TOKYO criteria 2014 for transpapillary biliary stenting

Comparison of the preoperative transpapillary unilateral biliary drainage methods for the future remnant liver in patients with hilar cholangiocarcinoma with liver resection: a retrospective cross-sectional study

BACKGROUND

Transpapillary preoperative biliary drainage (PBD) only for the future remnant liver (FRL) in hilar cholangiocarcinoma (HCCA) can be performed minimally invasively, with the expectation of swelling of the FRL. However, verification of the appropriate transpapillary unilateral PBD method for FRL is limited as the cases of liver resection are insufficient.

METHODS

A total of 63 patients with resectable HCCA were evaluated. Of note, 12 unilateral across-the-papilla plastic stent (PS) placement cases (PS group), 14 unilateral intraductal PS (IS) placement cases (IS group), and 11 unilateral endoscopic nasobiliary drainage cases (ENBD group) met the inclusion criteria. Each group was compared in terms of the hospital stay duration for the endoscopic procedure, recurrent biliary obstruction (RBO), time to RBO (TRBO), overall survival (OS), and surgical outcomes.

RESULTS

No significant differences were observed in the patient characteristics between the groups. Hospital stay for the endoscopic procedure was significantly longer in the ENBD group (50 days [IQR, 33-163]) than in the PS group (14 days [IQR, 2-36]; P <.01) or IS group (21 days [IQR, 6-118]; P <.01). There were no significant differences in the RBO, TRBO, OS, surgical time, amount of intraoperative blood loss, or postsurgical adverse events (AEs) between the groups. In the multivariate analysis, there were no significantly related factors for RBO, TRBO, OS, and postsurgical AEs.

CONCLUSION

The PS, IS, and ENBD groups showed similar clinical outcomes in liver resection cases for HCCA, excluding the hospital stay duration for the endoscopic procedure. Considering the hospital stay duration, unilateral PS and IS placement can be considered acceptable for transpapillary PBD.

Transpapillary biliary drainage using a forward-viewing endoscope for patients with distal malignant biliary obstruction and type I duodenal stenosis

Background and study aims

Distal malignant biliary obstruction and duodenal stenosis may be complicated in patients with pancreaticobiliary cancer. It is often difficult to insert a side-viewing duodenoscope and perform transpapillary biliary drainage in patients with duodenal stenosis on the oral side of the major papilla; hence, in this study, we attempted transpapillary biliary drainage using a forward-viewing endoscope and reported its efficacy and safety.

Patients and methods

This retrospective single-center cohort study included 12 patients (17 sessions) who underwent transpapillary biliary drainage using a forward-viewing endoscope between April 2020 and October 2024. The tip of the forward-viewing endoscope was inverted around the inferior duodenal angulus and the major papilla was viewed from the anal side. We evaluated patient characteristics, outcomes, and adverse events (AEs) during these procedures.

Results

Biliary cannulation and drainage were successful in all cases, with a median cannulation and procedure time of 7 minutes (range 0.5-34) and 33 minutes (range 10-101), respectively. Median biliary cannulation time required was 3.5 minutes (range 0.5-15) for 10 sessions in patients with a history of endoscopic sphincterotomy and 9 minutes (range 4-34) for seven sessions in patients with native papilla ( P = 0.01). The types of biliary drainage were plastic stent in nine sessions, endoscopic nasobiliary drainage in two sessions, and self-expandable metal stent in six sessions. Hyperamylasemia as AEs occurred in three sessions.

Conclusions

Transpapillary biliary drainage using a forward-viewing endoscope is a useful option for patients with type I duodenal stenosis.

Unilateral drainage and chemotherapy prolong the patency of a plastic stent placed above the sphincter of Oddi in patients with malignant hilar biliary obstruction

OBJECTIVES

To evaluate the results of inside stent therapy for unresectable malignant hilar biliary obstruction and identify factors related to stent patency duration.

METHODS

Of 44 patients who underwent initial inside-stent placement above the sphincter of Oddi from April 2017 to December 2022, 42 with the resolution of jaundice (clinical success rate, 95.5%) were retrospectively analyzed. Univariate and multivariate logistic regression analysis identified factors associated with stent patency duration.

RESULTS

Univariate analysis revealed significant differences in the drainage method (406 days for unilateral drainage vs. 305 days for bilateral drainage of the right and left liver lobes, p = 0.022) with or without chemotherapy (406 days with vs. 154 days without, p = 0.038). Multivariate analysis (Cox proportional hazards analysis) revealed similar results, with unilateral drainage (p = 0.031) and chemotherapy (p = 0.048) identified as independent factors associated with prolonged stent patency. Early adverse events were observed in two patients (4.8%; one cholangitis, one pancreatitis).

CONCLUSIONS

Inside-stent therapy was safely performed in patients with malignant hilar biliary obstruction. Simple unilateral drainage and chemotherapy may prolong stent patency.

Uncovered Self-Expandable Metallic Stent with an Ultra-Thin Delivery Sheath in Unresectable Malignant Hilar Biliary Obstruction: A Multicenter Prospective Observational Study

BACKGROUND

Although various self-expandable metallic stents (SEMSs) for malignant hilar biliary obstruction (MHBO) have been introduced, the optimal SEMS for MHBO has not yet been established.

PURPOSE

This study aimed to evaluate outcomes of the transpapillary placement of an uncovered laser-cut SEMS with an ultra-thin delivery sheath (YABUSAME) for MHBO.

METHODS

This multicenter, prospective study was conducted in 11 hospitals for 10 months (from March 2022 to December 2022). The primary outcome was the stent patency rate at 6 months. Key secondary outcomes were the technical success rate, clinical success rate, time to recurrent biliary obstruction (RBO), overall survival (OS), and adverse events.

RESULTS

Of 45 enrolled patients, 43 patients underwent biliary drainage, including 42 patients who underwent YABUSAME placement; 66.7% of patients received chemotherapy, and 60% had previously undergone biliary drainage. Drainage methods were partial stent-in-stent, side-by-side, and unilateral in 65.1%, 7.0%, and 27.9% of patients, respectively. Technical and clinical success rates were 93.2% (41/45) and 79.1% (34/45), respectively. The incidence rate of early postprocedural adverse events was 2.2%. The stent patency rate at 6 months was 55.3%. The median time to RBO was 231 days. The median OS was 125 days.

CONCLUSION

This study showed that the primary outcome, the 6-month stent patency rate, exceeded the expected rate of 55%, which indicates the efficacy of YABUSAME placement for MHBO.

Efficacy and safety of uncovered self-expandable metal stents for distal malignant biliary obstruction in unresectable non-pancreatic cancer

Objectives

The efficacy of uncovered self-expandable metal stents (UCSEMS) versus fully covered self-expandable metal stents for distal malignant biliary obstruction remains controversial. Additionally, the heterogeneity of the disease conditions has been indicated in previous studies because pancreatic and non-pancreatic cancers have different characteristics in clinical course. Therefore, the etiology of biliary obstruction necessitates investigations stratified by primary disease. This study aimed to evaluate the outcomes of UCSEMS, specifically for non-pancreatic cancer-induced distal malignant biliary obstruction.

Methods

We conducted a single-center retrospective review to evaluate the time to recurrent biliary obstruction and frequency of adverse events (AEs) in patients receiving UCSEMS for unresectable non-pancreatic cancer-induced malignant biliary obstruction.

Results

Overall, 32 patients were enrolled in the study between January 2016 and December 2023. The median time to recurrent biliary obstruction was 140 days. AE rates were low at 3.1% for both pancreatitis and cholecystitis, suggesting a potential benefit of UCSEMS in reducing post-procedural AEs.

Conclusion

UCSEMS may reduce the risk of post-procedural AEs and should be considered in patients at high risk of post-endoscopic retrograde cholangiopancreatography pancreatitis. However, the patency period may be shorter, necessitating future comparative research with fully covered self-expandable metal stents to determine the optimal stent choice.

The anti-migration effect of partially covered self-expandable metal stents for unresectable malignant distal biliary obstruction: A multicenter comparative study

Objectives

Covered self-expandable metal stents are commonly used for unresectable malignant distal biliary obstruction. Partially covered self-expandable metal stents have uncovered sections at both ends; however, their anti-migration effect remains unclear. The objective of this study was to evaluate that effect by comparing such stents with fully covered self-expandable metal stents for patients with unresectable malignant distal biliary obstruction.

Methods

This was a multicenter, retrospective comparative study of partially covered stents with fully covered stents for unresectable malignant distal biliary obstruction. Stent migration, recurrent biliary obstruction, and the time to recurrent biliary obstruction were compared between them.

Results

Thirty-nine patients with partially covered stents were included and compared with 42 patients with fully covered stents. The partially covered group had a significantly lower stent migration rate (3% vs. 36%; p < 0.001). The recurrent biliary obstruction rate was significantly lower in the partially covered group (21% vs. 43%; p = 0.036). The non-recurrent biliary obstruction rate at 6 months was 90% and 68% in the partially and fully covered groups, respectively. The time to recurrent biliary obstruction was significantly longer in the partially covered group (Gray's test, p = 0.016). Only partially covered stent placement was significantly associated with a lower risk of stent migration (subdistribution hazard ratio = 0.077; 95% confidence interval = 0.01-0.60; p = 0.014) in the multivariable analysis.

Conclusions

The anti-migration effect of partially covered self-expandable metal stents was associated with a reduced recurrence of biliary obstruction and prolonged time to such obstruction.

Efficacy and safety of a novel polytetrafluoroethylene-coated self-expandable metal stent for distal malignant biliary obstruction

Background

Stent migration and sludge formation remain significant problems associated with covered self-expandable metal stents (CSEMSs). The EGIS biliary stent fully covered flare type (EGIS biliary stent), a new type of polytetrafluoroethylene-coated self-expandable metal stent with low axial force and an anti-migration system, was developed to overcome these disadvantages. We conducted this study to evaluate the efficacy and safety of this stent in comparison with conventional CSEMS (c-CSEMS).

Methods

We retrospectively analyzed consecutive patients with unresectable pancreatic cancer who received initial CSEMS for distal malignant biliary obstruction. The primary outcome was time to recurrent biliary obstruction (RBO). Secondary outcomes included technical success rate, functional success rate, stent-related adverse events, causes of RBO, and re-intervention.

Results

A total of 40 patients were included (EGIS group: 20; c-CSEMS group: 20). The technical and functional success rates were similar between the two groups. Stent-related adverse event rates (20% vs. 15%, p > 0.99) and overall RBO rates (56% vs. 50%, p > 0.99) were not significantly different between the two groups. Stent migration was the most common cause of RBO in the EGIS group, while stent occlusion was in the c-CSEMS group. The median time to RBO (102 vs. 434 days, p = 0.10) was not significantly different between the two groups. Endoscopic transpapillary re-intervention was successful in most patients in both groups.

Conclusions

The EGIS biliary stent was not associated with a longer time to RBO compared to c-CSEMS. Further improvements, especially against stent migration, are needed to improve its efficacy.

Endoscopic ultrasound-guided choledochoduodenostomy versus hepaticogastrostomy combined with gastroenterostomy in malignant double obstruction (CABRIOLET_Pro): A prospective comparative study

OBJECTIVES

Malignant double obstruction, defined as the simultaneous presence of biliary and gastric outlet obstruction, represents a challenging clinical scenario. Previous retrospective experiences have demonstrated shorter dysfunction-free survival (DyFS) of endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) versus EUS-hepaticogastrostomy (EUS-HGS) in this setting, but no prospective evidence is available.

METHODS

Twenty consecutive patients with malignant double obstruction, treated with EUS-gastroenterostomy (and EUS-guided biliary drainage, following a previously failed ERCP, were enrolled in a prospective observational study (ClinicalTrials.gov NCT04813055) comparing EUS-CDS versus EUS-HGS. Efficacy and safety were evaluated, with Biliary Dysfunctions as the primary outcome and DyFS using Kaplan-Meier estimates as a primary measure.

RESULTS

Twenty patients (75% with pancreatic cancer, 50% with metastatic disease) with EUS-gastroenterostomy were included (seven EUS-CDS and 13 EUS-HGS). No significant difference was detected at baseline. Technical success was 100% in both groups. EUS-CDS compared to EUS-HGS showed similar clinical success (100% vs. 92.3%, p = 0.5), a higher rate of post-procedural adverse events (42.9% vs. 7.7%, p = 0.067, mostly related to severe/fatal cholangitis in the EUS-CDS group) and a higher rate of biliary dysfunctions during follow-up (71.4% vs. 16.7%, p = 0.002).DyFS was significantly shorter in the EUS-CDS group (39 [15-62] vs. 268 [192-344] days, p = 0.0023), with a 30-days DyFS probability of 57.1% vs. 100% (hazard ratio = 7.8 [1.4-44.2]).

CONCLUSIONS

In this prospective comparison of patients with malignant double obstruction undergoing EUS-gastroenterostomy, treating jaundice with EUS-CDS versus EUS-HGS resulted in a reduced probability of survival without biliary events and an increased risk of biliary dysfunctions (number needed to harm = 1.8), with detection of severe/fatal cholangitis.

Re-intervention Utility After Endoscopic Ultrasound-Guided Hepaticogastrostomy Using a Partially Covered Stent with Anchoring Flange

BACKGROUND AND AIM

Although long self-expandable metal stent (SEMS) with a sufficient intragastric portion is typically preferred for endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS), this design can complicate endoscopic re-intervention for recurrent biliary obstruction (RBO). We evaluated the efficacy and safety of endoscopic re-intervention for RBO through the stent after EUS-HGS using a novel partially covered SEMS with an anchoring flange.

METHODS

The partially covered SEMS was designed with a intrahepatic uncovered portion measuring 1.5 cm in length and a resilient fold-back wide distal anchoring flange with a 2.0 cm diameter. Re-interventions were performed through the stent lumen while the stent was in situ. The primary outcomes were technical and clinical success, and secondary outcomes were procedure time, adverse events, and the median time to RBO after re-intervention.

RESULTS

In total, 35 re-interventions were performed in 19 patients. Re-intervention was successfully conducted in 97.1% (34/35) of cases via the intragastric end of the stent in a retroflexed position. Technical and clinical success were 94.3% (33/35) and 88.6% (31/35). Re-intervention methods included stent cleaning (18.2%), additional HGS stent placement (33.3%), and antegrade stent placement (48.5%). Mild cholangitis occurred in 5.7% (2/35) of patients and was managed conservatively. The median time to RBO after re-intervention was 148 days.

CONCLUSION

Endoscopic re-interventions can be effectively and safely performed through the lumen of the novel partially covered SEMS with an anchoring flange.

6-mm vs 10-mm diameter fully covered self-expandable metal stents in patients with unresectable malignant distal bile duct stricture (COSMIC UNISON): study protocol for a multicenter, randomized controlled trial

BACKGROUND

Unresectable malignant bile duct stricture (often caused by unresectable pancreatic cancer and cholangiocarcinoma) can be drained via insertion of self-expandable metal stents (SEMS) during endoscopic retrograde cholangiopancreatography (ERCP). Because recurrent biliary obstruction (RBO) and complications following stent insertion can delay chemotherapy and other treatments, a longer time to RBO (TRBO) is desirable. Although a longer TRBO has been reported among patients who undergo insertion with larger diameter SEMS, patients who undergo insertion with smaller diameter fully covered SEMS (FCSEMS) may have a lower incidence of complications than those with larger diameter FCSEMS. The aim of this study is to determine the TRBO and incidence of complications with 6-mm FCSEMS vs 10-mm FCSEMS in patients with unresectable malignant distal bile duct stricture.

METHODS

In this multicenter, open-label, randomized controlled, non-inferiority trial (COSMIC UNISON), a target of 250 patients over 23 locations in Japan will receive either the 6-mm FCSEM or the standard 10-mm FCSEM during ERCP, with 125 patients in each group. The observation period will be 24 months, and patients will be enrolled from 15 March 2024 and assessed until the date of RBO or the study end (31 March 2029). The primary endpoint is TRBO, with RBO defined as the coexistence of abnormal liver enzyme values and dilation of the common bile duct and intrahepatic bile duct upstream of the stent. The secondary endpoints are the incidence and rates (at 3, 6, and 12 months) of non-RBO events, overall survival, cause of RBO, and symptomatic stent deviation. Adverse events from endoscopic procedures will be classified by the Lexicon Classification from the American Society of Endoscopy, and all other adverse events will be classified per the Japanese translation of the Common Terminology Criteria for Adverse Events version 5.0.

DISCUSSION

The COSMIC UNISON study is anticipated to provide evidence regarding the efficacy and safety of 6-mm vs 10-mm FCSEMS to inform the use of 6-mm FCSEMS for the treatment of unresectable malignant distal bile duct stricture.

TRIAL REGISTRATION

Japan Registry of Clinical Trials identifier: jRCT1042230170. Prospectively registered on 15 March 2024.

Incidence of Cholecystitis After Endoscopic Biliary Drainage Using a Low Axial Force Covered Self-Expandable Metallic Stent in Patients With Malignant Distal Biliary Obstruction: A Multicenter Prospective Study

BACKGROUND AND AIM

No prospective studies have verified the incidence of cholecystitis in patients using the covered self-expandable metallic stent. In this study, we aimed to investigate the incidence of cholecystitis and its risk factors after low axial force covered self-expandable metallic stent placement for malignant distal biliary obstruction.

METHODS

This multicenter prospective study included patients diagnosed with unresectable distal biliary obstruction between November 2019 and October 2022 who underwent low axial force covered self-expandable metallic stent placement.

RESULTS

The technical success in the 93 analyzed patients was 100% and clinical success was 98.9%. The 70-mm covered self-expandable metallic stent was the most used in 53 patients (57.0%), followed by the 80-mm type in 27 patients (29.0%), 60-mm type in 12 patients (12.9%), and 50-mm type in 1 patient (1.1%). Cholecystitis after covered self-expandable metallic stent placement occurred in six patients (6.5%). The median time to onset was 46 days (range, 16-315 days), with 1 case in the early stage and five cases in the late stage. There was one mild case, one moderate case, and four severe cases. The presence of tumor involvement at the orifice of the cystic duct was identified as an independent risk factor (odds ratio, 17.0; 95% confidence interval, 1.5-195.1; p = 0.023).

CONCLUSIONS

The presence of tumor involvement at the orifice of the cystic duct was an independent risk factor for the development of cholecystitis after low axial covered self-expandable metallic stent placement.

TRIAL REGISTRATION

University Hospital Medical Information Network (UMIN) (http://www.umin.ac.jp, registration number: UMIN 000038209).

Assessment of safety and patency of 7-mm covered metal stents for preoperative biliary drainage in pancreatic cancer: Prospective multicenter study

Background and study aims

For preoperative biliary drainage of pancreatic cancer (PC), a 10-mm diameter metal stent (MS) is commonly used; however, the rate of pancreatitis is high. It is hypothesized that smaller-diameter MS may reduce the rate of pancreatitis. Therefore, we conducted a multicenter prospective study to evaluate the efficacy and safety of 7-mm MS.

Patients and methods

Patients requiring initial biliary drainage for obstructive jaundice caused by PC and scheduled for surgery from six facilities were included. After endoscopic retrograde cholangiography, a 7-mm MS was placed at the site of biliary obstruction. The primary endpoint was the rate of pancreatitis, and the secondary endpoints included early and late adverse events (AEs). The pancreatitis rate was assumed to be 18% and 5% with 10- and 7-mm MS, respectively; with a power of 80% and one-sided significance level of 10%, the planned enrollment was 38 patients. If pancreatitis occurred in no more than three patients, this indicates that the 7-mm MS effectively reduced incidence of pancreatitis.

Results

Overall, 38 patients were enrolled, and 35 patients in whom a 7-mm MS was successfully placed were analyzed. All MS were placed after sphincterotomy. Pancreatitis occurred in four patients (11.4%) and no early AEs were observed. Surgery was performed in 24 patients and late AEs included stent occlusion in eight patients (23%) and cholecystitis in four patients (11%).

Conclusions

The 7-mm MS did not reduce incidence of pancreatitis among surgical candidates for PC.

Metal stent versus plastic stent in endoscopic ultrasound-guided hepaticogastrostomy for unresectable malignant biliary obstruction: Large single-center retrospective comparative study

OBJECTIVE

Whether metal stents (MS) or plastic stents (PS) yield better outcomes for malignant biliary obstruction in endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is controversial. We aimed to compare outcomes of initial EUS-HGS performed with MS or PS.

METHODS

In this single-center retrospective study, we included patients (MS/PS groups: n = 151/72) with unresectable malignant biliary obstruction and performed multivariable analysis. The landmark date was defined as day 100 and used to evaluate the time to recurrent biliary obstruction (TRBO).

RESULTS

The clinical success rate was similar in both groups. The mean total bilirubin percentage decrease at week 2 was significantly higher in the MS group than in the PS group (-45.1% vs. -23.7%, P = 0.016). Median TRBO was significantly different between the MS and PS groups (183 and 92 days, respectively; P = 0.017). TRBO within 100 days was comparable in both groups but was significantly shorter only after 100 days in the PS group (adjusted hazard ratio 12.8, P < 0.001). Adverse events were significantly more common in the MS group (23.8% vs. 9.7%, P = 0.012), although they occurred relatively frequently even with PS in the cholangitis subgroup (Pinteraction = 0.034). After endoscopic re-intervention, TRBO tended to be longer with revision PS (hazard ratio 0.40, P = 0.47).

CONCLUSIONS

Although MS provided early improvement of jaundice and long stent patency, PS provided a better safety profile and comparable stent patency until 100 days. PS might also be an adequate and optimal palliation method in EUS-HGS.

Endoscopic ultrasound-guided hepaticogastrostomy and endoscopic retrograde cholangiopancreatography-guided biliary drainage for distal malignant biliary obstruction due to pancreatic cancer with asymptomatic duodenal invasion: a retrospective, single-center study in Japan

BACKGROUND/AIMS

Duodenal invasion (DI) is a risk factor for early recurrent biliary obstruction (RBO) in endoscopic retrograde cholangiopancreatography-guided biliary drainage (ERCP-BD). Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) may reduce early RBO in cases of asymptomatic DI, even when ERCP is possible.

METHODS

We enrolled 56 patients with pancreatic cancer and asymptomatic DI who underwent EUS-HGS (n=25) or ERCP-BD (n=31). Technical and clinical success, early (<3 months) and overall RBO rates, time to RBO (TRBO), and adverse events were compared between the EUS-HGS and ERCP-BD groups. Risk factors for early RBO were also evaluated.

RESULTS

Baseline characteristics were similar between the groups. Both procedures demonstrated 100% technical and clinical success rates, with a similar incidence of adverse events (48% vs. 39%, p=0.59). While the median TRBO was comparable (5.7 vs. 8.8 months, p=0.60), EUS-HGS was associated with a lower incidence of early RBO compared to ERCP-BD (8% vs. 29%, p=0.09). The major causes of early RBO in ERCP-BD were sludge and food impaction, rarely occurring in EUS-HGS. EUS-HGS was potentially reduced early RBO (odds ratio, 0.32; p=0.07).

CONCLUSIONS

EUS-HGS can be a viable option for treating pancreatic cancer with asymptomatic DI.

Potential of 6-mm-diameter fully covered self-expandable metal stents for unresectable malignant distal biliary obstruction: a propensity score-matched study

BACKGROUND/AIMS

To date, only thinner-diameter metal stents have been evaluated for unresectable malignant distal biliary obstruction (UR-MDBO). This study investigated the outcomes and optimal cohorts for a 6-mm-diameter fully covered self-expandable metal stent (FCSEMS) compared with those for a 10-mm-diameter FCSEMS.

METHODS

This single-center retrospective cohort study included patients who underwent initial transpapillary metal stenting for UR-MDBO. Propensity score matching (1:1) analysis was performed.

RESULTS

Of 133/68 patients who underwent 6-mm/10-mm-diameter FCSEMS deployment, 59 in each group were selected. The median time to recurrent biliary obstruction was not significantly different between the groups (p=0.46). In contrast, use of the 6-mm-diameter FCSEMS resulted in a significantly reduced incidence of stent-related adverse events (AEs) (p=0.016), especially cholecystitis (p=0.032), and patients aged <70 years were particularly affected by this significant reduction. Among the patients in the end-stage cohort who were unable to continue chemotherapy after FCSEMS deployment, the free rate of stent-related events, including recurrent biliary obstruction and stent-related AEs, was significantly higher in the 6-mm group (p=0.027).

CONCLUSIONS

For UR-MDBO, a 6-mm-diameter FCSEMS can be an optimal and safe option in the younger cohort with a relatively high risk of AEs and in the end-stage cohort requiring safer drainage without interference from stent-related events during times of poor prognosis.

Efficacy and safety of a fully covered self-expandable metallic stent equipped with square flare in EUS-guided drainage/anastomosis: A multicenter retrospective study

Background and Objectives

Recent technological advances in interventional EUS have improved EUS-guided drainage/anastomosis (EUS-D/A), yet challenges remain. This study evaluated the safety and feasibility of a square flare fully covered self-expandable metallic stent (SF-FCSEMS) with anti-migration properties for EUS-D/A.

Methods

This retrospective cohort study was performed at 2 academic centers and analyzed patients who underwent SF-FCSEMS placement for EUS-D/A from April 2015 to November 2022. We have used an SF-FCSEMS that has a square flare at both ends that is 4 mm larger in diameter than the stent body, providing an anti-migration effect.

Results

Thirty-six patients (median age: 74 years), 41.6% male, were included. Malignancies accounted for 83.3%. Among the EUS-D/A procedure types, EUS-abscess drainage was performed in 52.8%, EUS-guided gallbladder drainage in 30.6%, and EUS-guided abscess drainage in 16.7%. The technical success rate was 97.2%, and the clinical success rate was 97.1%. The median procedure time was 36 minutes, with puncture tract dilation conducted in all cases. Adverse events occurred in 11.1%; recurrent symptoms were observed in 11.8%, with no migration. SF-FCSEMS removal was performed in 26.5% of patients during the follow-up period, with a median duration of 154 days. The total cost of deploying SF-FCSEMS was approximately 40% less than that of using lumen apposing metal stent.

Conclusions

EUS-D/A with an SF-FCSEMS, which has anti-migration properties, not only was effective and feasible in the present study but also demonstrated a cost advantage.

Feasibility of Endoscopic Ultrasound-Guided Hepaticogastrostomy for Malignant Hilar Biliary Obstruction

BACKGROUND

Almost all previous reports on endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) involve malignant distal bile duct strictures. However, the feasibility of EUS-HGS for malignant hilar biliary obstruction (MHBO) remains unclear.

AIMS

This study aimed to evaluate the efficacy and safety of EUS-HGS for MHBO and identify the risk factors associated with technical failure.

METHODS

In this multicenter retrospective study, we reviewed consecutive patients who underwent EUS-HGS between April 2017 and March 2023 at five institutions. We assessed the overall feasibility and efficacy of EUS-HGS for MHBO, including the factors associated with technical failure, using multivariable logistic regression analysis.

RESULTS

A total of 85 patients were enrolled (mean age, 72 years; 36.4% female). Thirty-six patients (42.3%) had surgically altered anatomy, and 43 (50.6%) underwent biliary stenting by transpapillary or percutaneous biliary drainage before EUS-HGS. The rates of technical success, clinical success, and adverse events were 87.0% (74/85), 76.4% (65/85), and 11.8% (10/85), respectively. Multivariable analysis demonstrated that a bile duct diameter ≤ 4 mm was the only independent risk factor for technical failure (odds ratio, 6.12; 95% confidence interval, 1.02-36.6; P = 0.047). The most common reason for technical failure was cholangiography failure (45.4%), followed by inappropriate guidewire position (36.4%).

CONCLUSIONS

EUS-HGS is a challenging but promising treatment option for MHBO. Patients with a bile duct diameter ≤ 4 mm or inappropriate guidewire position should be careful as these factors can lead to the technical failure of EUS-HGS for MHBO.

Correlation between liver volume drainage and clinical success after endoscopic biliary drainage of hilar malignant obstruction

BACKGROUND AND AIM

Malignant hilar obstruction usually presents in advanced-stage disease with a poor prognosis. Effective biliary drainage is essential for the beginning of palliative chemotherapy. There is a debate on the amount of liver parenchyma that should be drained to achieve clinical success. This study aimed to correlate the volume of liver drained with clinical success rate.

METHODS

The authors conducted a retrospective study including patients with malignant hilar biliary obstruction who underwent retrograde endoscopic cholangiography for biliary drainage from January 2014 to December 2018. The main outcome was a correlation of clinical success rate with hepatic volume drained. Secondary outcomes were correlation of clinical success rate with the quantity of liver sectors drained and unilateral versus bilateral drainage.

RESULTS

82 patients met inclusion criteria (58.5 % female), with a mean age of 60±13 years. The main cause of hilar obstruction was cholangiocarcinoma (32.9 %) followed by lymph node metastasis (23.2 %). Technical success was achieved in 75 patients (91.5 %), and clinical success in 45 patients (60 %). The authors found a significant correlation between clinical success rate when at least 50 % of viable parenchyma was drained (p = 0.016; OR = 4.15, 95 % CI 1.4-12.5). Considering liver sectors, higher clinical success rates were found when at least 2 sectors were drained (p < 0.001; OR = 8.50, 95 % CI 2.7-26.7). The correlation between unilateral versus bilateral drainage and clinical success was not statistically significant.

CONCLUSION

Drainage of at least 50 % of volume hepatic parenchyma was associated with better outcomes as well as drainage of at least 2 hepatic sectors, regardless of if unilateral or bilateral.

Hepatobiliary scintigraphy of bile excretion after endoscopic ultrasound-guided hepaticogastrostomy for malignant biliary obstruction: a retrospective study in Japan

BACKGROUND/AIMS

Hepatobiliary scintigraphy (HBS) is used to evaluate bile excretion. This study aimed to evaluate biliary excretion during endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) using HBS.

METHODS

We retrospectively evaluated 78 consecutive patients with malignant extrahepatic biliary obstruction, who underwent HBS after EUS-HGS between April 2015 and July 2022. The peak time and decay rate were scored with 0, 1, or 2 points based on thresholds of 20 and 35 minutes, and 10% and 50%, respectively. A total score of 4 or 3 was considered indicative of good bile excretion, whereas scores of 2, 1, or 0 indicated poor bile excretion.

RESULTS

The good and poor bile excretion groups included 40 and 38 cases, respectively. The group with good bile excretion had a significantly longer time to recurrent biliary obstruction compared to the poor bile excretion group (not reached vs. 124 days, p=0.026). Multivariate analysis identified the site of obstruction as a significant factor influencing good bile excretion (odds ratio, 3.39; 95% confidence interval, 1.01-11.4, p=0.049), with superior bile excretion observed in cases involving upper biliary obstruction compared to middle or lower biliary obstruction.

CONCLUSIONS

In patients with malignant biliary obstruction who underwent HGS, the site of obstruction is significantly associated with stent patency.

Trisectoral Metal Stenting Using Combined Stent-by-Stent and Stent-in-Stent Method for Malignant Hilar Biliary Obstruction: A Prospective Pilot Study

BACKGROUND

Endoscopic trisectoral metal stent (MS) placement for malignant hilar biliary obstruction (MHBO) poses technical challenges, although it may prolong survival and stent patency. Combined stent-by-stent and stent-in-stent (SBSIS) methods can reduce technical difficulty. This study aimed to examine the use of the SBSIS in patients with Bismuth type III or IV MHBO.

METHODS

This prospective pilot study enrolled 30 eligible patients between January 2020 and October 2022. The study outcomes included technical and clinical success, recurrent biliary obstruction (RBO), and adverse events (AE) besides RBO associated with SBSIS for MHBO.

RESULTS

The technical success rate was 93.3% (28/30 patients). Clinical success was achieved in all patients with technical success. The early and late AEs rates were 6.7% (2/30) and 7.1% (2/28), respectively. The incidence of RBO was 35.7% (10/28). RBO was treated with an endoscopic transpapillary approach in eight patients and an endoscopic ultrasound-guided transmural approach in two patients. The median time to RBO was 162 days, and the median overall survival was 148 days.

CONCLUSIONS

This first prospective study investigating the SBSIS method demonstrated good technical feasibility with a low AE rate. Therefore, it can be considered a better option when contemplating trisectoral MS placement for high-grade MHBO.

TOKYO criteria 2024 for the assessment of clinical outcomes of endoscopic biliary drainage

The consensus-based TOKYO criteria were proposed as a standardized reporting system for endoscopic transpapillary biliary drainage. The primary objective was to address issues arising from the inconsistent reporting of stent outcomes across studies, which has complicated the comparability and interpretation of study results. However, the original TOKYO criteria were not readily applicable to recent modalities of endoscopic biliary drainage such as biliary drainage based on endoscopic ultrasound or device-assisted endoscopy. There are increasing opportunities for managing hilar biliary obstruction and benign biliary strictures through endoscopic drainage. Biliary ablation has been introduced to manage benign and malignant biliary strictures. In addition, the prolonged survival times of cancer patients have increased the importance of evaluating overall outcomes during the period requiring endoscopic biliary drainage rather than solely focusing on the patency of the initial stent. Recognizing these unmet needs, a committee has been established within the Japan Gastroenterological Endoscopy Society to revise the TOKYO criteria for current clinical practice. The revised criteria propose not only common reporting items for endoscopic biliary drainage overall, but also items specific to various conditions and interventions. The term "stent-demanding time" has been defined to encompass the entire duration of endoscopic biliary drainage, during which the overall stent-related outcomes are evaluated. The revised TOKYO criteria 2024 are expected to facilitate the design and reporting of clinical studies, providing a goal-oriented approach to the evaluation of endoscopic biliary drainage.

Endoscopic treatment of bile duct stones with benign choledochojejunal anastomotic stenosis

BACKGROUND AND AIMS

Endoscopic interventions for bile duct stones (BDSs) with benign choledochojejunal anastomotic stenosis (bCJS) are challenging. Therefore, we investigated endoscopic interventions for BDSs with bCJS.

METHODS

Seventeen patients with BDSs with bCJS were retrospectively analyzed. Patient characteristics, technical success, adverse events (AEs), and recurrence were evaluated.

RESULTS

In 17 patients, the median diameters of the bile duct and BDSs were both 8 mm. The median number of BDSs was 3. The technical success rate was 94% (16/17). Ten patients underwent balloon dilation at the choledochojejunal anastomotic site (CAS), the median diameter of balloon dilation was 10.5 mm, and waist disappearance was achieved in 2. Six patients had fully covered self-expandable metal stents (FCSEMSs) with a diameter of 10 mm placed at the CAS. BDSs were removed after balloon dilation or FCSEMS removal, and 6 of 16 patients were treated with a combination of lithotripsy and 5 with peroral direct cholangioscopy (PDCS). Regarding AEs, perforation at the CAS by balloon dilation occurred in 1 patient. The median follow-up was 3701 days. Nine of 16 patients (56%) had recurrence. The patients treated with a combination of PDCS at BDS removal (P = .022) and waist disappearance at the CAS by balloon dilation (P = .035) had significantly fewer recurrences.

CONCLUSIONS

Endoscopic interventions for BDSs with bCJS are useful and relatively safe; however, long-term follow-up showed frequent recurrences. Recurrence was common in patients not treated with the combination of PDCS at BDS removal and those without waist disappearance at the CAS by balloon dilation.

Thin Delivery Stents Can Obviate the Need for Additional Fistula Dilatation of Large Diameter in Endoscopic Ultrasound-Guided Hepaticogastrostomy

Background/Objectives: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) often requires fistula dilation owing to the placement of a large diameter of the delivery stent. The recently developed delivery devices, which are as thin as 5.9/6.0 Fr, may save the need for fistula dilation. Therefore, we investigated whether large fistula dilation would be required or not in the case of this newly developed thin-diameter delivery stents. Methods: We conducted a retrospective study involving 33 patients implemented with a self-expandable metal stent (SEMS) during EUS-HGS. The patients were categorized based on the delivery device diameter into thin (n = 13; delivery device diameter: 5.9/6.0 Fr) and thick (n = 20; delivery device diameter: 8.5 Fr) groups. We compared the initial rate of success, technical success, and clinical success between the thin and thick groups. The initial rate of success was defined as successful stent placement without a balloon or large diameter mechanical dilation. Results: The rate of the initial stenting success was significantly higher in the thin group (100% [13/13]) compared with that in the thick group (65.0% [13/20]) (p = 0.027). In the thick group, seven cases with technical difficulty in terms of stent placement could be successfully completed with additional fistula dilation with a 9 Fr bougie dilator or 4 mm balloon dilator; this resulted in a technical success of 100% in both groups ultimately. The rate of clinical success was 100% and 95.0% in the thin and thick groups, respectively (p = 1.00). Conclusions: Thin delivery stents may facilitate stent placement without the need for a balloon fistula or large-diameter mechanical dilation.

Risk factors for recurrent biliary obstruction following suprapapillary placement of a plastic stent as preoperative biliary drainage for perihilar biliary malignancy

BACKGROUND/PURPOSE

The usefulness of endoscopic biliary stenting by deploying a plastic stent suprapapillary, called inside-stent (IS) placement, as preoperative biliary drainage (PBD) for perihilar biliary malignancy (PHBM) has been demonstrated. This study investigated risk factors for recurrent biliary obstruction (RBO) after IS placement.

METHODS

Consecutive patients with potentially resectable PHBM treated with IS placement as PBD between 2017 and 2023 at Nagoya University Hospital were retrospectively reviewed.

RESULTS

A total of 157 patients were included, with RBO occurring in 34 (22%) patients. The non-RBO rates were 83% at 30 days, 77% at 60 days, and 57% at 90 days. The most common cause of RBO was stent occlusion (n = 14), followed by segmental cholangitis (n = 12) and stent migration (n = 8). Stent migration and occlusion occurred more frequently within and after 1 week post-stenting, respectively. In multivariate analysis, biliary infection before IS was the sole risk factor for RBO, with a hazard ratio of 2.404 (95% confidence interval 1.163-4.972; p = .018). This risk was reduced by temporary endoscopic nasobiliary drainage prior to definitive IS placement.

CONCLUSIONS

Biliary infection before IS was identified as an independent risk factor for RBO in patients with PHBM with IS as PBD.

CLINICAL TRIAL REGISTER

Clinical trial registration number: UMIN000025631.

Evaluating optimal bilateral biliary stenting in endoscopic reintervention after initial plastic stent dysfunction for unresectable malignant hilar biliary obstruction: Retrospective cross-sectional study

OBJECTIVES

The placement of plastic stents (PS), including intraductal PS (IS), is useful in patients with unresectable malignant hilar biliary obstruction (UMHBO) because of patency and ease of endoscopic reintervention (ERI). However, the optimal stent replacement method for PS remains unclear.

METHODS

This retrospective study included 322 patients with UMHBO. Among them, 146 received PS placement as initial drainage (across-the-papilla PS [aPS], 54; IS, 92), whereas 75 required ERI. Eight bilateral aPS, 21 bilateral IS, and 17 bilateral self-expandable metallic stent (SEMS) placements met the inclusion criteria. Rates of technical and clinical success, adverse events, recurrent biliary obstruction (RBO), time to RBO (TRBO), overall survival, and secondary ERI were compared.

RESULTS

There were no significant intergroup differences in rates of technical or clinical success, adverse events, RBO occurrence, or overall survival. The median TRBO was significantly shorter in the aPS group (47 days) than IS (91 days; P = 0.0196) and SEMS (143 days; P < 0.01) groups. Median TRBO did not differ significantly between the IS and SEMS groups (P = 0.44). On Cox multivariate analysis, the aPS group had the shortest stent patency (hazard ratio 2.67 [95% confidence interval 1.05-6.76], P = 0.038). For secondary ERI, the median endoscopic procedure time was significantly shorter in the IS (22 min) vs. SEMS (40 min) group (P = 0.034).

CONCLUSIONS

Bilateral IS and SEMS placement featured prolonged patency after first ERI. Because bilateral IS placement is faster than SEMS placement and IS can be removed during secondary ERI, it may be a good option for first ERI.

Benefits of endoscopic gallbladder stenting following percutaneous transhepatic gallbladder drainage

BACKGROUND

Endoscopic transpapillary gallbladder drainage is challenging because of the complexity of the procedure and high incidence of adverse events (AEs). To overcome these problems, endoscopic gallbladder stenting (EGBS) after percutaneous transhepatic gallbladder drainage (PTGBD) can be effective, as it mitigates inflammation and adhesion.

AIM

To examine the benefits of EGBS after PTGBD to assess its efficacy and impact on AEs.

METHODS

We retrospectively analyzed data from 35 patients who underwent EGBS after PTGBD at a single center between January 2016 and December 2023. The primary outcomes were technical success and AEs, and the rate of recurrent cholecystitis was evaluated. In addition, the reasons for the failure of the procedure were identified.

RESULTS

Among the 35 patients, the technical success rate was 77.1% and the final contrast of the cystic duct was successful in 97.1% of patients. The incidence of early AEs was relatively low (11.4%), with no instances of cystic duct perforation. The rate of recurrent cholecystitis was 3.7%, and no other biliary events were observed.

CONCLUSION

EGBS after PTGBD may be significantly beneficial, with a substantial success rate and minimal AEs in both short- and long-term follow-ups.

Puncture angle on an endoscopic ultrasound image is independently associated with unsuccessful guidewire manipulation of endoscopic ultrasound-guided hepaticogastrostomy: a retrospective study in Japan

BACKGROUND/AIMS

Although endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is performed globally, the procedure remains challenging. Guidewire manipulation is the most difficult step, and there are few reports on the factors associated with unsuccessful guidewire manipulation. This study aimed to assess the significance of the puncture angle on EUS images and identify the most effective guidewire rescue method for patients with unsuccessful guidewire manipulation.

METHODS

We retrospectively enrolled 115 patients who underwent EUS-HGS between May 2016 and April 2022 at two centers. The puncture angle between the needle and the intrahepatic bile duct was measured through EUS movie records.

RESULTS

Guidewire manipulation was unsuccessful in 28 patients. Receiver operating characteristic (ROC) curves identified an optimal puncture angle cutoff value of 85° (cutoff value, 85°; area under the ROC curve, 0.826; sensitivity, 85.7%; specificity, 81.6%). Multivariate analysis demonstrated that a puncture angle <85° was a significant risk factor for unsuccessful guidewire manipulation (odds ratio, 19.8; 95% confidence interval, 6.42-61.5; p<0.001). Among the 28 unsuccessful cases, 24 patients (85.7%) achieved successful guidewire manipulation using various rescue methods.

CONCLUSIONS

The puncture angle observed on EUS is crucial for guidewire manipulation. A puncture angle of <85° was associated with unsuccessful guidewire manipulation.

EUS-guided hepaticogastrostomy versus EUS-guided hepaticogastrostomy with antegrade stent placement in patients with unresectable malignant distal biliary obstruction: a propensity score-matched case-control study

BACKGROUND AND AIMS

EUS-guided hepaticogastrostomy (EUS-HGS) is a rescue procedure when ERCP fails. Peritonitis and recurrent biliary obstruction (RBO) are adverse events (AEs) associated with EUS-HGS. Antegrade stent placement across a malignant distal biliary obstruction (DBO) followed by EUS-HGS (EUS-HGAS) creates 2 biliary drainage routes, potentially reducing peritonitis and prolonging time to RBO (TRBO). We compared the outcomes of the 2 techniques.

METHODS

Data of consecutive patients with malignant DBO who underwent attempted EUS-HGS or EUS-HGAS across 5 institutions from January 2014 to December 2020 were retrospectively analyzed. A matched cohort of patients was obtained using 1-to-1 propensity score matching. The primary outcome was TRBO, and secondary outcomes were AEs except for RBO and overall survival.

RESULTS

Among 360 patients, 283 (176 and 107 in the HGS and HGAS groups, respectively) were eligible. The matched cohorts included 81 patients in each group. AEs developed in 10 (12.3%) and 15 (18.5%) patients (P = .38) in the HGS and HGAS groups, respectively. RBO occurred in 18 and 2 patients in the HGS and HGAS groups, respectively (P < .001). TRBO was significantly longer in the HGAS group (median, 194 days vs 716 days; hazard ratio, .050; 95% confidence interval, .0066-.37; P < .01). However, no significant differences occurred in overall survival between the groups (median, 97 days vs 112 days; hazard ratio, .97; 95% confidence interval, .66-1.4; P = .88).

CONCLUSIONS

EUS-HGAS extended TRBO compared with EUS-HGS, whereas AEs, except for RBO and overall survival, did not differ. The longer TRBO of EUS-HGAS could benefit patients with longer life expectancy.

Comparison of stent patency between EUS-guided hepaticogastrostomy with bridging and endoscopic transpapillary biliary drainage for hilar obstruction

Background and study aims Endoscopic ultrasound-guided hepaticogastrostomy with bridging between the left and right bile ducts is an alternative to endoscopic transpapillary drainage for malignant hilar biliary obstruction. We aimed to analyze the long-term stent patency of endoscopic ultrasound-guided hepaticogastrostomy with bridging. Patients and methods Patients who underwent endoscopic ultrasound-guided hepaticogastrostomy with bridging between April 2018 and July 2023 were retrospectively analyzed. We retrospectively compared the stent patency of these patients with that of the individuals who underwent endoscopic transpapillary drainage-multi-stenting using unmatched (entire) and propensity score-matched cohorts. Results Endoscopic ultrasound-guided hepaticogastrostomy with bridging had a technical success rate of 90% (18/20). Adverse events were minimal. The number of clinical success cases was 17 and 82 for endoscopic ultrasound-guided hepaticogastrostomy with bridging using metallic stent and endoscopic transpapillary drainage-multi-stenting, respectively. The recurrent biliary obstruction rate was 17.6% and 58.5% for endoscopic ultrasound-guided hepaticogastrostomy with bridging and endoscopic transpapillary drainage-multi-stenting, respectively; the median time to recurrent biliary obstruction (days) was significantly longer for endoscopic ultrasound-guided hepaticogastrostomy with bridging in the entire (not reached vs. 104, P =0.03) and propensity score-matched (183 vs. 79, P =0.05) cohorts. The non-recurrent biliary obstruction rate for endoscopic ultrasound-guided hepaticogastrostomy with bridging was 91.6% at 3 and 6 months and 57% at 12 months. Multivariate analyses revealed that endoscopic ultrasound-guided hepaticogastrostomy with bridging contributed to a lower recurrent biliary obstruction incidence (hazard ratio, 0.31, P =0.05) without significant difference. Conclusions Stent patency was significantly better for endoscopic ultrasound-guided hepaticogastrostomy with bridging. However, future prospective studies are needed.

Outcomes of partially covered self-expandable metal stents with different uncovered lengths in endoscopic ultrasound-guided hepaticogastrostomy: a Japanese retrospective study

BACKGROUND/AIMS

The optimal length of the uncovered portion of partially covered self-expandable metal stents (PCSEMSs) used in endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) remains unclear. This study investigated the safety and efficacy of PCSEMSs with different uncovered lengths, with a focus on stent migration and time to recurrent biliary obstruction (RBO).

METHODS

Outcomes of patients undergoing EUS-HGS using PCSEMSs with 5-mm and 20-mm uncovered portions at our institution from January 2016 to December 2021 were compared.

RESULTS

Sixty-two patients underwent EUS-HGS using PCSEMS (5/20-mm uncovered portions: 32/30). Stent migration occurred only in the 5-mm group. There were no differences in RBO rates (28.1% vs. 40.0%) or median time to RBO (6.8 vs. 7.1 months) between the two groups. Median overall survival (OS) was longer in the 20-mm group (3.1 vs. 4.9 months, p=0.037) due to the higher number of patients that resumed chemotherapy after EUS-HGS (56.7% vs. 28.1%, p=0.029). Good performance status, absence of hepatic metastases, and chemotherapy after EUS-HGS were independent predictors of longer OS.

CONCLUSIONS

No migration was observed in patients treated with PCSEMS with 20-mm uncovered portions. Patients treated with PCSEMS with 20-mm uncovered portions performed at least as well as those treated with 5-mm uncovered portions in all material respects.

Safety of biliary drainage with 6-mm metallic stent for preoperative obstructive jaundice in pancreatic cancer: PURPLE SIX STUDY

BACKGROUND AND AIM

The 10-mm self-expandable metal stent (SEMS) is the standard for endoscopic transpapillary biliary drainage before pancreatic cancer surgery. However, the efficacy of stents thinner than 10 mm has not been adequately validated. Therefore, we aimed to evaluate the safety of a 6-mm fully covered SEMS (FCSEMS) for distal malignant biliary obstruction (DMBO) during preoperative chemotherapy for pancreatic cancer.

METHODS

This was a single-arm, multicenter, prospective phase II study of endoscopic transpapillary initial biliary drainage for DMBO before pancreatic cancer surgery. The primary endpoint was stent-related adverse events, and the key secondary endpoint was the non-recurrent biliary obstruction (non-RBO) rate during the observation period for both resectable (R) and borderline resectable (BR) pancreatic cancers.

RESULTS

The study enrolled 33 patients, among whom 32 received the study treatment. There were 23 and 9 cases of R and BR pancreatic cancers, respectively. The technical and clinical success rates were 97.0% and 90.1%, respectively. The stent-related adverse event rate was 3.1% (n = 1, acute pancreatitis) (95% confidential interval, 0.00-16.2), which met the criteria to be considered safe. The overall non-RBO rate during the observation period (median 96 days) was 78.1% (82.6% and 66.7% for R and BR pancreatic cancer cases, respectively).

CONCLUSIONS

The 6-mm FCSEMS is an extremely safe metallic stent with a low stent-related adverse event rate of 3.1% for preoperative biliary drainage in pancreatic cancer. It is considered the optimal stent for preoperative biliary drainage in terms of the non-RBO rate. UMIN Clinical Trial Registry (UMIN-CTR 000041704).

Feasibility and safety of a novel plastic stent designed specifically for endoscopic ultrasound-guided pancreatic duct drainage

Background and study aims Endoscopic ultrasound-guided pancreatic duct drainage (EUS-PD) is emerging as an effective alternative treatment for obstructive pancreatitis after unsuccessful endoscopic retrograde pancreatography (ERP). However, the high incidence of adverse events associated with EUS-PD (approximately 20%) remains an issue. Recently, we developed a novel plastic stent for EUS-PD, with a radiopaque marker positioned at approximately one-third of the length from the distal end of the stent and side holes positioned exclusively distal to the marker. This study aimed to evaluate the feasibility and safety of using this stent in EUS-PD. Patients and methods We retrospectively reviewed data from 10 patients who underwent EUS-PD with the novel plastic stent at the National Cancer Center Hospital between March 2021 and October 2023. Technical and clinical success, procedure times, adverse events (AEs), recurrent pancreatic duct obstruction (RPO), and time to RPO were assessed. Results Of the 10 patients, five had postoperative benign pancreaticojejunal anastomotic strictures and five had malignant pancreatic duct obstruction. The technical and clinical success rates were both 100% (10/10). An AE (self-limited abdominal pain) occurred in one patient (10.0%). Two patients (20.0%) died of their primary disease during the follow-up period (median, 44 days; range, 25-272 days). The incidence of RPO was 10.0% (1/10), and the 3-month non-RPO rate was 83.3%. Conclusions The novel plastic stent shows potential as a useful and safe tool in EUS-PD.

Computed tomography-based prediction of pancreatitis following biliary metal stent placement with the convolutional neural network

Background and study aims Pancreatitis is a potentially lethal adverse event of endoscopic transpapillary placement of a self-expandable metal stent (SEMS) for malignant biliary obstruction (MBO). Deep learning-based image recognition has not been investigated in predicting pancreatitis in this setting. Patients and methods We included 70 patients who underwent endoscopic placement of a SEMS for nonresectable distal MBO. We constructed a convolutional neural network (CNN) model for pancreatitis prediction using a series of pre-procedure computed tomography images covering the whole pancreas (≥ 120,960 augmented images in total). We examined the additional effects of the CNN-based probabilities on the following machine learning models based on clinical parameters: logistic regression, support vector machine with a linear or RBF kernel, random forest classifier, and gradient boosting classifier. Model performance was assessed based on the area under the curve (AUC) in the receiver operating characteristic analysis, positive predictive value (PPV), accuracy, and specificity. Results The CNN model was associated with moderate levels of performance metrics: AUC, 0.67; PPV, 0.45; accuracy, 0.66; and specificity, 0.63. When added to the machine learning models, the CNN-based probabilities increased the performance metrics. The logistic regression model with the CNN-based probabilities had an AUC of 0.74, PPV of 0.85, accuracy of 0.83, and specificity of 0.96, compared with 0.72, 0.78, 0.77, and 0.96, respectively, without the probabilities. Conclusions The CNN-based model may increase predictability for pancreatitis following endoscopic placement of a biliary SEMS. Our findings support the potential of deep learning technology to improve prognostic models in pancreatobiliary therapeutic endoscopy.

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Inside stent placement is suitable for preoperative biliary drainage in patients with perihilar cholangiocarcinoma

BACKGROUND/PURPOSE

Endoscopic biliary stenting (EBS) is commonly used for preoperative drainage of localized perihilar cholangiocarcinoma (LPHC). This study retrospectively compared the utility of inside stent (IS) and conventional stent (CS) for preoperative EBS in patients with LPHC.

METHODS

EBS was performed in 56 patients with LPHC. EBS involved the placement of a CS (n = 32) or IS (n = 24). Treatment outcomes were compared between these two groups.

RESULTS

Preoperative recurrent biliary obstruction (RBO) occurred in 23 patients (71.9%) in the CS group and 7 (29.2%) in the IS group, with a significant difference (p = 0.002). The time to RBO (TRBO) was significantly longer in IS than in CS (log-rank: p < 0.001). The number of stent replacements was significantly lower in IS than CS [0.38 (0-3) vs. 1.88 (0-8), respectively; p < 0.001]. Gemcitabine-based neoadjuvant chemotherapy (NAC) was administered to 26 patients (46.4%). Among patients who received NAC, TRBO was longer in IS than in CS group (log-rank: p < 0.001). The IS group had a significantly shorter preoperative and postoperative hospital stay than the CS group (20.0 vs. 37.0 days; p = 0.024, and 33.5 vs. 41.5 days; p = 0.016).　 Both the preoperative and the postoperative costs were significantly lower in the IS group than in the CS group (p = 0.049 and p = 0.0034, respectively).

CONCLUSION

Compared with CS, IS for preoperative EBS in LPHC patients resulted in fewer complications and lower re-intervention rates. The fact that the IS group had shorter preoperative and postoperative hospital stays and lower costs both preoperatively and postoperatively compared to the CS group may suggest that the use of IS has the potential to benefit not only the patient but also the healthcare system.

Risk factors for recurrent biliary obstruction following endoscopic biliary stenting in patients with unresectable ampullary cancer: A multicenter retrospective study

OBJECTIVES

Unresectable ampullary cancer (AC) is a rare disease entity. The risk factors for recurrent biliary obstruction (RBO) following endoscopic biliary stenting (EBS) for unresectable AC remain unknown. In this study we aimed to evaluate the cumulative RBO rate and to identify risk factors for RBO following palliative EBS in patients with unresectable AC.

METHODS

This multicenter retrospective observational study enrolled consecutive patients with unresectable AC who had undergone palliative EBS between April 2011 and December 2021. The cumulative rate of and risk factors for RBO following palliative EBS were evaluated via multivariate analysis.

RESULTS

The study analysis comprised 107 patients with a median age of 84 years (interquartile range 79-88 years). Plastic stents (PSs) and self-expandable metal stents (SEMSs) were placed in 53 and 54 patients, respectively. Functional success was accomplished in 104 (97.2%) patients. Of these, RBO occurred in 62 (59.6%) patients, with obstruction and complete/partial migration occurring in 47 and 15 patients, respectively. The median time to RBO was 190 days. Multivariate analysis showed that PS was associated with a higher rate of RBO compared to SEMS (hazard ratio [HR] 2.48; P < 0.01) and that the presence of common bile duct stones/sludge immediately after EBS was an independent risk factor for RBO (HR 1.99; P = 0.04).

CONCLUSIONS

The use of SEMS compared to PS during EBS reduced the time to RBO in patients with unresectable AC. Common bile duct stones/sludge immediately after EBS was a risk factor for RBO.

Braided-type stent versus laser-cut-type stent for patients with unresectable distal malignant biliary obstruction: a randomized controlled trial

BACKGROUND AND AIMS

Fully covered self-expandable metallic stents (SEMSs) are laser-cut (L) or braided (B); however, it remains unclear which approach is more effective for distal malignant biliary obstruction (DMBO). This study compared the clinical outcomes of using L-type and B-type stents because we believe that recurrent biliary obstruction (RBO) is less likely to occur with L-type stents.

METHODS

Patients diagnosed with unresectable DMBO were randomly assigned to groups L and B in a stratified block fashion, and outcomes were compared. The primary outcome was the rate of RBO within 1 year; secondary outcomes were adverse events, clinical success rate, time to RBO (TRBO), and overall survival.

RESULTS

Of the 60 enrolled participants, 56 (group L, n = 27; group B, n = 29) were included. The rates of RBO within 1 year were 44.4% and 17.2% in groups L and B, respectively (odds ratio, 2.57; 95% confidence interval [CI], 1.045-6.353). Early adverse events, which improved with conservative treatment, included pancreatitis (n = 4) in group L and pancreatitis (n = 3) and cholecystitis (n = 1) in group B (P = .913). The median TRBO (220 days [95% CI, 56-272] vs 418 days [95% CI, 232-454]) was significantly longer in group B than in group L (log-rank test, P = .0118). The median overall survival (group L, 158 days; group B, 204 days) after stenting was not significantly different between groups (P = .8544).

CONCLUSIONS

In the setting of DMBO, B-type stents are associated with less recurrent obstruction than L-type stents, although there was no difference in safety. (UMIN Clinical Trials Registry number: UMIN000027239.).

Role of advanced endoscopy in the management of inflammatory digestive diseases (pancreas and biliary tract)

The progress of endoscopic diagnosis and treatment for inflammatory diseases of the biliary tract and pancreas have been remarkable. Endoscopic ultrasonography (EUS) and EUS-elastography are used for the diagnosis of early chronic pancreatitis and evaluation of endocrine and exocrine function in chronic pancreatitis. Notably, extracorporeal shock wave lithotripsy and electrohydraulic shock wave lithotripsy have improved the endoscopic stone removal rate in patients for whom pancreatic stone removal is difficult. Studies have reported the use of self-expanding metal stents for stent placement for pancreatic duct stenosis and EUS-guided pancreatic drainage for refractory pancreatic duct strictures. Furthermore, EUS-guided drainage using a double-pigtailed plastic stent has been performed for the management of symptomatic pancreatic fluid collection after acute pancreatitis. Recently, lumen-apposing metal stents have led to advances in the treatment of walled-off necrosis after acute pancreatitis. EUS-guided biliary drainage is an alternative to refractory endoscopic biliary drainage and percutaneous transhepatic biliary drainage for the treatment of acute cholangitis. The placement of an inside stent followed by switching to uncovered self-expanding metal stents in difficult-to-treat cases has been proposed for acute cholangitis by malignant biliary obstruction. Endoscopic transpapillary gallbladder drainage is an alternative to percutaneous transhepatic gallbladder drainage for severe and some cases of moderate acute cholecystitis. EUS-guided gallbladder drainage has been reported as an alternative to percutaneous transhepatic gallbladder drainage and endoscopic transpapillary gallbladder drainage. However, it is important to understand the advantages and disadvantages of each drainage method and select the optimal drainage method for each case.

Comparison of covered self-expandable metallic stents with 12-mm and 10-mm diameters for unresectable malignant distal biliary obstructions: a prospective randomized trial

BACKGROUND AND AIMS

Covered self-expandable metallic stents have longer patency than uncovered self-expandable metallic stents for unresectable malignant distal biliary obstruction because of the prevention of tumor ingrowth, and they are removable during reintervention. One main cause of recurrent biliary obstruction in covered self-expandable metallic stents is sludge formation, which can be prevented by using large-bore stents. We evaluated the treatment results of 12-mm and 10-mm covered self-expandable metallic stents for unresectable malignant distal biliary obstructions using a randomized controlled trial.

METHODS

This study was conducted between May 2016 and January 2019 and included 81 consecutive patients with unresectable malignant distal biliary obstruction. The primary endpoint was the rate of nonrecurrent biliary obstruction at 6 months after stent placement.

RESULTS

The primary endpoint in the 12-mm group was significantly higher than that in the 10-mm group (P = .0369). Therefore, the median time to recurrent biliary obstruction was 172 days in the 12-mm group and 120 days in the 10-mm group. The median time to recurrent biliary obstruction in the 12-mm group was significantly longer than that in the 10-mm group (P = .0168). Using the 12-mm covered self-expandable metallic stents and receiving chemotherapy were factors affecting the rate of recurrent biliary obstruction in the multivariate analysis.

CONCLUSIONS

The 12-mm covered self-expandable metallic stents provide a longer time to recurrent biliary obstruction than do 10-mm covered self-expandable metallic stents for managing unresectable malignant distal biliary obstruction. (Clinical trial registration number: UMIN000016911.).

A novel fully covered metal stent for unresectable malignant distal biliary obstruction: results of a multicenter prospective study

BACKGROUND/AIMS

Endoscopic self-expandable metal stent (SEMS) placement is currently the standard technique for treating unresectable malignant distal biliary obstructions (MDBO). Therefore, covered SEMS with longer stent patency and fewer migrations are required. This study aimed to assess the clinical performance of a novel, fully covered SEMS for unresectable MDBO.

METHODS

This was a multicenter single-arm prospective study. The primary outcome was a non-obstruction rate at 6 months. The secondary outcomes were overall survival (OS), recurrent biliary obstruction (RBO), time to RBO (TRBO), technical and clinical success, and adverse events.

RESULTS

A total of 73 patients were enrolled in this study. The non-obstruction rate at 6 months was 61%. The median OS and TRBO were 233 and 216 days, respectively. The technical and clinical success rates were 100% and 97%, respectively. Furthermore, the rate of occurrence of RBO and adverse events was 49% and 21%, respectively. The length of bile duct stenosis (<2.2 cm) was the only significant risk factor for stent migration.

CONCLUSIONS

The non-obstruction rate of a novel fully covered SEMS for MDBO is comparable to that reported earlier but shorter than expected. Short bile duct stenosis is a significant risk factor for stent migration.

Impact of temperature-controlled endobiliary radiofrequency ablation for inoperable hilar cholangiocarcinoma: A propensity score-matched analysis

Background and study aims Endobiliary radiofrequency ablation (RFA) can be an effective palliative treatment, but few studies have evaluated its outcomes for malignant obstruction in the hilar bile duct, which has a thin wall and complex duct-vascular contacts. We evaluated the efficacy and safety of temperature-controlled endobiliary RFA, which can reduce the risk of unintentional thermal injury by maintaining the temperature of the ablation segment, in the treatment of inoperable hilar cholangiocarcinoma (CCA). Patients and methods After propensity score matching, 64 patients with inoperable hilar CCA were categorized to the RFA + stent group (endobiliary RFA with stenting; n=32) or stent-only group (stenting only; n=32). The evaluated outcomes were the median time to recurrent biliary obstruction (RBO), overall survival (OS), and adverse events (AEs). Results Technical success was achieved in all patients. The clinical success rate was 93.8% in the RFA + stent group and 87.5% in the stent-only group ( P =0.672). The median time to RBO was 242 days in the RFA + stent group and 168 days in the stent-only group ( P =0.031). The median OS showed a non-significant tendency to be higher in the RFA + stent group (337 versus 296 days; P =0.260). Overall AE rates were comparable between the two groups (12.5% vs 9.4%, P =1.000). Conclusions Temperature-controlled endobiliary RFA resulted in favorable stent patency without increasing the rate of AEs but it did not significantly increase OS in patients with inoperable hilar CCA (Clinical trial registration number: KCT0008576).

Comparison of unilateral and bilateral intraductal plastic stent placement for unresectable malignant hilar biliary obstruction: A propensity score-matched cohort analysis

BACKGROUND

Although intraductal plastic stent (IS) placement is an effective treatment for unresectable malignant hilar biliary obstruction (UMHBO), the effectiveness of unilateral and bilateral IS drainage remains controversial. This retrospective study investigated the effectiveness of bilateral IS placement for UMHBO using the propensity score matching method.

METHODS

Patients who underwent transpapillary endoscopic stenting for UMHBO were analyzed for technical and clinical success, adverse events, and time to recurrent biliary obstruction (TRBO).

RESULTS

A total of 321 patients were enrolled in the study with 27 patients in each unilateral and bilateral IS group in the propensity score-based cohort. Technical success was 100%, while clinical success was 93% and 96% in the unilateral and bilateral IS groups, respectively (p = 1.0). Cholecystitis occurred in 4% and 7%, respectively (p = 1.0). The median TRBO was shorter in the unilateral group (129 [5-383] days) than that in the bilateral group (226 [16-563] days) (p = .0281). Bilateral IS placement was an independent long TRBO factor (hazard ratio [HR] 0.46; 95% confidence interval [CI]: 0.21-0.97; p = .041).

CONCLUSIONS

Unilateral and bilateral IS placement had high technical and clinical success rates in primary stent placement. However, bilateral IS placement showed a longer TRBO. Bilateral IS placement may be a good option for initial UMHBO drainage.

A rare incidence of a hepatic artery pseudoaneurysm following plastic biliary stent insertion

Hepatic artery pseudoaneurysms have been reported to occur in approximately 1% of cases after metal stenting for malignant biliary obstruction. In contrast, only a few cases have been reported as complications after plastic stenting for benign biliary disease. We report a 61-year-old man with cholangitis who presented with a rare complication of hemobilia after implantation of 7 Fr double pigtail plastic biliary stents. No bleeding was observed approximately one month after biliary stent tube removal. Contrast-enhanced CT scan revealed a circularly enhanced lesion (5 mm in diameter) in the arterial phase at the tip of the previously inserted plastic bile duct stent. Color Doppler ultrasonography enhanced the lesion and detected arterial blood flow inside. He was diagnosed with a hepatic artery pseudoaneurysm. However, he had no risk factors such as prolonged catheterization, severe cholangitis, liver abscess, or long-term steroid use. Superselective transarterial embolization using two metal microcoils was successfully completed without damage to the surrounding liver parenchyma. If hemobilia is suspected after insertion of a plastic bile duct stent, immediate monitoring using contrast-enhanced computed tomography or Doppler ultrasonography is recommended.

The novel technique of drainage stenting using a tapered sheath dilator in endoscopic ultrasound-guided biliary drainage

During endoscopic ultrasound-guided biliary drainage (EUS-BD), there is a risk for bile leakage until stent deployment, which can result in severe peritonitis, particularly when passing a drainage stent becomes challenging despite tract dilation. There is no established method or dedicated device to optimize EUS-BD. Therefore, we have developed a novel stent deployment technique using the tapered sheath dilator. To address the safety and technical aspects of the EUS-BD technique, we retrospectively analyzed 11 consecutive patients who underwent EUS-BD using the tapered sheath dilator. The procedure involved the insertion of a guidewire, followed by mechanical dilation using the tapered sheath dilator. Subsequently, the inner catheter was removed and drainage stents (up to 6 Fr in diameter) were deployed through the outer sheath. We found a 100% technical success rate for tract dilation and stent deployment; moreover, all patients achieved clinical success. The median time for dilation was 40 s (range, 8-198), whereas the median time from dilation to stent deployment was 10 min (range, 6-19). Notably, no cases of bile leakage or peritonitis were observed. In conclusion, the use of the integrated device for tract dilation and stent delivery system might provide a safe and straightforward technique for drainage stenting during EUS-BD.

Side-by-side placement of fully covered metal stents versus conventional 7F plastic stents in malignant hilar biliary obstruction: Prospective randomized controlled trial

OBJECTIVES

We aimed to evaluate the efficacy and safety of metal stents compared with plastic stents when bilateral side-by-side stents were deployed for malignant hilar biliary obstruction (MHBO).

METHODS

Fifty patients with unresectable advanced MHBO were randomly assigned to the metal stent (MS, n = 25) or plastic stent group (PS, n = 25). Fully covered self-expandable metal stents with 6 mm diameter and plastic stents with either 7F straight or double pigtail were used for MS and PS groups, respectively. Time to recurrent biliary obstruction (TRBO) was evaluated as the primary outcome.

RESULTS

Both groups had 100% technical success rates; 88% and 76% of clinical success rates were obtained in MS and PS, respectively. Although stent migrations were more frequent in MS than PS (48% vs. 16%, P = 0.02), the mean TRBO was significantly longer in MS (190 days; 95% confidence interval [CI] 121-260 days vs. 96 days; 95% CI 50-141 days, P = 0.02). The placement of plastic stents (hazard ratio 2.42; 95% CI 1.24-4.73; P = 0.01) was the only significant risk factor associated with TRBO in multivariable analysis. The rates of adverse events were similar between the two groups (difference 0%; 95% CI -25% to 25%; P > 0.99).

CONCLUSIONS

During bilateral side-by-side deployment in MHBO, the use of metal stents appears to be preferable to plastic stents in terms of TRBO, despite a higher frequency of stent migration.

Outcomes of 6-mm diameter fully covered self-expandable metal stents for preoperative biliary drainage in pancreatic cancer

Background

10-mm self-expandable metal stents (SEMSs) are commonly used for preoperative biliary drainage in pancreatic cancer. However, smaller diameter SEMSs have attracted attention with the attempt to reduce stent-related adverse events (AEs).

Methods

We retrospectively analyzed consecutive borderline resectable pancreatic cancer patients who underwent neoadjuvant therapy and fully covered SEMS (FCSEMS) placement from April 2015 to May 2023. The primary outcome was stent-related non-event rate (NER), which was defined as the rate of completion of surgery without developing any preoperative events (recurrent biliary obstruction [RBO] or stent-related AEs). Secondary outcomes included stent-related AEs, causes of RBO, and cumulative incidence of RBO. Risk factors for pancreatitis, RBO, and stent migration were also examined.

Results

A total of 76 patients were included (6-mm group: 23; 10-mm group: 53). Stent-related NER (57% vs. 64%, p = 0.610), stent-related AEs (4% vs. 15%, p = 0.263), overall RBO rates (39% vs. 23%, p = 0.168), cumulative incidence of RBO (hazard ratio, 2.24; 95% confidence interval, 0.95-5.25; p = 0.065) were not significantly different between the two groups. Tumor involvement of the pancreatic duct was identified as a risk-reducing factor for pancreatitis, while an FCSEMS diameter of 6 mm was not identified as a risk factor for RBO and stent migration.

Conclusions

Stent-related NER was not significantly affected by FCSEMS diameter. Further studies are needed to confirm the usefulness of 6-mm diameter FCSEMS for preoperative biliary drainage in patients with borderline resectable pancreatic cancer.

Efficacy of Short-Course Antibiotic Therapy for Acute Cholangitis With Positive Blood Cultures: A Retrospective Study

BACKGROUND

Short-term treatment of acute cholangitis is sufficient for cure compared with the standard treatment duration. Whether this short-course antimicrobial therapy is effective in patients with acute cholangitis with positive blood cultures has not been fully investigated. This study assessed whether patients with acute cholangitis could achieve successful outcomes with a three-day or shorter antimicrobial treatment period, even with a positive blood culture.

METHODS

This single-center retrospective study involved patients with acute cholangitis, defined according to the Tokyo Guidelines 2018 for any cause, who underwent successful biliary drainage and completed a seven-day or shorter antimicrobial treatment. Patients were categorized into six groups based on the duration of antibiotic use (short or standard) after endoscopic retrograde cholangiopancreatography and blood culture findings (positive, negative, or no collection). The primary outcome was the clinical cure rate, defined as no initial presenting symptoms by day 14 after biliary drainage and no recurrence or death by day 30. Secondary outcomes included a three-month recurrence rate and length of hospital stay.

RESULTS

In total, 389 cases were selected, and 27 patients (6.9%) undergoing short-course therapy tested positive for blood culture. The clinical cure rate (n=25, 92.6%) in this group was comparable to that in the other groups. For the three-month recurrence rate (n=1, 3.7%) and median hospital stay (six days), this group's outcomes were either better or similar to those of the other groups.

CONCLUSIONS

For cases of successful drainage in acute cholangitis, even with positive blood cultures, short-term antibiotic therapy may be appropriate.

Antimicrobial therapy outcomes in acute cholangitis: Hilar multiple obstructions versus single hilar and common bile duct obstructions

Background and Aim

The appropriate duration of antimicrobial therapy for acute cholangitis (AC) arising from multiple hilar biliary obstructions as opposed to simple obstruction in the extrahepatic bile duct has not been established. This study assessed the efficacy of the duration of antimicrobial treatments in the Tokyo Guidelines 2018 for AC based on the cause and site of obstruction.

Methods

This single-center retrospective study involved patients with AC who underwent successful biliary drainage and completed a 7-day or shorter antimicrobial treatment. Patients were categorized into three groups: Group 1, bile duct stone or benign obstruction; Group 2, simple biliary obstruction due to malignancy; and Group 3, multiple hilar biliary obstruction due to malignancy. The primary outcome was clinical cure rate, and the secondary outcomes were 3-month recurrence rate and length of hospital stay.

Results

A total of 373 patients were selected. Patients in Group 3 were younger or had Charlson Comorbidity Index ≥4, and had fewer positive blood cultures. In Group 3, the clinical cure rate (87.1%) and 3-month recurrence rate (32.3%) were less favorable than those in the other groups. In Group 1, the clinical cure rate was significantly higher (98.1%, P = 0.02) with a much lower 3-month recurrence rate of only 3.4% (P < 0.001) than that in the other groups. The median hospital stay for all groups was 7 days.

Conclusion

This study suggests that the outcomes in Group 3 may be worse than those in Groups 1 or 2, regardless of the duration of the antibiotic treatment.

A Novel Method of Calculating the Drained Liver Volume Using a 3D Volume Analyzer for Biliary Drainage of Unresectable Malignant Hilar Biliary Obstruction

OBJECTIVES

In patients with unresectable malignant hilar biliary obstruction (UMHBO), drainage of ≥ 50% liver volume correlates with better clinical outcomes. Accurately measuring the liver volume to be drained by biliary stents is required. We aimed to develop a novel method for calculating the drained liver volume (DLV) using a 3D volume analyzer (3D volumetry), and assess the usefulness for drainage in patients with UMHBO.

METHODS

Three-dimensional volumetry comprises the following steps: (1) manual tracing of bile duct using 3D imaging system; (2) 3D reconstruction of bile duct and liver parenchyma; and (3) calculating DLV according to the 3D distribution of bile ducts. Using 3D volumetry, we reviewed data of patients who underwent biliary drainage for UMHBO, calculated the DLV, and determined the association between DLV and biliary drainage outcome.

RESULTS

There were 104 eligible cases. The mean DLV was 708 ± 393 ml (53% ± 21%). and 65 patients (63%) underwent drainage of   ≥50% liver volume. The clinical success rate was significantly higher in patients with DLV ≥ 50% than in patients with DLV < 50% (89% vs. 28%, P < 0.001). The median time to recurrence of biliary obstruction (TRBO) and survival time were significantly longer in patients with DLV ≥ 50% than in patients with DLV < 50% (TRBO, 292 vs. 119 days, P = 0.03; survival, 285 vs. 65days, P = 0.004, log-rank test, respectively).

CONCLUSIONS

Three-dimensional volumetry, a novel method to calculate DLV accurately according to bile duct distribution was useful for drainage in UMHBO patients.