoints were the feasibility, yield of histological core, cytological and overall diagnostic accuracies, and adverse events. Subgroup analysis was performed for the optimal situation with PC19. RESULTS: Of the 115 patients, 110 underwent EUS-FNA and five were excluded. EUS-FNA was performed from the esophagus in four, stomach in 80, or duodenum in 26. The final diagnosis was malignancy in 100 and benign in 10. The feasibility was 98.2 and 97.3% with PC19 and EC19, respectively (p = 1.00). The rate of presence of a histological core and the histological, cytological, and overall diagnostic accuracies for PC19 versus EC19 were 84.6 versus 80.9% (p = 0.593), 83.6 versus 73.6% (p = 0.099), 63.6 versus 56.4% (p = 0.335), and 90.0 versus 79.1% (p = 0.039), respectively. PC19 was favored in the trans-esophageal/gastric approaches to obtain a histological diagnosis (p = 0.013). Adverse events were observed in four patients. CONCLUSION: Single-pass EUS-FNA with PC19 was feasible and showed significantly higher overall diagnostic accuracy and an increased tendency towards histological diagnostic accuracy, especially with trans-esophageal/gastric FNA.

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).

Multicenter retrospective and comparative study of 5-minute versus 15-second endoscopic papillary balloon dilation for removal of bile duct stones.

BACKGROUND AND STUDY AIMS: Endoscopic papillary balloon dilation (EPBD) is a method of bile duct stone removal that has a better long-term outcome but a high risk of post-ERCP pancreatitis (PEP). Recent studies have suggested that 5-minute EPBD can reduce the incidence of PEP. This study aimed to examine the safety and effectiveness of longer duration EPBD compared with shorter duration EPBD (5 minutes vs. 15 seconds after disappearance of the waist of a dilation catheter). PATIENTS AND METHODS: Patients without a history of endoscopic sphincterotomy or EPBD who underwent EPBD to remove bile duct stones were selected retrospectively from five centers. The incidence of PEP, other early adverse events, and outcomes of EPBD were compared between the groups. A multivariable analysis of risk factors for PEP was performed. RESULTS: A total of 607 patients (157 and 450 in the 5-minute and 15-second EPBD groups, respectively) were included. There were no statistically significant differences between the groups in terms of the incidence of PEP (8.3 % and 8.9 % in the 5-minute and 15-second EPBD groups, respectively; P  = 0.871) and the incidence of overall early adverse events ( P  = 0.999). Although 5-minute EPBD elongated the procedure time (45 vs. 37 minutes, P  < 0.001), it increased the rate of complete stone removal during a single session ( P  < 0.001) and decreased the use of lithotripsy ( P  < 0.001). CONCLUSIONS: Compared with 15-second EPBD, 5-minute EPBD did not reduce the incidence of PEP.

A Novel Partially Covered Self-Expandable Metallic Stent with Proximal Flare in Patients with Malignant Gastric Outlet Obstruction.

BACKGROUND/AIMS: Endoscopic placement of self-expandable metal stents (SEMSs) has emerged as a palliative treatment for malignant gastric outlet obstruction (GOO). Although covered SEMSs can prevent tumor ingrowth, frequent migration of covered SEMSs may offset their advantages in preventing tumor ingrowth. METHODS: We conducted this multicenter, single-arm, retrospective study at six tertiary referral centers to evaluate the safety and efficacy of a partially covered SEMS with an uncovered large-bore flare at the proximal end as an antimigration system in 41 patients with symptomatic malignant GOO. The primary outcome was clinical success, and the secondary outcomes were technical success, stent dysfunction, adverse events, and survival after stent placement. RESULTS: The technical and clinical success rates were 100% and 95%, respectively. Stent dysfunctions occurred in 17 patients (41%), including stent migration in nine (23%), tumor ingrowth in one (2%), and tumor overgrowth in four (10%). Two patients (5%) developed adverse events: one pancreatitis and one perforation. No procedure-related death was observed. CONCLUSIONS: A novel partially covered SEMS with a large-bore flare proximal end was safe and effective for malignant GOO but failed to prevent stent migration. Further research is warranted to develop a covered SEMS with an optimal antimigration system.

Gemcitabine and S-1 versus gemcitabine and cisplatin treatment in patients with advanced biliary tract cancer: a multicenter retrospective study.

Objective This study aimed to compare the safety and efficacy of the combination therapy of gemcitabine and S-1 (GS) versus gemcitabine and cisplatin (GC) in patients with advanced biliary tract cancer (BTC). Methods In this multicenter retrospective cohort study, a total of 212 patients with advanced BTC receiving GS (n = 125) or GC (n = 87) between July 2006 and August 2015 were analyzed. The primary endpoint was overall survival (OS). The secondary endpoints were progression-free survival (PFS), objective tumor response, and safety. Results Patient characteristics were well balanced between the two groups, except for tumor size (the baseline sum of the largest diameter of the tumor: 6.3 cm in the GS group vs. 8.6 cm in the GC group, p = 0.01). Although the response rate was higher in the GS group than in the GC group (28.8% vs. 10.3%, p = 0.01), the median PFS and OS were comparable between the two groups (PFS of 5.6 vs. 7.6 months, p = 0.74; OS of 12.4 vs. 9.2 months, p = 0.20, respectively). Stomatitis and skin rash were more frequently observed in the GS group, whereas anemia, thrombocytopenia, nausea, and renal toxicity were more commonly observed in the GC group. Conclusion This study demonstrates that GS and GC are similar with regard to their safety and efficacy in patients with advanced BTC. GS could serve as an alternative treatment for advanced BTC as a first-line chemotherapy.

Antireflux Metal Stent as a First-Line Metal Stent for Distal Malignant Biliary Obstruction: A Pilot Study.

BACKGROUND/AIMS: In distal malignant biliary obstruction, an antireflux metal stent (ARMS) with a funnel-shaped valve is effective as a reintervention for metal stent occlusion caused by reflux. This study sought to evaluate the feasibility of this ARMS as a first-line metal stent. METHODS: Patients with nonresectable distal malignant biliary obstruction were identified between April and December 2014 at three Japanese tertiary centers. We retrospectively evaluated recurrent biliary obstruction and adverse events after ARMS placement. RESULTS: In total, 20 consecutive patients were included. The most common cause of biliary obstruction was pancreatic cancer (75%). Overall, recurrent biliary obstruction was observed in seven patients (35%), with a median time to recurrent biliary obstruction of 246 days (range, 11 to 246 days). Stent occlusion occurred in five patients (25%), the causes of which were sludge and food impaction in three and two patients, respectively. Stent migration occurred in two patients (10%). The rate of adverse events associated with ARMS was 25%: pancreatitis occurred in three patients, cholecystitis in one and liver abscess in one. No patients experienced nonocclusion cholangitis. CONCLUSIONS: The ARMS as a first-line biliary drainage procedure was feasible. Because the ARMS did not fully prevent stent dysfunction due to reflux, further investigation is warranted.

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 < 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 ≥ 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 < 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.

Antireflux metal stent with an antimigration system for distal malignant biliary obstruction: a feasibility pilot study.

An antireflux metal stent (ARMS) for distal malignant biliary obstruction has been reported to be useful, but the effectiveness of a flared-end structure to prevent migration on ARMS remains unclear. To evaluate the feasibility of a newly designed ARMS with both ends flared, 8 patients with covered metal stent occlusion due to sludge or food impaction were enrolled. ARMS were placed successfully after endoscopic removal of the occluded stents in all patients, and no procedure-related complication was observed. The median time to recurrent biliary obstruction was 71 days. ARMS occlusion occurred in 3 (38%) patients (sludge in 2 patients and hemobilia in 1). ARMS migration occurred in 1 (13%) patient. As a late complication, cholecystitis occurred in 1 (13%) patient. In conclusion, our newly designed ARMS with an antimigration system was technically feasible and safe, and a further investigation is warranted to evaluate the effectiveness of the current antimigration system.

Early use of double-guidewire technique to facilitate selective bile duct cannulation: the multicenter randomized controlled EDUCATION trial.

BACKGROUND AND STUDY AIMS: There are no guidelines for the timing of conversion from a single-guidewire to a double-guidewire technique to facilitate selective bile duct cannulation and reduce post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), when using wire-guided cannulation. We investigated whether early conversion to the double-guidewire method, at first unintentional insertion of a guidewire into the pancreatic duct, facilitated selective bile duct cannulation and reduced PEP compared with repeated single-guidewire attempts. PATIENTS AND METHODS: A multicenter prospective randomized controlled trial included 274 patients with a naive papilla, undergoing endoscopic retrograde cholangiography (ERC) using wire-guided cannulation in whom there was unintentional insertion of the guidewire into the pancreatic duct. With the guidewire still in the duct, patients were randomly assigned to undergo the double-guidewire technique or repeated single-wire cannulation. Main outcomes were success rates for selective bile duct cannulation and PEP frequency. RESULTS: Success rates for selective bile duct cannulation within 10 attempts and 10 minutes were 75 % and 70 %, respectively, for the early double-guidewire (EDG) and repeated single-guidewire (RSG) cannulation groups (relative rate 1.07, 95 % confidence interval [95 %CI] 0.93 - 1.24, P = 0.42). Corresponding final selective bile duct cannulation rates were 98 % and 97 % (relative rate 1.01, 95 %CI 0.97 - 1.05, P = 1.00). PEP rates were 20 % and 17 %, respectively, for the EDG and RSG cannulation groups (relative risk 1.17, 95 %CI 0.71 - 1.94, P = 0.53). Double-guidewire cannulation was more effective in patients with malignant biliary stricture (relative rate 1.36, 95 %CI 1.05 - 1.77, P = 0.02). CONCLUSIONS: During therapeutic ERC using wire-guided cannulation, converting to a double-guidewire technique neither facilitated selective bile duct cannulation nor decreased PEP incidence compared with repeated use of a single-wire technique.

Clinical outcomes of secondary gastroduodenal self-expandable metallic stent placement by stent-in-stent technique for malignant gastric outlet obstruction.

BACKGROUND AND AIM: To evaluate the efficacy and safety of secondary gastroduodenal stent placement after first stent dysfunction for malignant gastric outlet obstruction. METHODS: We conducted a retrospective analysis to investigate the efficacy and safety of secondary stent-in-stent gastroduodenal stent placement. RESULTS: Among 260 patients who had been treated with first gastroduodenal stent placement for malignant gastric outlet obstruction, 29 patients (11.2%) were treated with secondary gastroduodenal stent placement because of first stent dysfunction. Pancreatic cancer was the major primary cancer (55.2%). A WallFlex duodenal stent was the most frequently inserted stent both as a first stent (75.9%) and as a secondary stent (62.1%). There were 22 patients (75.9%) that received gastroduodenal stents at the bending site (supraduodenal angle or infraduodenal angle). Technical and clinical success rates were 100% and 86.2%, respectively. Median eating period was 3.0 months, and median survival time was 3.5 months. As for related complications, gastrointestinal perforation, insufficient stent expansion, tumor ingrowth, tumor overgrowth, and cholangitis were experienced in 13.8% (four cases), 6.9% (two cases), 6.9% (two cases), 3.4% (one case), and 3.4% (one case), respectively. CONCLUSION: Secondary gastroduodenal stent placement might be effective for managing first stent dysfunction in malignant gastric outlet obstruction. However, gastrointestinal perforation was the major complication.

Transmural biliary drainage can be an alternative to transpapillary drainage in patients with an indwelling duodenal stent.

BACKGROUND: Self-expandable metal stents (SEMS) are widely utilized to relieve symptoms of malignant gastric outlet obstruction (GOO), but GOO is frequently complicated by nonresectable distal biliary obstruction. The optimal endoscopic approach to biliary drainage in this setting remains controversial and has yet to be resolved. AIMS: To compare the safety and efficacy of endoscopic ultrasound-guided transmural biliary drainage (EUS-BD) and transpapillary drainage in patients with an indwelling duodenal SEMS. METHODS: Patients who underwent EUS-BD or transpapillary drainage for distal malignant biliary obstruction with an indwelling duodenal SEMS between June 2007 and August 2012 at three Japanese tertiary referral centers were identified retrospectively. We compared times to stent dysfunction, causes of dysfunction, and procedural related complications between these two groups. RESULTS: Twenty patients were included in the study (7 EUS-BD and 13 transpapillary drainage). EUS-BD was performed via hepaticogastrostomy using a SEMS in three patients and via choledochoduodenostomy using a SEMS or a plastic stent in two patients each. Transpapillary drainage was performed using a SEMS in all patients. The stent patency rate in the EUS-BD group was higher than that in the transpapillary drainage group (100 vs. 71% at 1 month and 83 vs. 29% at 3 months, respectively). The rate of stent dysfunction in the EUS-BD group tended to be lower than that in the transpapillary group (14 vs. 54%; P = 0.157). Complication rates were similar between the groups (P = 1.000), with moderate bleeding in one patient in the EUS-BD group and mild pancreatitis in one patient in the transpapillary group. CONCLUSION: Endoscopic ultrasound-guided transmural biliary drainage is an alternative to transpapillary drainage in patients with an indwelling duodenal SEMS.

Risk factors for covered metallic stent migration in patients with distal malignant biliary obstruction due to pancreatic cancer.

BACKGROUND AND AIM: Covered metallic stents (CMSs) were developed to overcome tumor ingrowth in uncovered metallic stents (UMSs) for malignant biliary obstruction, but superiority of CMSs over UMSs is still controversial due to the high migration rate in CMS. Therefore, we conducted this retrospective analysis to clarify risk factors for stent migration, including mechanical properties of CMSs. METHODS: Patients with unresectable pancreatic cancer, receiving CMS for distal malignant biliary obstruction in five tertiary care centers, were retrospectively studied. Univariate and multivariate analyses to identify prognostic factors for early (< 6 months) stent migration were performed using a proportional hazards model with death or stent occlusion without stent migration as a competing risk. Two mechanical properties were included in the analysis: axial force, the recovery force that leads to a CMS straightening, and radial force (RF), the expansion force against the stricture. RESULTS: Among 290 patients who received CMS placement for distal malignant biliary obstruction, stent migration rate was 15.2%. CMS migrated early (< 6 months) in 10.0% and distally in 11.7%, respectively. In the multivariate analysis, significant risk factors for early stent migration were chemotherapy (subdistribution hazard ratios [SHR] 4.46, P = 0.01), CMS with low RF (SHR 2.23, P = 0.03), and duodenal invasion (SHR 2.25, P = 0.02). CONCLUSION: CMS with low RF, chemotherapy, and duodenal invasion were associated with CMS migration from our study.