Median Time To Recurrent Biliary Obstruction Research Articles

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

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. 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. There were no significant intergroup differences in rates of technical or clinical success, adverse events, RBO occurrence, oroverall survival. The median TRBO was significantly shorter in theaPS 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). 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.

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

Background and AimsFully covered self-expandable metallic stents (SEMS) are laser-cut (L) or braided (B); however, which is more effective for distal malignant biliary obstruction (DMBO) has been unclear. We 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. MethodsPatients 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. ResultsOf the 60 enrolled participants, 56 (group L: 27, group B: 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=0.913). The median TRBO (220 days [95% CI: 56-272] versus 418 days [95% CI: 232-454]) was significantly longer in group B than in group L (log-rank test, p=0.0118). The median overall survival (L: 158 days, B: 204 days) after stenting was not significantly different between the groups (p=0.8544). ConclusionsIn the setting of DMBO, braided (B)-type stents are associated with less recurrent obstruction than laser-cut-type (L) stents, although there was no difference in safety.

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

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

The evaluation of bilateral stenting using braided or laser-cut self-expandable metallic stent for malignant hilar biliary obstruction.

Bilateral self-expandable metallic stent (SEMS) placement for unresectable malignant hilar biliary obstruction (UMHBO) is an effective option for biliary drainage with long-term stent patency. Laser-cut and braided SEMS can be used for bilateral SEMS placement. This study aimed to clarify any differences in the clinical features and proper use of the laser-cut and braided SEMS placement using the stent-in-stent method for UMHBO. In this study, 78 patients who underwent bilateral stent-in-stent SEMS placement for UMHBO were included. The patients were divided into the laser-cut (n = 33) and braided groups (n = 45). Both groups were compared for technical and clinical success, adverse events (AEs), time to recurrent biliary obstruction (TRBO), overall survival, and endoscopic reintervention (ERI). There were no significant differences in technical and clinical success rates (laser-cut vs. braided group, 97% vs. 95.6%, P = 1.0), AEs (21.2% vs. 15.6%. P = 0.56), median TRBO (242days vs. 140days, P = 0.36), and median overall survival (654days vs. 675days, P = 0.58). ERI was required in 15 patients in the laser-cut group and in 20 patients in the braided group. The technical and clinical success rates of ERI (60% vs. 85%) were not significantly different (P = 0.13); however, the median ERI procedure time was significantly longer in the laser-cut group (38min) than in the braided group (22min; P = 0.02). No significant difference in initial SEMS placement was noted between the laser-cut and braided groups; however, the laser-cut group required a longer ERI procedure time than that required by the braided group. The use of braided SEMS may be a convenient option for ERI.

Impact of sarcopenia on biliary drainage during neoadjuvant therapy for pancreatic cancer.

Since the usefulness of neoadjuvant chemo(radiation) therapy (NAT) for pancreatic cancer has been demonstrated, recurrent biliary obstruction (RBO) in patients with pancreatic cancer with a fully covered self-expandable metal stent (FCSEMS) during NAT is expected to increase. This study investigated the impact of sarcopenia on RBO in this setting. Patients were divided into normal and low skeletal muscle index (SMI) groups and retrospectively analyzed. Patient characteristics, overall survival, time to RBO (TRBO), stent-related adverse events, and postoperative complications were compared between the two groups. A Cox proportional hazard model was used to identify the risk factors for short TRBO. A few significant differences were observed in patient characteristics, overall survival, stent-related adverse events, and postoperative complications between 38 patients in the normal SMI group and 17 in the low SMI group. The median TRBO was not reached in the normal SMI group and was 112 days in the low SMI group (p=0.004). In multivariate analysis, low SMI was the only risk factor for short TRBO, with a hazard ratio of 5.707 (95% confidence interval, 1.148-28.381; p=0.033). Sarcopenia was identified as an independent risk factor for RBO in patients with pancreatic cancer with FCSEMS during NAT.

Utility of bilateral intraductal plastic stent for malignant hilar biliary obstruction compared with bilateral self-expandable metal stent: a propensity score–matched cohort analysis

Intraductal plastic stent (IS) placement for unresectable malignant hilar biliary obstruction (UMHBO) is an effective option for biliary drainage. However, the effectiveness of bilateral IS placement compared with bilateral self-expandable metal stent (SEMS) placement remains unclear. Overall, 301 patients with UMHBO were enrolled; 38 patients underwent bilateral IS placement (IS group) and 38 patients underwent SEMS placement (SEMS group) in the propensity score-based cohort. Both groups were compared for technical and clinical success, adverse events (AEs), recurrent biliary obstruction (RBO), time to RBO (TRBO), overall survival (OS), and endoscopic reintervention (ERI). No significant differences were observed between the groups regarding technical and clinical success, AEs and RBO occurrence rates, TRBO, or OS. The median initial endoscopic procedure time was significantly shorter in the IS group (23 vs 49 minutes, P< .01). ERI was performed on 20 and 19 patients in the IS and SEMS groups, respectively. The median ERI procedure time was significantly shorter in the IS group (22 vs 35 minutes, P= .04). Median TRBO after ERI with plastic stent placement tended to be longer in the IS group (306 vs 56 days, P= .068). A Cox multivariate analysis showed that the IS group was the significant related factor for TRBO after ERI (hazard ratio, .31; 95% confidence interval, .25-.82; P= .035). Bilateral IS placement can reduce the duration of the endoscopic procedure and provide sufficient stent patency both initially and after ERI stent placement, and the stents are removable. Bilateral IS placement is considered a good option for initial UMHBO drainage. (Clinical trial registration number: UMIN000050546.).

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

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

Outcomes of Intraductal Placement of Covered Metal Stents for Unresectable Distal Malignant Biliary Obstruction

Intraductal self-expandable metal stent (SEMS) placement may prolong stent patency by reducing duodenobiliary reflux. This study aimed to evaluate the efficacy and safety of this biliary drainage method in patients with unresectable distal malignant biliary obstruction (MBO). Consecutive patients with unresectable MBO who underwent initial covered SEMS placement between 2015 and 2022 were retrospectively reviewed. We compared the causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), adverse events (AEs), and reintervention rates between two biliary drainage methods (SEMSs placed above and across the papilla). A total of 86 patients were included (above: 38 and across: 48). Overall RBO rates (24% vs. 44%, p = 0.069) and median TRBO (11.6 months vs. 9.8 months, p = 0.189) were not significantly different between the two groups. The frequency of overall AEs was similar between the two groups in the entire cohort, but was significantly lower in patients with non-pancreatic cancer (6% vs. 44%, p = 0.035). Reintervention was successfully performed in the majority of patients in both groups. Intraductal SEMS placement was not associated with a prolonged TRBO in this study. Larger studies are warranted to further evaluate the benefit of intraductal SEMS placement.

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.

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. 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. 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 (286days vs. 112days, 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. 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.

Effect of ursodeoxycholic acid after self-expandable metal stent placement in malignant distal biliary obstruction: a propensity score–matched cohort analysis

Sludge occlusion is a primary reason for recurrent biliary obstruction (RBO) after self-expandable metallic stent (SEMS) placement. However, the efficacy of ursodeoxycholic acid (UDCA) for SEMS occlusion remains unexplored to date. This study aimed to evaluate the efficacy of UDCA after SEMS placement for malignant distal biliary obstruction (MDBO). Three hundred fifty-four patients were included, of which 60 received UDCA. Additionally, we conducted a propensity score-matched cohort analysis on 110 patients with SEMS placement for MDBO to reduce selection bias. Patients were categorized into 2 groups of 55 each, based on whether they received UDCA. In the UDCA group, the treatment was administered for more than a month. The primary endpoint was the time to RBO (TRBO) after SEMS placement. The secondary endpoint was to evaluate SEMS occlusion rate and early adverse events (AEs). The cumulative SEMS occlusion rate was 41.8% and 18.2% in the groups with and without UDCA, respectively (P= .0119). Median TRBO was significantly longer in the control group than in the UDCA group (528 vs 154 days, P= .0381). In the multivariate analysis, UDCA administration was identified as the independent risk factor for reducing TRBO (hazard ratio, 2.28; 95% confidence interval, 1.06-4.88; P= .0348). The overall early AE rate showed insignificant differences between groups. Administering UDCA after SEMS placement was not efficacious for prolonging the TRBO in MDBO. Moreover, administering UDCA beyond a month might increase the risk of stent sludge occlusion. (Clinical trial registration number: UMIN000046862.).

The Feasibility of Whole-Liver Drainage with a Novel 8 mm Fully Covered Self-Expandable Metal Stent Possessing an Ultra-Slim Introducer for Malignant Hilar Biliary Obstructions.

Background: In the case of an unresectable malignant hilar biliary obstruction (MHBO), the optimal drainage method has not yet been established. Recently, an 8 mm, fully covered, self-expandable metal stent (FCSEMS) with an ultra-slim introducer has become available. In this article, the results of whole-liver drainage tests using this novel FCSEMS for MHBO are reported. Methods: Unresectable MHBOs up to Bismuth IIIa with strictures limited to the secondary branches were eligible. The proximal end of the stent was placed in such a way as to avoid blocking the side branches, and the distal end was placed above the papilla when possible. Consecutive patients treated between April 2017 and January 2021 were retrospectively analyzed. The technical and functional success rates, rates and causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), revision for RBO, and adverse events (AEs) were evaluated. Results: Eleven patients (Bismuth I/II/IIIa: 1/7/3) were enrolled. Two stents were placed in nine patients and three were placed in two patients. Both the technical and functional success rates were 100%. RBO occurred in four (36%) patients due to sludge formation. Revision was performed for three patients, with the successful removal of all stents. The median TRBO was 187 days, and no late AEs other than the RBO occurred. Regarding the distal position of the stent, the RBO rate was significantly lower (14.3% vs. 75%, p = 0.041) and the cumulative TRBO was significantly longer (median TRBO: not reached vs. 80 days, p = 0.031) in the case of the placement above the papilla than the placement across the papilla. Conclusion: For unresectable MHBOs of Bismuth I, II, and IIIa, whole-liver drainage with a novel 8 mm FCSEMS possessing an ultra-slim introducer was feasible and potentially safe, with favorable stent patency. Placement above the papilla might be preferrable to placement across the papilla.

Potential significance of uncovered self-expandable metal stents for distal malignant biliary obstruction: A propensity score-adjusted competing risk regression analysis.

ObjectivesSelection criteria for self‐expandable metal stents (SEMSs) with or without cover during palliative treatment of distal malignant biliary obstruction (DMBO) remain unclear. We evaluated factors associated with time to recurrent biliary obstruction (TRBO) in fully covered SEMSs (FCSEMSs) and uncovered SEMSs (UCSEMSs).MethodsWe retrospectively analyzed consecutive patients with DMBO who received a SEMS. TRBO was determined using the Kaplan–Meier analysis, and complications were compared between the FCSEMS and UCSEMS groups. After TRBO‐associated factors were extracted using multivariate competing‐risks regression (CRR), propensity score‐adjusted CRRs were performed to verify their robustness.ResultsThere were 180 patients (66 FCSEMSs and 114 UCSEMSs) enrolled in this study. There was no significant difference between median TRBO in the FCSEMS and UCSEMS groups (275 vs. 255 days, p = 0.67). Complications were more frequent in the FCSEMS than UCSEMS group (21.2% vs. 8.8%; p = 0.023). Multivariate CRR for TRBO‐associated factors revealed that “pancreatic ductal carcinoma (PDAC) treated with UCSEMS” was the only independent predictor of TRBO (p = 0.03). Similarly, the propensity score‐adjusted CRRs showed no significant difference in TRBO in “FCSEMS” vs “UCSEMS” (p = 0.96); however, there was a significant difference in “PDAC using UCSEMS” vs “other” (p = 0.043). In the palliative care group including any DMBO without chemotherapy, the first quartile of the TRBO of UCSEMS was 100 days.ConclusionsUCSEMSs are a possible option for both patients with DMBO arising from PDAC and for patients with any DMBO receiving palliative care who should avoid SEMS‐related complications.

Usefulness of the laser-cut, fully covered, self-expandable metallic stent for endoscopic ultrasound-guided hepaticogastrostomy.

Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) has many associated adverse events. We evaluated the clinical efficacy and safety of the laser-cut, fully covered, self-expandable metallic stent (FCSEMS) for this procedure. This single-center, retrospective study included cases where EUS-HGS with a laser-cut FCSEMS was performed for malignant biliary obstruction. Technical and clinical success, time to recurrent biliary obstruction (TRBO), procedure time, adverse events, and re-interventions were evaluated. There were 95 eligible cases. Technical and clinical success rates were 100.0% and 95.8%, respectively. Median TRBO was 398 days. RBO causes were hyperplasia (7.4%), debris (3.2%), and migration (4.2%). Adverse events occurred in nine cases (9.5%). Non-occlusion and focal cholangitis occurred in four cases (4.2%) each. Nineteen patients (20%) underwent combined EUS-HGS (CH) procedures: antegrade stenting, bridging methods, plastic stent anchoring in SEMS, and EUS-hepaticoduodenostomy. The solely EUS-HGS (SH) group had significantly longer median TRBO than the CH group (398 vs 246 days, P=.04). There were no significant differences in adverse events between the two groups. Re-intervention was performed in 29 cases (technical success rate: 100.0%). Laser-cut FCSEMS can be safely placed in the bile duct and easily applied during re-intervention, making it useful in EUS-HGS.

Comparison of outcomes between secondary fully covered and uncovered self-expandable metal stents in the treatment of recurrent biliary obstruction of pancreatic cancer.

The overall survival (OS) of pancreatic cancer (PC) has been prolonged by advances in chemotherapy, and the number of cases of recurrent biliary obstruction (RBO) after self-expandable metal stent (SEMS) placement is expected to increase. We herein compared outcomes between secondary fully covered SEMS (FC) and uncovered SEMS (UC) for RBO of PC with FC placed as the 1st SEMS. Between May 2010 and March 2021, 62 PC patients who underwent SEMS exchange to FC (n = 34) or UC (n = 28) for RBO were retrospectively analyzed. Patient characteristics, OS, time to RBO (TRBO), and stent-related adverse events were compared between the FC and UC groups. Cox's proportional hazard model was used to identify risk factors for RBO with the 2nd SEMS. There was a significant difference between the FC and UC groups only in the 2nd SEMS diameter. Median OS and TRBO were 195 and 238days in FC patients and 306 and 455days in UC patients, respectively, with no significant differences between the two groups. No significant differences were observed in the stent-related adverse event rate. In multivariate analyses, only the 2nd SEMS diameter was significant (P = 0.009). Median TRBO were 455, 238, and 103days in 10-mm UC, 10-mm FC, and 8-mm UC patients, with 10-mm UC patients having significantly longer TRBO than 10-mm FC and 8-mm UC patients (P = 0.020 and 0.001). SEMS exchange to 10-mm UC may be appropriate for RBO of PC with FC as the 1st SEMS.

Endoscopic ultrasound‐guided choledochoduodenostomy without fistula dilation using a stent with a 5.9‐Fr delivery system: Comparison to a conventional procedure with fistula dilation

ObjectivesTo evaluate the feasibility and safety of endoscopic ultrasound‐guided choledochoduodenostomy (EUS‐CDS) without fistula dilation using a novel self‐expandable metal stent (SEMS).MethodsThis retrospective study examined patients who underwent EUS‐CDS for malignant distal biliary obstruction between October 2017 and May 2021 at the National Cancer Center, Japan. The primary outcome was a technical success without fistula dilation. Secondary outcomes were the overall technical success, clinical success, adverse events (AEs), procedure time, recurrent biliary obstruction (RBO), and time to RBO (TRBO).ResultsForty‐one patients were enrolled; 31 patients underwent EUS‐CDS with fistula dilation using a conventional SEMS with 7.5–8.5‐Fr delivery system (conventional SEMS group), and 10 patients underwent EUS‐CDS without fistula dilation using the novel SEMS with a 5.9‐Fr delivery system (novel SEMS group). In the novel SEMS group, the rate of technical success without fistula dilation was 90%. There were no differences in overall technical success (100% vs. 97%, p = 1.00), clinical success (80% vs. 90%, p = 0.58), and overall AEs (10% vs. 23%, p = 0.65) rates between the novel and conventional SEMS groups. In the novel SEMS group, no early AEs were observed and no bile leakage into the abdominal cavity was observed on the computed tomography scan after the procedure. The median procedure time was significantly shorter in the novel SEMS group (17 min vs. 24 min, p = 0.03). RBO and median TRBO did not differ between the 2 groups.ConclusionsEUS‐CDS without fistula dilation using the novel SEMS with a 5.9‐Fr delivery system is technically feasible, straightforward, quick, and safe.

Usefulness of self-expandable metal stents for malignant biliary obstruction using a short-type single-balloon enteroscope in patients with surgically altered anatomy.

To evaluate the efficacy and safety of self-expandable metal stent (SEMS) placement for unresectable malignant biliary obstruction (MBO) using a short-type single-balloon enteroscopy (short SBE) in patients with surgically altered anatomy (SAA). The technical success rate, clinical success rate, recurrent biliary obstruction (RBO), time to RBO (TRBO), procedure related adverse events, and reintervention after RBO were evaluated from September 2011 to June 2020. Thirty-seven patients (11 patients with distal MBO and 26 with hilar MBO) who underwent SEMS placement were included in the analysis. The technical and clinical success rates were 100% and 94.6%. Seven patients underwent bilateral stenting (partial stent-in-stent placement) for hilar MBO. The RBO rate was 13.5% (5/37) and the median TRBO was 212 (interquartile range [IQR], 154-296) days. No food impaction occurred in this study. Procedure related adverse events occurred in 5.4% (2/37) of cases. Reintervention was attempted in five patients and all succeeded (four patients underwent SEMS replacement, and one underwent plastic stent placement). SEMS placement for unresectable MBO using a short SBE in patients with SAA is effective and safe in similar ways to that in patients with normal anatomy in terms of bilateral stenting, stent patency, and reintervention.

One-step versus two-step distal self-expandable metal stent placement: A multicenter prospective randomized trial.

Two methods of transpapillary covered self-expandable metal stent (SEMS) placement are used for distal malignant biliary obstruction (MBO): after initial drainage by plastic stent (two-step method) and without previous drainage (one-step method). In total, 90 patients with unresectable pancreatic cancer and distal MBO were enrolled in this prospective multicenter randomized study and allocated to one-step (n=45) and two-step (n=45) groups. The main outcome was the time to recurrent biliary obstruction (TRBO). Secondary outcomes were the rates of early and late adverse events, survival time, the time required for bilirubin level reduction, and cost-effectiveness. The median TRBO did not differ significantly between the one-step and two-step groups (not available vs 314days, P=0.134). SEMS migration occurred significantly more frequently in the two-step group (14.3% vs 0%, P=0.026). No significant difference was observed between groups in early (7.3% vs 14.3%, P=0.483) or late (12.2% and 11.9%, P=1) adverse events other than RBO, survival time (P=0.104), or the median number of days required to reach a bilirubin level considered to be acceptable for chemotherapy administration (<3mg/dL; P=0.881). The total costs of stent placement and reintervention were significantly lower in the one-step SEMS group (3347 vs 5465 US dollars, P<0.001). The superiority of TRBO with two-step SEMS placement was not demonstrated. One-step SEMS placement might be a promising method from the viewpoints of cost-effectiveness and less invasiveness (UMIN-CTR clinical trial registration number: UMIN000016010).

Feasibility of biliary stenting to distal malignant biliary obstruction using a novel designed metal stent with duckbill-shaped anti-reflux valve.

Anti-reflux metal stent (ARMS) has been used to prevent recurrent biliary obstruction (RBO) due to sludge formation or food impaction. However, the most suitable ARMS remains to be identified. This study aimed to evaluate the feasibility, safety, and efficacy of biliary drainage using duckbill-shaped ARMS (D-ARMS). This was a multicenter, retrospective observational study conducted at three Japanese tertiary institutions. Patients with distal malignant biliary obstruction who underwent biliary stenting using D-ARMS were eligible to participate. Technical success, functional success, adverse event (AE), and time to RBO (TRBO) were evaluated. Thirty patients underwent biliary stenting using D-ARMS from December 2018 to October 2019. The technical success rate and functional success rate were 93% and 87%, respectively. However, nonvisibility of the markers at the tip of the metal stent or spontaneous extension was occasionally observed, making biliary stenting using D-ARMS difficult. Early AE occurred in 10% of the patients including cholangitis and pancreatitis. During the median postprocedural observation time of 5.1months (range, 0.8-22.8), RBO occurred in 33% and the median TRBO was 261days. As for reintervention, D-ARMS could be extracted in 67% of the patients with RBO. However, the stent was torn off on removal in half of the patients. Although some modifications are still needed, D-ARMS was feasible and safe for biliary drainage, and sufficient TRBO was achieved. Subsequent multi-institutional studies involving a larger number of patients and a longer follow-up period are warranted to validate the present results.

Utility of laser-cut covered self-expandable metal stents for unresectable malignant distal biliary obstruction: a single-center experience.

Few reports have evaluated the effectiveness of laser-cut, covered, self-expandable metal stents (LC-CSEMS) for unresectable malignant distal biliary obstruction (MDBO) and whether reintervention is feasible after placement. We describe our experience with LC-CSEMS placement for unresectable MDBO. Patients undergoing LC-CSEMS placement for unresectable MDBO from November 2014 to December 2018 were reviewed. Recurrent biliary obstruction (RBO), median time to RBO (TRBO), and reintervention were analyzed. 52 patients who underwent LC-CSEMS placement for unresectable MDBO were included in the analysis. The RBO rate was 15 % and the median TRBO was 445 days. Reintervention was attempted in nine patients and stent removal was successful in eight patients. Our experience suggests the effectiveness of LC-CSEMS in patients with unresectable MDBO in terms of stent patency and feasibility of reintervention.

Antireflux Metal Stent for Initial Treatment of Malignant Distal Biliary Obstruction.

Objectives To compare the use of an antireflux metal stent (ARMS) with that of a conventional covered self-expandable metal stent (c-CSEMS) for initial stenting of malignant distal biliary obstruction (MDBO). Materials and Methods We retrospectively investigated 59 consecutive patients with unresectable MDBO undergoing initial endoscopic biliary drainage. ARMS was used in 32 patients and c-CSEMS in 27. Technical success, functional success, complications, causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), and reintervention were compared between the groups. Results Stent placement was technically successful in all patients. There were no significant intergroup differences in functional success (ARMS [96.9%] versus c-CSEMS [96.2%]), complications (6.2 versus 7.4%), and RBO (48.4 versus 42.3%). Food impaction was significantly less frequent for ARMS than for c-CSEMS (P = 0.037), but TRBO did not differ significantly between the groups (log-rank test, P = 0.967). The median TRBO was 180.0 [interquartile range (IQR), 114.0–349.0] days for ARMS and 137.0 [IQR, 87.0–442.0] days for c-CSEMS. In both groups, reintervention for RBO was successfully completed in all patients thus treated. Conclusion ARMS offers no advantage for initial stent placement, but food impaction is significantly prevented by the antireflux valve.