Novel self-expandable stent-based endobiliary radiofrequency ablation for unresectable malignant biliary obstruction.

BACKGROUND AND AIMS: Endobiliary radiofrequency ablation (RFA) is an emerging endoscopic palliative adjunctive therapy used for the local treatment of unresectable malignant biliary obstruction (MBO). However, irregular ablation ranges caused by insufficient electrode-to-bile duct contact pose a significant obstacle. The aim was to investigate the feasibility of a self-expandable stent (SES)-based electrode with a customized RFA generator in the porcine liver and common bile duct (CBD). METHODS: A SES-RFA system with polarity-switching was developed to perform endobiliary RFA. The ablation ranges of 20 ablation protocols were evaluated to validate the feasibility of the newly developed RFA system in the porcine liver. Nine of the 20 ablation protocols were selected for evaluation in the porcine CBD with cholangiography, endoscopy, and histological and immunohistochemical analysis. RESULTS: The SES-RFA system with polarity-switching was successfully constructed and demonstrated high accuracy and reproducibility. The ablation area was clearly identified between the two SESs. The ablation ranges and degree of mucosal damage including TUNEL- and HSP70-positive depositions increased proportionally with ablation protocols in the porcine liver and CBD (all P < .05). Ablation length and depth linearly increased with ablation protocols from 8.74 ± 0.25 to 31.25 ± 0.67 mm and 1.61 ± 0.09 to 11.94 ± 0.44 mm, respectively. CONCLUSIONS: The SES-RFA system with polarity-switching between electrodes provided an even circumferential area of ablation and enhanced ablation depth between the electrodes. This novel endobiliary RFA system is a promising modality for local ablation in patients with unresectable MBO.

ERCP for the initial management of malignant biliary obstruction - real world data on 596 procedures.

AIMS: To evaluate outcomes of ERCP as first-line management in patients with malignant biliary obstruction (MBO) of all causes and stages, reflecting a real-life setting. METHODS: Retrospective observational study of patients with ERCP as the first-line management of MBO at Oslo University Hospital between 2015 and 2021. Primary outcome measure was a ≥ 50% decrease from the pre-procedural bilirubin within 30 days after ERCP. Secondary outcome measures were technical success of ERCP, complications and overall mortality. RESULTS: A total of 596 patients were included, median age 70 years. ASA score was ≥ III in 67% of patients. The most common cancers causing MBO were pancreatic cancer (52%), metastatic lesions (20%) and cholangiocarcinoma (16%). The primary outcome measure was achieved in 62% of patients. With endoscopic access, overall technical success was 80% with 85% for the distal extrahepatic group, 71% for the perihilar, 40% for the intrahepatic and 53% for multiple level MBOs. Reinterventions were performed in 27% of the patients. Complications occurred in 15% of the patients, including post-ERCP pancreatitis in 9%. Most complications were of minor/moderate severity (81%). Overall mortality was 33% within the first 90 days. Patients deceased by the end of the study period (83%) had median survival of 146 days (range 1-2,582 days). CONCLUSIONS: ERCP has a high rate of clinical effect and technical success in the management of both distal extrahepatic and perihilar MBO. Our data indicate that ERCP is a valid option in the first-line management of MBO.

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).

Efficacy of multi-hole self-expandable metal stent compared to fully covered and uncovered self-expandable metal stents in patients with unresectable malignant distal biliary obstruction: a propensity analysis.

BACKGROUND AND AIMS: Self-expandable metal stent (SEMS) insertion is the standard palliative treatment for unresectable malignant extrahepatic biliary obstruction (MBO). Drawbacks of conventional fully covered SEMS (FCSEMS) and uncovered SEMS (USEMS) include stent migration and tumor ingrowth, respectively. This study aimed to compare stent patency in MBO with the newly design multi-hole SEMS (MHSEMS), which has multiple small side holes in the stent membrane, with conventional FCSEMS and UCSEMS. PATIENTS AND METHODS: This retrospective study using a propensity score matching design and stent patency times of 40 patients with MHSEMS was compared to 40 and 34 patients with FCSEMS and UCSEMS during the same period, respectively. Secondary outcomes were procedure-related adverse events, clinical success rate, time to recurrent biliary obstruction (RBO), and etiology of RBO. RBO was compared using Kaplan-Meier analysis. RESULTS: Baseline characteristics after matching were comparable among the 3 groups. RBO rates were 21%, 37%, and 55% for MHSEMS, FCSEMS, and UCSEMS, respectively (p = 0.014), at a mean time of 479, 353, and 306 days, respectively (MHSEMS vs UCSEMS, p = 0.002). Rate of tumor ingrowth was highest in the UCSEMS group (42.4% vs 13.2% in MHSEMS; p = 0.005 and vs 0% in FCSEMS; p < 0.001). Stent migration rate was highest in the FCSEMS group at 15.8% vs 2.6% in MHSEMS (p = 0.047) and 0% in UCSEMS (p = 0.005). CONCLUSION: MHSEMS provided the longest stent patency time with lowest RBO rate compared to conventional SEMS by showing a lower stent migration rate than FCSEMS and a lower tumor ingrowth rate than UCSEMS.

Endoscopic ultrasound-guided hepaticogastrostomy vs. antegrade metal stent placement keeping an access route in patients with malignant biliary obstruction.

BACKGROUND: Few studies have compared endoscopic ultrasound (EUS)-guided hepaticogastrostomy (HGS) with EUS-guided antegrade metal stent placement (AGMS). The purpose of this study was to compare times to recurrent biliary obstruction (TRBO) in patients who underwent HGS using metal stents (MS) and those who underwent AGMS keeping access routes with plastic stents (AGMS-AR). METHODS: This study retrospectively evaluated consecutive patients who underwent HGS or AGMS between September 2016 and December 2022. TRBO, overall survival (OS), and adverse event (AE) rates were compared in the two groups. The risk factors for RBO were determined using a multivariable Cox proportional hazards model. RESULTS: This study included 32 patients in the HGS group and 30 in the AGMS-AR group. Technical success rate was significantly higher in the HGS than in the AGMS-AR group (100 vs. 80%; P = 0.009). The technical success rate without tract dilation was significantly higher in the AGMS-AR than in the HGS group (83 vs. 38%; P < 0.001). RBO rates were significantly higher in the HGS than in the AGMS-AR group (53 vs. 17%; P = 0.024), whereas AE rates did not differ significantly. TRBO differed significantly in the HGS and AGMS-AR groups (159 days vs. not reached, P = 0.011), whereas OS did not differ significantly. Multivariable analysis revealed that HGS was an independent risk factor for RBO (hazard ratio, 6.48, P = 0.014). CONCLUSION: TRBO was significantly longer in patients who underwent AGMS with PS than HGS. AGMS with PS may be effective after the failure of ERCP in patients with malignant biliary obstruction.

Impact of sarcopenia on recurrent biliary obstruction after EUS-guided biliary drainage in patients with malignant biliary obstruction.

BACKGROUND AND AIMS: Sarcopenia is an important prognostic factor for cancer patients. The aim of this study was to assess the ability of sarcopenia to predict recurrent biliary obstruction (RBO) in patients with unresectable cancer after EUS-guided biliary drainage (EUS-BD). METHODS: The study enrolled 113 patients who underwent EUS-BD using the self-expandable metal stent (SEMS) for unresectable malignant biliary obstruction (MBO) between April 2016 and December 2021 at Wakayama Medical University Hospital. The skeletal muscle index at the third lumbar spine level (L3) was calculated from computed tomography images. We analyzed the cumulative incidence of RBO at 180 days after stent insertion. Univariate and multivariate analyses were performed to identify variables significantly associated with RBO. RESULTS: Seventy-six patients were assigned to the sarcopenia group, and 37 were assigned to the non-sarcopenia group. The 180-day cumulative incidence of RBO was 11% in the non-sarcopenia group and 29% in the sarcopenia group (p = 0.034). The time to RBO was significantly shorter for the sarcopenia group (p = 0.028; Gray's test). Multivariate analyses identified sarcopenia as an independent prognostic factor for RBO (present vs absent; HR 4.61; 95% CI 1.76-12.10, p = 0.001). The rates of biliary sludge/food impaction were significantly higher in the sarcopenia group for the causes of RBO (p = 0.048). There were no significant differences between the sarcopenia and the non-sarcopenia groups with respect to related EUS-BD adverse events. CONCLUSION: Sarcopenia is an independent indicator of RBO in patients with MBO who receive EUS-BD with SEMS.

Retrospective comparative study of new slim-delivery and conventional large-cell stents for stent-in-stent methods for hilar malignant biliary obstruction.

OBJECTIVES: Endoscopic management of unresectable hilar malignant biliary obstruction (HMBO) is technically challenging, and effectiveness of stent-in-stent using large-cell, metal stents was reported. A new, large-cell stent with a 6F tapered delivery system was recently developed. The aim of this study was to compare clinical outcomes of slim-delivery and conventional large-cell stents. METHODS: This was a multicenter retrospective comparative study of stent-in-stent methods using slim-delivery stents (Niti-S Large Cell SR Slim Delivery [LC slim-delivery]) and conventional stents (Niti-S large-cell D-type; LCD) for unresectable HMBO. RESULTS: Eighty-three patients with HMBO were included; 31 LC slim-delivery and 52 LCD. Overall technical and clinical success rates were 100% and 90% in LC slim-delivery group and 98% and 88% in LCD group. Use of the LC slim-delivery was associated with shorter stent placement time in the multiple regression analysis, with a stent placement time of 18 and 23 min in LC slim-delivery and LCD groups, respectively. The early adverse event (AE) rate of LC slim-delivery was 10%, with no cholangitis or cholecystitis as compared to 23% in the LCD group. Recurrent biliary obstruction (RBO) rates and time to RBO were comparable between the two groups: 35% and 44%, and 8.5 and 8.0 months in LC slim-delivery and LCD groups, respectively. The major cause of RBO was tumor ingrowth (82%) in the LC slim-delivery group and sludge (43%) and ingrowth (48%) in LCD group. CONCLUSION: Stent-in-stent methods using LC slim-delivery shortened stent placement time with low early AE rates and comparable time to RBO in patients with HMBO.

Endoscopic ultrasound-guided gallbladder drainage as a first approach for jaundice palliation in unresectable malignant distal biliary obstruction: Prospective study.

OBJECTIVES: Endoscopic retrograde cholangiopancreatography (ERCP) represents the gold standard for jaundice palliation in patients with distal malignant biliary obstruction (DMBO). Biliary drainage using electrocautery lumen apposing metal stent (EC-LAMS) is currently a well-established procedure when ERCP fails. In a palliative setting the endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) could represent an easy and valid option. We performed a prospective study with a new EC-LAMS with the primary aim to assess the clinical success rate of EUS-GBD as a first-line approach to the palliation of DMBO. METHODS: In all, 37 consecutive patients undergoing EUS-GBD with a new EC-LAMS were prospectively enrolled. Clinical success was defined as bilirubin level decrease >15% within 24 h and >50% within 14 days after EC-LAMS placement. RESULTS: The mean age was 73.5 ± 10.8 years; there were 17 male patients (45.9%). EC-LAMS placement was technically feasible in all patients (100%) and the clinical success rate was 100%. Four patients (10.8%) experienced adverse events, one bleeding, one food impaction, and two cystic duct obstructions because of disease progression. No stent-related deaths were observed. The mean hospitalization was 7.7 ± 3.4 days. Median overall survival was 4 months (95% confidence interval 1-8). CONCLUSION: Endoscopic ultrasound-guided gallbladder drainage with the new EC-LAMS is a valid option in palliative endoscopic biliary drainage as a first-step approach in low survival patients with malignant jaundice unfit for surgery. A smaller diameter EC-LAMS should be preferred, particularly if the drainage is performed through the stomach, to avoid potential food impaction, which could result in stent dysfunction.

Secondary uncovered versus fully-covered metal stents for the management of occluded stent in unresectable distal malignant biliary obstruction.

INTRODUCTION: Self-expandable metallic stents (SEMS) have been widely placed for unresectable distal malignant biliary obstruction (UDMBO). However, the dysfunction rate is 19-40% and its treatment is controversial. We aimed asses the efficacy and safety of a secondary biliary stents (uncovered (UC) versus fully-covered (FC) stent) for the management of occluded SEMS. PATIENTS AND METHODS: Between 2015 and June 2023, 41 patients with UDMBO underwent secondary biliary stent placement as "stent-in-stent" (20 FCSEMS and 21 UCSEMS). The primary outcomes were technical and clinical success of SEMS placement. Secondary outcomes included adverse events (AEs), patency and survival. Patients were prospectively followed until death or loss of follow-up. RESULTS: Technical (100% vs 85.5%) and clinical (100% vs 95.2%) success rates were similar in FCSEMS and UCSEMS groups. The median follow-up period was 510 days (range 290-630). The median duration of stent patency of FCSEMS (220 days, IQR 137.5-442.5) was longer than UCSEMS (150 days, IQR 110-362.5) (P=0.395), although stent dysfunction within 6 months was not different between groups. Multivariate analysis indicated that sex (HR=0.909, 0.852-0.970), antitumor treatment (HR=0.248, 0.032-0.441), stent patency (HR=0.992, 0.986-0.998) and clinical success (HR=0.133, 0.026-0.690) were significant factors for overall survival. There were no remarkable differences in AEs. CONCLUSIONS: The placement of additional biliary stent using the stent-in-stent method is an effective and safe rescue treatment for patients with UDMBO and occluded stent. In addition, the use of FCSEMS compared UCSEMS has unclear benefits regarding stent patency and overall survival.

Endoscopic retrograde stent drainage therapies for malignant biliary obstruction: the distal opening of stent location above or across the duodenal papilla? A systematic review and meta-analysis.

OBJECTIVE: To systematically evaluate the efficacy and safety of the method of placing the distal stent opening above the duodenal papilla (hereinafter referred to Above method) for endoscopic retrograde stent internal drainage in MBO patients. METHODS: PubMed, Embase, Web of science and Cochrane databases were searched to identify clinical studies comparing the stent distal opening mounted above the papilla and across the papilla (hereinafter referred to Across method), Comparison indicators included stent patency, stent occlusion rate, clinical success rate, overall complication rate, postoperative cholangitis rate, and overall survival. Revman5.4 software was used for meta-analysis, funnel plot and publication bias and Egger's test were completed by Stata14.0 software. RESULTS: A total of 11 clinical studies (8 case-control studies, 3 RCT studies) were included, with a total of 751 patients (318 cases in the Above group and 433 cases Across group). The overall patency of Above method was longer than that of Across method (HR = 0.60, 95%CI [0.46-0.78], p < 0.001). Subgroup analysis showed statistical difference using plastic stent (HR = 0.49, 95%CI [0.33,0.73], p < 0.001). Inversely, there didn't exist significant difference in which metal stent were adopted (HR= 0.74, 95%CI [0.46,1.18], p = 0.21). Similarly, there also without statistical difference between patients with plastic stent placed above the papilla and metal stent mounted Across the papilla (HR = 0.73, 95%CI [0.15,3.65], p = 0.70). Moreover, the overall complication rate of the Above method was lower than that of the Across method (OR = 0.48,95%CI [0.30,0.75], p = 0.002). On the contrary, the differences of stent occlusion rate (OR = 0.86,95%CI [0.51,1.44], p = 0.56), overall survival (HR = 0.90, 95%CI [0.71,1.13]), p = 0.36), the clinical success rate (OR = 1.30, 95%CI [0.52,3.24], p = 0.57) and postoperative cholangitis rats (OR = 0.73, 95%CI [0.34,1.56], p = 0.41) were not statistically significant. CONCLUSIONS: The distal opening of the stent can be placed above the duodenal main papilla for eligible MBO patients who receiving endoscopic retrograde stent drainage treatment, which can effectively prolong the patency duration when plastic stent is used, and reduce the overall risk of complications.

Comparison of therapeutic efficacy and treatment costs of self-expandable metal stents and plastic stents for management of malignant biliary obstruction.

BACKGROUND: According to the European Society of Gastrointestinal Endoscopy guidelines, self-expandable metal stents (SEMSs) are preferable to plastic stents (PSs) in the management of pancreatic cancer, regardless of cancer stage. The aim of this study was to compare the therapeutic efficacy and treatment costs of SEMS and PS in the management of malignant biliary obstruction. METHODS: One hundred and thirty-five patients who underwent endoscopic stent placement were retrospectively enrolled and divided into PS (41 patients), primary SEMS (39 patients) and secondary SEMS (55 patients) groups. We determined the technical and functional success rate, stent patency, and cumulative treatment cost. RESULTS: A total of 111 SEMSs and 153 PSs were placed with similar technical (100% vs. 98.69%) and functional success rate (90.10% vs. 86.27%) but with different stent patency (10.28 vs. 22.16 weeks; p < 0.001). Multiple PS implantations and larger stent diameter increased the length of stent patency compared to 7-Fr PSs (10.88 vs. 10.55 vs. 7.63 weeks, respectively). The cumulative treatment cost of patients with different survival times did not differ significantly between groups, however, among patients surviving 2-4 months it was higher in PS group than primary SEMS and secondary SEMS groups (2888€ vs. 2258€ vs. 2144€, respectively, p = 0.3369) due to increased number of biliary reintervention (2.08 ± 1.04 vs. 1.20 ± 0.42 vs. 1.50 ± 0.53; p < 0.0274) and longer hospital stay (15.77 ± 10.14 vs. 8.70 ± 7.70 vs. 8.50 ± 6.17 days, p = 0.0527). CONCLUSIONS: In view of treatment costs, the consequences of illness, and the processes of the health care system, SEMS implantation is recommended regardless of patients' life expectancy.

Factors associated with patency of self-expandable metal stents in malignant biliary obstruction.

INTRODUCTION: Endoscopic self-expandable metal stent (SEMS) placement is the key endoscopic treatment for unresectable malignant biliary obstruction. The benefit of covered SEMS over uncovered SEMS remains unknown as are risk factors for SEMS dysfunction. This study aimed to determine the factors associated with patency of SEMS. METHODS: Patients with unresectable malignant biliary obstruction who underwent endoscopic SEMS placement at Ramathibodi Hospital, during January 2012 to March 2021 were included. Patient characteristics, clinical outcomes and patency of SEMS were collected. The primary outcome were stent patency and factors associated with patency of SEMS. The factors were analyzed by univariate and multivariate analyses. Median days of stent patency, median time of patient survival, rate of reintervention and complications after SEMS placement were collected. RESULTS: One hundred and fourteen patients were included. SEMS dysfunction was found in 37 patients (32.5%). Size of cancer (Hazard ratio (HR), 1.20, (95% CI 1.02, 1.40), p 0.025), presence of stones or sludge during SEMS placement (Hazard ratio (HR), 3.91, (95% CI 1.74, 8.75), p 0.001), length of SEMS, 8 cm (HR 2.96, (95% CI 1.06, 8.3), p 0.039), and total bilirubin level above 2 mg/dL at one month after SEMS placement (HR 1.14, (95% CI 1.06, 1.22), p < 0.001) were associated with SEMS dysfunction. The median stent patency was 97 days. The median patient survival was 133 days, (95% CI 75-165). The rate of reintervention was 86% in patients with SEMS dysfunction. CONCLUSION: The size of cancer, presence of stones or sludge during SEMS placement, the length of SEMS, and total bilirubin level above 2 mg/dL at 1 month after SEMS placement were associated with SEMS dysfunction. The median time of stent patency were not statistically different in each type of stent, covered stent, partially covered stent and uncovered stent. Median survival time of patients did not associate with SEMS patency or dysfunction.

Biliary self-expandable metallic stent combined with iodine-125 seeds in the treatment of malignant biliary obstruction (Bismuth type I or II).

BACKGROUND: The purpose of this research was to evaluate the safety and efficacy of a self-expandable metallic stent (SEMS) combined with iodine-125 (125I) seeds in the treatment of Bismuth type I or II malignant biliary obstruction (MBO). METHODS: The clinical data of 74 cases of MBO treated with percutaneous SEMS combined with 125I seeds (combination group) and 81 cases of MBO treated with SEMS implantation alone (control group) in our hospital from January 2015 to December 2019 were retrospectively analyzed. The short-term and long-term efficacy of the two groups were compared. Multivariate Cox regression analysis was used to analyze the factors affecting the surgical efficacy and survival rate. RESULTS: The liver blood test results of both groups improved at one week and one month post-stent insertion. No significant difference was established in the short-term efficacy or complications between the two groups (P = NS). Improved stent patency was observed in the combined group, 9.01 ± 4.38 months versus 6.79 ± 3.13 months, respectively (P < 0.001). Improved survival was also noted in the combined group 12.08 ± 5.38 months and 9.10 ± 4.16 months, respectively (P < 0.001). Univariate and multivariate analyses showed that the type of biliary stent and liver metastasis were independent factors affecting survival. CONCLUSION: The implementation of SEMS combined with 125I seeds resulted in significantly longer stent patency and survival times than that of SEMS implantation alone, which is thus worthy of clinical promotion and application.

Endoscopic Ultrasound-Guided Hepaticogastrostomy with Antegrade Stenting Without Dilation Device Application for Malignant Distal Biliary Obstruction in Pancreatic Cancer.

BACKGROUND: Endoscopic ultrasound-guided hepaticogastrostomy with antegrade stenting (EUS-HGAS) is a promising therapeutic option for malignant distal biliary obstruction (MDBO) in the event of transpapillary approach failure. Eliminating the fistula dilation step may further decrease the incidence of adverse events (AE) and simplify the procedure. AIMS: This study focused on MDBO associated with pancreatic cancer and aimed to examine the utility of EUS-HGAS without the use of any dilation devices. METHODS: This retrospective study investigated consecutive patients in whom the transpapillary approach had failed or was difficult, and who underwent EUS-HGAS without dilation device usage, using a tapered small-diameter catheter, ultrathin delivery system, and tapered dedicated plastic stent. The outcomes of this study included the technical success, clinical success, AE incidence, and recurrent biliary obstruction (RBO) associated with the procedure. RESULTS: During the study period, EUS-HGAS without dilation device usage was attempted for 57 patients with MDBO due to pancreatic cancer. The technical and clinical success rates were 91.2% (52/57) each. The median procedural time was 25 min. The rates of early and late AE besides RBO were 3.5% (2/57) and 1.9% (1/52), respectively. The incidence rate of RBO was 30.8% (16/52), and the median time to RBO was 245 days. The rate of successful endoscopic reintervention for RBO via the fistula was 100% (16/16). CONCLUSIONS: EUS-HGAS without the use of dilation devices showed good technical feasibility with a low AE rate. It may be a useful option for MDBO associated with pancreatic cancer when the transpapillary approach is difficult.

Meta-analysis on clinical outcomes of suprapapillary versus transpapillary stent insertion in malignant biliary obstruction.

BACKGROUND/AIMS: Endoscopic biliary stenting is an essential treatment for malignant biliary obstruction (MBO). However, the optimal location for the placement of metal stents (MS) or plastic stents (PS) during the management of MBO, whether above (suprapapillary) or across (transpapillary) the sphincter of Oddi (SO), has not been thoroughly evaluated. This meta-analysis aims to compare the clinical outcomes associated with endoscopic retrograde cholangiopancreatography (ERCP)-guided biliary stents placed above and across the SO in patients with MBO. METHODS: A comprehensive search of electronic databases was carried out to identify studies published from inception to April 2022. The clinical outcomes examined including stent patency, stent occlusion, and overall adverse events (AEs) such as cholangitis, post-ERCP pancreatitis (PEP), cholecystitis, stent migration, and bleeding. The selection of a random-effects model or fixed-effects model was based on the presence of heterogeneity. RESULTS: A total of 12 articles involving 751 patients were analyzed. The findings showed that the suprapapillary approach had longer stent patency compared to the transpapillary approach (mean difference: 38.58; 95% confidence interval 16.02-61.14, P < 0.0001). Additionally, the suprapapillary approach was associated with a lower risk of stent occlusion and overall AEs (P = 0.04, P = 0.002, respectively), particularly in the incidence of PEP (P = 0.009). The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. The subgroup analyses indicated that suprapillary PS had a significant decrease in the incidence of stent occlusion and longer stent patency, while suprapillary MS had a significant decrease in the incidence of overall AEs and PEP than the transpapillary approach. CONCLUSION: Compared with the transpapillary approach, the suprapapillary stent had superiority in longer stent patency, lower rates of stent occlusion and overall AEs, and notably, a lower incidence of PEP. The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. Further large-scale randomized controlled studies are needed to confirm our findings. REGISTRATION NO: CRD42022336435.

Long-term outcomes of duckbill-type anti-reflux metal stents versus conventional covered metal stents in reinterventions after covered biliary metal stent dysfunction in unresectable pancreatic cancer.

BACKGROUND: The use of duckbill-type anti-reflux metal stents (DMS) in reinterventions after covered metal stent (CMS) dysfunction has been reported in patients with distal malignant biliary obstruction (MBO). However, the superiority of DMS over conventional CMS (c-CMS) has not been established. Therefore, we conducted this retrospective study to evaluate the long-term efficacy and safety of DMS as a second stent in comparison with c-CMS. METHODS: We investigated consecutive patients with distal MBO due to unresectable pancreatic cancer who underwent reintervention after dysfunction of initial biliary CMS at our institution. We compared causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), adverse events (AEs), and reintervention rates of DMS and c-CMS in this stenting. RESULTS: A total of 76 patients were included (DMS 41 and c-CMS 35). While overall RBO rates were similar between the two groups (46% vs. 63%, p = 0.172), RBO due to non-occlusion cholangitis tended to be less frequent in the DMS group than in the c-CMS group (2% vs. 14%, p = 0.089). Median TRBO was significantly longer in the DMS group (286 days vs. 112 days, p = 0.029). DMS was identified as the only significant risk factor for TRBO (hazard ratio, 0.52; p = 0.044). Overall AE rates were significantly lower in the DMS group (2% vs. 23%, p = 0.010), with non-occlusion cholangitis being the most common AE in the c-CMS group. Endoscopic reintervention was successfully performed in all patients in both groups, despite failed stent removal in 15% of patients in DMS group. CONCLUSIONS: DMS was associated with a significantly longer TRBO and lower rate of AEs compared with c-CMS in reinterventions after initial CMS dysfunction. DMS may be preferable to c-CMS as a second stent after biliary CMS dysfunction.

A Risk Prediction Model for Post-endoscopic Retrograde Cholangiopancreatography Pancreatitis After Stent Insertion for Malignant Biliary Obstruction: Development and Validation.

OBJECTIVES: Pancreatitis is the most common complication of post-endoscopic retrograde cholangiopancreatography (ERCP). There are currently no prediction models, particularly for post-ERCP pancreatitis (PEP) after biliary stent placement due to malignant biliary obstruction (MBO). To that end, we aim to develop and validate a predictive model for PEP. METHODS: We retrospectively analyzed the data of patients who underwent ERCP for biliary stent placement due to MBO at the Second Affiliated Hospital of Harbin Medical University from January 1, 2014 to August 31, 2021. The eligible patients were randomly allocated to the development and validation cohorts. A prediction model was built using the development cohort, and the model's effect was validated using a validation cohort. RESULTS: A total of 1524 patients were enrolled, including 1016 in the development cohort and 508 in the validation cohort, with an overall PEP rate of 7.1%. The model's predictors included acute pancreatitis history, the absence of pancreatic duct dilation, nonpancreatic cancer, difficult cannulation, and pancreatic injection. The area under the curve (AUC) in the development cohort was 0.810, and the incidence of PEP in the low-risk, medium-risk, and high-risk groups was 1.53%, 9.12%, and 36.36%, respectively. Meanwhile, the AUC of the validation cohort was 0.781, and the incidence of PEP in the low-risk, medium-risk, and high-risk groups was 4.17%, 8.75%, and 41.67%, respectively. CONCLUSIONS: This study was the first to build and validate a risk prediction model, especially for PEP after biliary stent placement due to MBO. Moreover, this model might assist clinicians in identifying high-risk patients and help implement preventive measures in a more timely manner.

Endoscopic Ultrasound-Guided Naso-gallbladder Drainage Using a Dedicated Catheter for Acute Cholecystitis After Transpapillary Metal Stent Placement for Malignant Biliary Obstruction.

BACKGROUND: Acute cholecystitis is a significant adverse event after self-expandable metal stent (SEMS) placement for malignant biliary obstruction (MBO); however, no appropriate treatment strategy has been established for its management. AIMS: This study aimed to examine the feasibility and utility of endoscopic ultrasound-guided naso-gallbladder drainage (EUS-NGBD) for the management of acute cholecystitis occurring after SEMS placement. METHODS: This retrospective study investigated consecutive patients with acute cholecystitis after SEMS placement for unresectable MBO, in whom EUS-NGBD was attempted. The study outcomes included technical success, clinical success, procedure time, adverse event, and cholecystitis recurrence, associated with the procedure. RESULTS: During the study period, EUS-NGBD was performed for SEMS-related acute cholecystitis in 30 patients with MBO. The technical and clinical success rates were 96.7% (29/30) and 96.6% (28/29), respectively. The median procedure time was 15 min, and rate of procedure-related adverse event was 3.3% (1/30). The median duration from the procedure to tube removal was 9 days. No adverse events were observed after removal. The median hospitalization duration after the procedure was 14 days, and the median duration to the (re-)start of chemotherapy from cholecystitis onset was 13 days. The median overall survival after EUS-NGBD was 123 days, and the rate of cholecystitis recurrence until death was 4.2% (1/28). CONCLUSIONS: This study demonstrated that EUS-NGBD possesses good technical and clinical feasibility with an acceptable adverse event rates and short hospitalization and chemotherapy withdrawal period. Therefore, EUS-NGBD may be a good option for the treatment of SEMS-related cholecystitis in patients with MBO.

Comparable Efficacy of Laser-Cut and Braided Self Expanding Metallic Biliary Stent: A Systematic Review and Meta-Analysis.

BACKGROUND AND AIMS: In patients with unresectable malignant biliary obstruction (MBO), endoscopic biliary drainage is the treatment of choice. Self-expanding metallic stents (SEMS) are mainly used for this purpose, and data is limited on the comparative outcomes of laser-cut versus braided SEMS. Herein, we performed the first systematic review and meta-analysis to study the effectiveness and safety of braided and laser-cut SEMS in MBO. METHODS: Multiple databases, including Medline, Scopus, and Embase, were searched (in May 2022) using specific terms for studies evaluating the outcomes of braided and laser-cut SEMS in MBO. Outcomes of interest were technical and clinical success, recurrent biliary obstruction, and adverse events. Standard meta-analysis methods were employed using the random-effects model. I2% heterogeneity was used to assess the heterogeneity. RESULTS: Seven studies were included in the final analysis. (Laser-cut: 271 patients, 46% females, mean age 70 years; and braided: 282 patients, 47% females, mean age 72 years). The pooled rate of technical success and clinical success with laser-cut SEMS was 99% (95% CI [95-99; I2 = 0%]), 86% [60-96; I2 = 74%], and 98% [96-99; I2 = 0%], 89% [74-95; I2 = 78%] with braided. The pooled rate of recurrent biliary obstruction with laser-cut SEMS was 26% [14-43; I2 = 88%] and 12% [5-27; I2 = 56%) with braided. Pooled total adverse events were 11% [5-21; I2 = 77%] in laser-cut and 12% [6-24; I2 = 63%] in braided. CONCLUSION: Our meta-analysis demonstrates similar clinical outcomes with laser-cut and braided SEMS in MBO. Given the comparable performance, a cost-effectiveness analysis might help in choosing one type versus another in patients with MBO.

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

BACKGROUND: There is no consensus on the necessity of endoscopic sphincterotomy (ES) to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) after endoscopic stenting in patients with malignant biliary obstruction. We investigated the incidence of PEP after endoscopic biliary stenting for malignant biliary obstruction with or without ES in a multicenter prospective cohort study. METHODS: We enrolled 807 patients who underwent endoscopic biliary stenting for malignant biliary obstruction with a native papilla at 36 hospitals between April 2017 and March 2018. The incidence of PEP in patients with or without ES was compared for subgroups based on stent type, placement method, and patient background. Univariate and multivariate analysis was performed to investigate the incidence of PEP in all stenting patients. RESULTS: Plastic and metal stents (MS) were inserted in 598 and 209 patients, respectively. The incidence of PEP in patients with or without ES was 7.9% and 7.4%, respectively among all stenting patients. The incidences of PEP with or without ES in plastic stent insertion patients, patients with MS insertion, stent insertions across the papilla, stent insertions across the papilla in patients without main pancreatic duct obstruction, and fully covered MS insertions across the papilla were compared. There was no overall significant difference in the incidence of PEP between those with or without ES. Multivariate logistic regression analysis for the incidence of PEP in all stenting patients revealed obstruction of the main pancreatic duct at the pancreatic head and epinephrine spraying on the papilla were significant factors; there was no significant difference in the incidence of PEP between patients with or without ES. CONCLUSION: Endoscopic sphincterotomy may not contribute to the prevention of PEP after endoscopic biliary stenting for malignant biliary obstruction, even in cases of insertion with a fully covered MS across the papilla.