Management of occluded metal stents in malignant biliary obstruction: similar outcomes with second metal stents compared to plastic stents

Results of Endoscopic Treatment of Recurrent Malignant Biliary Obstruction in Patients with Self-Expanding Metal Stents

BACKGROUND AND AIM

Endoscopic biliary drainage with placement of a self-expanding metal stent (SEMS) is the preferred palliative treatment of malignant biliary obstruction. Recent advances in the treatment have prolonged survival, thus, increasing the chance of recurrent biliary obstruction (RBO) after SEMS placement. The aim of this study was to compare different endoscopic approaches in patients with a SEMS and RBO, regarding clinical success and time to RBO.

METHODS

This retrospective study included all patients with a SEMS placed because of malignant biliary strictures who underwent endoscopic retrograde cholangiopancreatography between January 2011 and December 2018. We evaluated the results of different endoscopic interventions to RBO, including insertion of a new SEMS, stent cleaning, and insertion of a plastic stent (PS).

RESULTS

From January 2011 to December 2018, 70 (22.4%) patients developed RBO requiring endoscopic reintervention (n = 105 sessions). From the 105 ERCPs, technical success, clinical success, and adverse events rates were 91,4%, 71,8%, and 7,8%, respectively. Younger age (OR = 1.11 95%CI: 1.03-1.19) and the finding of a patent SEMS (OR = 0.17 95%CI: 0.04-0.08) were predictors of clinical failure (P = 0.006 and P = 0.024, respectively). The mean patency time (in days) after endoscopic reintervention was greater for SEMSs than for PSs (417.2 [95% CI: 250.0-584.4] vs 175.2 [95% CI: 124.0-226.5], P = 0.002).

CONCLUSIONS

Correct identification and treatment of the causal factor of RBO typically lead to technical and clinical success. Placement of a second SEMS provides longer patency compared to a plastic stent if ingrowth (overgrowth) occurs.

Endoscopic management of malignant biliary obstructions

Malignant biliary obstruction (MBO), both distal and hilar, represents an ensemble of different clinical conditions frequently encountered in everyday practice. Given the frequent unresectability of the disease at presentation and the increasing indications for neoadjuvant chemotherapy, endoscopic biliary drainage is generally required during the course of the disease. With the widespread use of interventional endoscopic ultrasound (EUS) and the introduction of dedicated devices, EUS-guided biliary drainage has rapidly gained acceptance, together with transpapillary endoscopic biliary drainage and the percutaneous approach. This comprehensive review describes the current role of endoscopy for distal and hilar MBO supported by evidence, with a focus on the current hot topics in this field.

The Impact of Radiofrequency Ablation on Survival Outcomes and Stent Patency in Patients with Unresectable Cholangiocarcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Endoluminal biliary radiofrequency ablation (RFA) has been proposed as a palliative treatment for patients with malignant biliary obstruction (MBO) in order to improve stent patency and survival. However, the existing data on patients with inoperable extrahepatic cholangiocarcinoma (eCCA) are conflicting. We performed a meta-analysis of randomized trials comparing RFA plus stenting versus stenting alone in patients with inoperable eCCA. We searched for trials published in the PubMed/MEDLINE, Scopus, and Cochrane databases up to November 2023. Data extraction was conducted from published studies, and a quality assessment was carried out in accordance with the guidelines recommended by the Cochrane Collaboration. Hazard ratios (HRs) with 95% CI were estimated from the trials. The primary endpoints of interest were overall survival and stent patency. Out of 275 results, 5 randomized trials and 370 patients were included. While overall survival was not different between the groups (HR 0.62; 95% CI 0.36-1.07; p = 0.09; I2 = 80%;), the subgroup analysis of studies employing plastic stents showed a trend toward better survival in the RFA-treated group (HR 0.42; 95% CI 0.22-0.80; p = 0.009; I2 = 72%). Stent patency was improved in patients receiving RFA (HR 0.64; 95% CI 0.45-0.90; p = 0.01; I2 = 23%). Adverse events were not different between the groups (OR 1.21; 95% CI 0.69-2.12; p = 0.50; I2 = 0%). Despite the promising results, high heterogeneity and potential biases in the included studies suggest the need for further high-quality randomized trials to explore the potential cumulative effects of RFA on CCA treatment outcomes.

Uncovered versus fully covered self-expandable metal stents for the management of distal malignant biliary obstruction

BACKGROUND AND AIM

Self-expandable metal stents (SEMSs) are widely used for palliation of distal malignant biliary obstruction (dMBO). However, previous studies comparing the outcomes between uncovered SEMSs (UCSEMSs) and fully covered SEMSs (FCSEMSs) report conflicting results. This large cohort study aimed to compare the clinical outcomes between UCSEMSs and FCSEMSs for dMBO.

METHODS

A retrospective cohort study was performed in patients with dMBO who underwent either UCSEMS or FCSEMS placement between May 2017 and May 2021. Primary outcomes were rates of clinical success, adverse events (AEs), and unplanned endoscopic reintervention. Secondary outcomes were types of AEs, intervention-free stent patency, and management and outcomes of stent occlusion.

RESULTS

The cohort included 454 patients (364 in the UCSEMS group and 90 in the FCSEMS group). Median follow-up duration was 9.6 months and was similar between the 2 groups. Use of UCSEMSs and FCSEMSs had comparable clinical success (P = .250). However, use of UCSEMSs had significantly higher rates of AEs (33.5% vs 21.1%; P = .023) and unplanned endoscopic reintervention (27.0% vs 11.1%; P = .002). UCSEMSs had a higher rate of stent occlusion (26.9% vs 8.9%; P < .001) and shorter median time to stent occlusion (4.4 months vs 10.7 months; P = .002). Stent reintervention-free survival was higher in the FCSEMS group. FCSEMSs had a significantly higher rate of stent migration (7.8% vs 1.1%; P < .001), but patients in the FCSEMS group had similar rates of cholecystitis (.3% vs 1.1%; P = .872) and post-ERCP pancreatitis (6.3% vs 6.6%; P = .90). When UCSEMSs did occlude, placement of a coaxial plastic stent had a higher rate of stent reocclusion compared with coaxial SEMS placement (46.7% vs 19.7%; P = .007).

CONCLUSION

FCSEMSs should be considered for the palliation of dMBO because of lower rates of AEs, longer patency rates, and lower rates of unplanned endoscopic intervention.

Best Practices in Pancreatico-biliary Stenting and EUS-guided Drainage

Indications for endoscopic placement of endoluminal and transluminal stents have greatly expanded over time. Endoscopic stent placement is now a well-established approach for the treatment of benign and malignant biliary and pancreatic diseases (ie, obstructive jaundice, intra-abdominal fluid collections, chronic pancreatitis etc.). Ongoing refinement of technical approaches and development of novel stents is increasing the applicability and success of pancreatico-biliary stenting. In this review, we discuss the important developments in the field of pancreatico-biliary stenting, with a specific focus on endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-associated developments.

In-stent radiofrequency ablation with uncovered metal stent placement for tumor ingrowth/overgrowth causing self-expandable metal stent occlusion in distal malignant biliary obstruction: multicenter propensity score-matched study

BACKGROUND AND AIMS

In patients with unresectable malignant biliary obstruction (MBO), endoscopic drainage with a self-expandable metal stent (SEMS) is a well-established treatment, but stent patency is limited. This study aimed to evaluate the efficacy of in-stent radiofrequency ablation (IS-RFA) followed by uncovered SEMS placement for the management of occluded SEMSs.

METHODS

From 2016 to 2020, 48 patients with recurrent biliary obstruction due to tumor ingrowth or overgrowth after SEMS placement for pancreatobiliary cancer in 3 tertiary hospitals were analyzed. For distal MBO, patients in the RFA group were treated with IS-RFA and uncovered SEMS placement, and those in the control group were treated with uncovered SEMS placement alone. Patients in both groups were matched on the basis of propensity scores in a 1:1 ratio.

RESULTS

The median time to recurrent biliary obstruction (TRBO) was 117 days in the RFA group and 82.5 days in the control group (P = .029). No significant differences in median overall survival were detected between the 2 groups (170 days vs 72 days; P = .902). No significant adverse events were reported after the second SEMS placement in either group, but 2 cases of mild cholangitis were reported in the control group. Ablation was interrupted in 5 patients (35.7%) of the RFA group owing to in-stent contact, but sufficient ablative energy was delivered in the majority of the patients (92.9%) after IS-RFA was repeated in the same session.

CONCLUSIONS

IS-RFA followed by an uncovered SEMS is safe and feasible and may improve TRBO as a stent revision for occluded SEMSs in pancreatobiliary cancer.

Endoscopic versus percutaneous intervention for palliation in malignant hilar bile duct obstruction - A comparative cohort study

BACKGROUND

Biliary drainage in patients managed palliatively for malignant hilar obstruction can be achieved by endoscopic transpapillary stenting using endoscopic retrograde cholangiography (ERC) or percutaneous transhepatic stent or catheter placement using percutaneous transhepatic cholangiography (PTC). This study compares ERC and PTC drainage for malignant hilar bile duct obstruction.

METHODS

A retrospective study of drainage procedures at two academic hospitals was conducted from 2015 to 2020. Procedural success (divided into access-, bridging-, and technical success), therapeutic success, duration of therapeutic success and complications were analysed for different Bismuth-Corlette stricture types.

RESULTS

A total of 293 patients were included, 153 (52.2%) in the ERC group and 140 (47.8%) in the PTC group. Access and bridging success in the ERC and PTC groups were 83.5% vs. 97.2% (p < 0.001) and 90.2% vs. 84.5% (p = 0.119), respectively. Technical and therapeutic success were equivalent between the two groups (98.3% vs. 99.3%, p = 0.854 and 81.7% vs. 73.3%, p = 0.242). Duration of therapeutic success was longer after ERC drainage compared to PTC drainage (p = 0.009) with a 3-month gain in duration of therapeutic success after ERC drainage (p = 0.006, 95% CI [26-160]). Cholangitis rates were equivalent (21.4% vs. 24.7%, p = 0.530), pancreatitis was more common in the ERC group (9.4% vs. 0%, p < 0.001) and procedure-related deaths more common in the PTC group (6.0% vs. 15.8%, p < 0.001).

CONCLUSION

Although ERC and PTC drainage of malignant hilar obstruction were similar regarding technical and therapeutic success, ERC drainage was more durable. Outcome differences for B-C stricture types should be explored in future studies.

Role of ERCP in Malignant Hilar Biliary Obstruction

Malignant hilar biliary obstruction (MHO), an aggressive perihilar biliary obstruction caused by cholangiocarcinoma, gallbladder cancer, or other metastatic malignancies, has a poor prognosis. Surgical resection is the only curative treatment method for biliary malignancies. However, most of the patients with MHO cannot undergo surgeries on presentation because of an advanced inoperable state or a poor performance state due to old age or comorbid diseases. Therefore, palliative biliary drainage is mandatory to improve symptomatic jaundice and quality of life. Among drainage methods, endoscopic biliary drainage is the current standard for the palliation of unresectable advanced MHO. The development of stents and various accessories and advances in endoscopic techniques including endoscopic ultrasonography have facilitated primary endoscopic intervention in difficult high-grade hilar strictures. However, some issues are still under debate, such as palliation methods, appropriate stents, the number of stents, deployment methods, and additional local ablation therapies. Therefore, this review presents currently optimal endoscopic palliation methods for advanced MHO based on the reported literature.

Endoscopic Reintervention for Recurrence of Malignant Biliary Obstruction: Developing the Best Strategy

Drainage therapy for malignant biliary obstruction (MBO) includes trans-papillary endoscopic retrograde biliary drainage (ERBD), percutaneous transhepatic biliary drainage (PTBD), and trans-gastrointestinal endoscopic ultrasound-guided biliary drainage (EUS-BD). With the development of chemotherapy, many MBO cases end up needing endoscopic reintervention (E-RI) for recurrent biliary obstruction. To achieve a successful E-RI, it is necessary to understand the various findings regarding E-RI in MBO cases reported to date. Therefore, in this review, we focus on E-RI for ERBD of distal MBO, ERBD of hilar MBO, and EUS-BD. To plan an appropriate E-RI strategy for biliary stent occlusion for MBO, the following must be considered on a case-by-case basis: the urgency of the drainage, the cause of the occlusion, the original route of drainage (PTBD/ERBD/EUS-BD), the initial stent used (plastic stent or self-expandable metallic stent), and in the case of self-expandable metallic stents, the type used (fully covered or uncovered). Regardless of the original method of stent placement, if the inflammation caused by obstructive cholangitis is severe and/or the patient is in shock, PTBD should be considered as the first choice. Finally, it is important to keep in mind that in many cases, performing E-RI will be difficult.

Experimental model of occluded biliary metal stent recanalization using irreversible electroporation via a tubular catheter

PURPOSE

To demonstrate the feasibility of irreversible electroporation (IRE) for treating biliary metal stent occlusion in an experimental liver model.

METHODS AND MATERIALS

IRE was performed using an expandable tubular IRE-catheter placed in nitinol stents in the porcine liver. A 3-electrode IRE-catheter was connected to an IRE-generator and one hundred 100μs pulses of constant voltage (300, 650, 1000, and 1300 V) were applied. Stent occlusion was simulated by insertion of liver tissue both ex vivo (n = 94) and in vivo in 3 pigs (n = 14). Three scenarios of the relationship between the stent, electrodes, and inserted tissue (double contact, single contact, and stent mesh contact) were studied. Electric current was measured and resistance and power calculated. Pigs were sacrificed 72 h post-procedure. Harvested samples (14 experimental, 13 controls) underwent histopathological analysis.

RESULTS

IRE application was feasible at 300 and 650 V for the single and double contact setup in both ex vivo and in vivo studies. Significant differences in calculated resistance between double contact and single contact settings were observed (ex-vivo p ˂ 0.0001, in-vivo p = 0.02; Mann-Whitney). A mild temperature increase of the surrounding liver parenchyma was noted with increasing voltage (0.9-5.9 °C for 300-1000 V). The extent of necrotic changes in experimental samples in vivo correlated with the measured electric current (r² = 0.39, p = 0.01). No complications were observed during or after the in-vivo procedure.

CONCLUSION

Endoluminal IRE using an expandable tubular catheter in simulated metal stent occlusion is feasible. The relationship of active catheter electrodes to stent ingrowth tissue can be estimated based on resistance values.

The combination of endoluminal radiofrequency ablation and metal stent implantation for the treatment of malignant biliary stenosis - Randomized study

PURPOSE

To analyse whether endobiliary radiofrequency ablation prior metal stent insertion in malignant biliary stenosis show improved survival or stent patency.

METHODS

76 patients with histologically proven malignant biliary stenosis have been enrolled in a prospective, randomized study. In control arm, 40 patients underwent self-expandable metal stent insertion. In experimental arm, the endoluminal ablation with a bipolar radiofrequency catheter was performed immediately before stent insertion. A subgroup analysis of cholangiocarcinoma was performed (22 vs 21 patients). The objective of the study was to determine the rate of complications, duration of the stent patency and the survival of patients (Kaplan-Meier analysis).

RESULTS

No major complications related to the stent insertion and the endoluminal ablation were found. The mean primary stent patency was 5.2 (95% CI 0.7-12.8) vs 4.8 months (95% CI 0.8-18.2) months (p = 0.79) in control and experimental group, respectively, in the subgroup analysis with cholangiocarcinoma 4.5 (95% CI 0.8-10.3) and 9.6 (95% CI 5.2-11.2) months (p = 0.029). The median survival since the insertion of the stent was 6.8 (95 %CI 3.0-10.6) vs 5.2 (95 %CI 2.4-7.9) months (p = 0.495) and since the initial drainage 9.8 (95 %CI 6.9-12.7) vs 9.1 (95 %CI 5.4-12.7) months (p = 0.720) in the control and experimental arm.

CONCLUSION

Endobiliary radiofrequency ablation prior metal stent insertion showed increased patency rate only in patients with cholangiocarcinoma, on the other hand, no improvement in survival was demonstrated in this randomized clinical study.

Endoscopic revision efficacy after clinically successful bilateral metal stenting for advanced malignant hilar obstruction

BACKGROUNDS AND AIM

Multiple insertions of self-expandable metal stents (SEMS) for advanced malignant hilar obstruction (MHO) are now considered to be an effective palliative method for adequate drainage of liver volume. However, the efficacy of endoscopic reintervention in technically and clinically successful bilateral SEMS is limited. This study investigated the endoscopic revision efficacy in patients who underwent bilateral SEMS in MHO.

METHODS

Primary endoscopic revision using plastic or metal stents or an alternative percutaneous approach followed by secondary endoscopic revision was performed in patients who underwent clinically successful deployment of bilateral SEMS. The primary outcome was a technical success. Secondary outcomes were clinical success, adverse events, and patency duration after reintervention.

RESULTS

A total of 55 patients (83.3%) out of 66 enrolled patients underwent reintervention: primary endoscopic reintervention (n = 47) and secondary endoscopic revision following percutaneous drainage (n = 8). Intended technical success rates of primary and secondary endoscopic reintervention were 93.6% (44/47) and 87.5% (7/8), respectively (P = 0.47). Clinical success rates were 72.3% and 50%, respectively (P = 0.23). Stent malfunction rate after reintervention was 48.9% (23/47) and 37.5% (3/8) (P = 0.70) during follow up, and median cumulative stent patency duration was 119 and 55 days, respectively (log-rank P = 0.68). Stent patent rate after reintervention was not different according to the time interval. In univariate and multivariate analysis for stent patency duration-related factors after reintervention, there were no meaningful factors.

CONCLUSION

Primary endoscopic reintervention for bilateral SEMS in MHO was feasible technically and clinically. However, there were no statistically meaningful factors for stent patency duration after reintervention.

Placement of Palliative Stent With Guidance of a Percutaneous Transhepatic Stent

The incidence of pancreatic cancer has increased and outcomes have been improving with a multidisciplinary treatment approach. Pancreatoduodenectomy is the surgical approach for pancreatic head tumors; however, postoperative cholestasis or cholangitis may require endoscopic or percutaneous intervention. Placement of a percutaneous transhepatic cholangiographic (PTC) drain is a safe approach; however, this requires routine maintenance. This case demonstrates placement of a palliative biliary stent by a rendezvous approach using an in situ PTC drain.

Biliary stenting for hilar malignant biliary obstruction

Although endoscopic intervention is the mainstay for palliation of malignant biliary obstruction, a percutaneous approach has been preferred, particularly in patients with advanced high-grade hilar malignant biliary obstruction, because of the technical difficulty and risk of complications. However, recently, primary endoscopic palliation using plastic or metal stents has had higher technical and clinical success with fewer adverse events than the percutaneous approach. Endoscopic interventions are being done more and more frequently because of advances in metal stents, accessories, and techniques. However, several concerns, such as optimal stent type, number, and deployment method, remain to be resolved. Therefore, we reviewed the literature in order to identify the optimal biliary stenting strategy for patients with hilar malignant biliary obstruction, focusing on stent type (plastic vs metal), number (unilateral [single] vs bilateral [multiple]), and deployment method (stent-in-stent vs stent-by-stent).

Management of occluded self-expanding biliary metal stents in malignant biliary disease

BACKGROUND

Occlusion of self-expanding metal stents (SEMS) in malignant biliary obstruction occurs in up to 40% of patients. This study aimed to compare the different techniques to resolve stent occlusion in our collective of patients.

METHODS

Patients with malignant biliary obstruction and occlusion of biliary metal stent at a tertiary referral endoscopic center were retrospectively identified between April 1, 1994 and May 31, 2014. The clinical records were further analyzed regarding the characteristics of patients, malignant strictures, SEMS, management strategies, stent patency, subsequent interventions, survival time and case charges.

RESULTS

A total of 108 patients with biliary metal stent occlusion were identified. Seventy-nine of these patients were eligible for further analysis. Favored management was plastic stent insertion in 73.4% patients. Second SEMS were inserted in 12.7% patients. Percutaneous transhepatic biliary drainage and mechanical cleansing were conducted in a minority of patients. Further analysis showed no statistically significant difference in median overall secondary stent patency (88 vs. 143 days, P = 0.069), median survival time (95 vs. 192 days, P = 0.116), median subsequent intervention rate (53.4% vs. 40.0%, P = 0.501) and median case charge (€5145 vs. €3473, P = 0.803) for the treatment with a second metal stent insertion compared to plastic stent insertion. In patients with survival time of more than three months, significantly more patients treated with plastic stents needed re-interventions than patients treated with second SEMS (93.3% vs. 57.1%, P = 0.037).

CONCLUSIONS

In malignant biliary strictures, both plastic and metal stent insertions are feasible strategies for the treatment of occluded SEMS. Our data suggest that in palliative biliary stenting, patients especially those with longer expected survival might benefit from second SEMS insertion. Careful patient selection is important to ensure a proper decision for either management strategy.

Management of acute cholangitis as a result of occlusion from a self-expandable metallic stent in patients with malignant distal and hilar biliary obstructions

Acute cholangitis as a result of common bile duct stones can be managed; however, cholangitis caused by occlusion with a biliary self-expandable metallic stent (SEMS) in patients with an unresectable malignant biliary obstruction has not been fully discussed. The acute cholangitis clinical guidelines (Tokyo Guidelines 2013) recommend following the same procedure as that used for cholangitis; however, the patient's condition, including performance status, tumor extension or staging, and prognosis must be considered. Most physicians manage cholangitis from a SEMS occlusion using a two-step procedure. They insert endoscopic drainage with a plastic stent or insert a nasobiliary drainage tube, which does not exacerbate sepsis. Addition or replacement of a biliary SEMS is required in many cases depending on the cause of the occlusion. Tumor ingrowth through the stent mesh is common in uncovered SEMS and requires placement of another stent in an in-stent method. However, covered SEMS tends to be occluded by sludge, so it must be replaced because of the bacterial biofilm that forms on the covering membrane. The location of the biliary stricture (hilar or distal) should also be considered. Strategies for managing cholangitis as a result of occlusion by a biliary SEMS remain controversial, so prospective clinical trials are needed.

Percutaneous endobiliary RFA combined with balloon-sweep for re-opening occluded metallic biliary stents

The aim of this report is to discuss the results of percutaneous endobiliary radiofrequency ablation (RFA) combined with balloon-sweep technique in restoring the patency of occluded self-expandable metallic stents (SEMS) secondary to tumor infiltration. A total of eight patients underwent endobiliary RFA for reopening of occluded SEMS at our institute. After endobiliary RFA, all patients showed restoration of stent patency. After a median follow-up of 6.5 months, four patients had succumbed to the underlying disease at 3, 4, 6, and 7 months. Two of these required reinterventions at 2 and 5 months. One patient died of sepsis and aspiration pneumonia at 3 months. Of the remaining three patients, two required re-intervention after 2 months, while the other remained asymptomatic. The mean duration of stent patency after the first session of RFA was 4 ± 2.1 months, which was comparable to the primary patency of these stents (4.2 months). Our experience suggests that endobiliary RFA with balloon sweep is a safe and useful technique for re-establishing the patency of occluded SEMS.

Endoscopic ultrasound-guided antegrade stenting in an occluded biliary self-expandable metal stent

Endoscopic ultrasound-guided biliary drainage (EUS-BD) is an attractive option for patients who cannot undergo conventional endoscopic retrograde cholangiopancreatography (ERCP) and do not want surgery or percutaneous drainage procedures. We present the use of EUS-antegrade (EUS-AG) insertion of a self-expandable metal stent (SEMS) in a patient with a common hepatic duct cholangiocarcinoma, as well as a huge gastric lipoma, after recurrent biliary obstruction of a prior SEMS inserted via ERCP in the same session as a duodenal stent insertion for gastric outlet obstruction.

Stenting in Malignant Biliary Obstruction

Decompression of the biliary system in patients with malignant biliary obstruction has been widely accepted and implemented as part of the care. Despite a wealth of literature, there remains a significant amount of uncertainty as to which approach would be most appropriate in different clinical settings. This review covers stenting of the biliary system in cases of resectable or palliative malignant biliary obstruction, potential candidates for biliary drainage, technical aspects of the procedure, as well as management of biliary stent dysfunction. Furthermore, periprocedural considerations including proper mapping of the location of obstruction and the use of antibiotics are addressed.

Intraductal Radiofrequency Ablation Followed by Locoregional Tumor Treatments for Treating Occluded Biliary Stents in Non-Resectable Malignant Biliary Obstruction: A Single-Institution Experience

Objectives

To determine the safety and feasibility of intraductal radiofrequency ablation (RFA) followed by locoregional tumor treatments in patients with non-resectable malignant biliary obstruction and stent re-occlusion.

Methods

Fourteen patients with malignant biliary obstruction and blocked metal stents were studied retrospectively. All had intraductal RFA followed by locoregional tumor treatments and were monitored clinically and radiologically. The practicality, safety, postoperative complications, jaundice remission, stent patency and survival time were analyzed.

Results

Combination treatment was successful for all patients. There were no severe complications during RFA or local treatments. All patients had stent patency restored, with a decline in serum bilirubin. Three patients had recurrent jaundice by 195, 237 and 357 days; two patients underwent repeat intraductal RFA; and one required an internal-external biliary drain. The average stent patency time was 234 days (range 187-544 days). With a median follow-up of 384 days (range 187-544 days), six patients were alive, while eight had died. There was no mortality at 30 days. The 3, 6, 12 and 18 month survival rates were 100%, 100%, 64.3% and 42.9%, respectively.

Conclusion

Intraductal RFA followed by locoregional tumor treatments for occluded metal stents is safe and practically feasible and potential increase stent patency and survival times.

Self-expandable metal stents versus plastic stents for malignant biliary obstruction: a meta-analysis

BACKGROUND

Malignant biliary obstruction frequently portends a poor prognosis. Palliative treatment with stenting is often required to alleviate symptoms and potentially prevent adverse events.

OBJECTIVES

The aims of our study were (1) to evaluate the clinical difference between self-expandable metal stents (SEMSs) and plastic stents (PSs) in both hilar and distal malignant biliary obstruction on occlusion rate and 30-day mortality rate (primary outcomes) and stent insertion success rate, therapeutic failure, reintervention rate, and adverse events (secondary outcomes); (2) to compare unilateral stenting with bilateral stenting in hilar malignant obstruction in terms of occlusion rate and 30-day mortality rate (primary outcomes) and insertion success rate, therapeutic failure, and adverse events (secondary outcomes).

METHODS

PubMed, Embase, and Cochrane databases were searched for studies that provided data about malignant biliary obstruction and stent therapy. We included randomized, controlled trials (RCT), prospective observational cohort, and retrospective case-control studies. The quality of each included RCT study was assessed by the Jadad scale. Mantel-Haenszel odds ratios (ORs) and mean differences were calculated by using a random-effects model.

RESULTS

Nineteen studies involving 1989 patients (1045 SEMSs and 944 PSs) were included for the comparison of SEMSs and PSs. We also included 7 studies that compared unilateral with bilateral stenting involving 634 patients (346 unilateral and 268 bilateral). Our meta-analysis confirmed that SEMSs are associated with a statistically significant lower risk of occlusion compared with PSs in the short term (OR 0.27; 95% confidence interval [CI], 0.13-0.60) and long term (OR 0.38; 95% CI, 0.28-0.53). SEMSs had a lower 30-day occlusion rate than PSs in both hilar malignant obstruction (OR 0.16; 95% CI, 0.04-0.62) and distal malignant obstruction (OR 0.36; 95% CI, 0.14-0.93). SEMSs had a lower long-term occlusion rate compared with PSs in hilar malignant obstruction (OR 0.28; 95% CI, 0.19-0.39) and distal malignant obstruction (OR 0.42; 95% CI, 0.27-0.64). The 30-day mortality rate was similar with SEMSs and PSs (OR 0.74; 95% CI, 0.47-1.17). Therapeutic failure was more likely when using PSs (13%) compared with SEMSs (7%) (OR 0.43; 95% CI, 0.27-0.67). SEMSs required fewer reinterventions compared with PSs (mean difference, -0.49; 95% CI, -0.8 to -0.19). The incidence of cholangitis was statistically lower with SEMSs (8% vs 21%) (OR 0.41; 95% CI, 0.22-0.76). Bilateral stenting for hilar obstruction was not associated with a lower obstruction rate than unilateral stenting (OR 1.49; 95% CI, 0.77-2.89) or a lower 30-day mortality rate (OR 0.73; 95% CI, 0.29-1.79). There was no statistical difference in therapeutic failure (OR 1.47; 95% CI, 0.77-2.89) or cholangitis incidence (OR 0.61; 95% CI, 0.27-1.38).

CONCLUSION

SEMSs are associated with a statistically significantly lower occlusion rate, less therapeutic failure, less need for reintervention, and lower cholangitis incidence. There was no statistically significant difference in occlusion rate, therapeutic failure, and cholangitis incidence with bilateral stenting. Guideline recommendations may need to be modified to reflect clear and compelling data demonstrating the benefit of SEMSs in patients with malignant biliary obstruction. Bilateral stenting should be avoided because it has no benefit over unilateral stenting in terms of occlusion rate or therapeutic failure.

Endoscopic bilio-duodenal bypass: outcomes of primary and revision efficacy of combined metallic stents in malignant duodenal and biliary obstructions

BACKGROUND

Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients' lives, as well as the need for and efficacy of endoscopic revision, are unclear.

AIM

This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients' lives and the need for endoscopic revision.

METHODS

This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients' death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency.

RESULTS

Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43-198.98; P = 0.025).

CONCLUSIONS

Endoscopic bilio-duodenal bypass is clinically effective, and the majority of the patients need no additional intervention until their death. Endoscopic revision is feasible and has a high success rate.

Effect of external beam radiotherapy on patency of uncovered metallic stents in patients with inoperable bile duct cancer

BACKGROUND

Although biliary decompression with metallic stenting is the preferred treatment for inoperable bile duct cancer (BDC), maintenance of patency is still unsatisfactory. We tried to assess the effectiveness and safety of external beam radiotherapy (EBRT) for prolonging stent patency in patients having uncovered metallic stents.

METHOD

We retrospectively reviewed 50 patients who received endoscopic stenting, of whom 18 received EBRT (RT group) and 32 did not (non-RT group).

RESULTS

No difference was found in baseline characteristics between the two groups. Although stent patency was longer in the RT group than that in the non-RT group (140.7+/-51.3 vs 136.4+/-34.9 days, P=0.94), the difference was not statistically significant. There were a lower rate of stent occlusion (27.8% vs 50.0% of patients, P=0.12) and a longer overall survival (420.1+/-73.2 vs 269.1+/-41.7 days, P=0.11) in the RT group than in the non-RT group, and the difference again was not statistically significant. The development of adverse reactions did not differ (55.6% vs 53.1% of patients, P=0.91). There was no serious adverse reaction in both groups (P=0.99).

CONCLUSIONS

EBRT did not significantly improve stent patency in patients with inoperable BDC having uncovered metallic stents. However, EBRT was safe. Future trials with refined protocols for better efficacy are expected.

Current status and issues regarding biliary stenting in unresectable biliary obstruction

In the present review, we describe the current status of biliary stenting in patients with unresectable malignant biliary strictures. Self-expandable metallic stents (SEMS) are the ideal biliary stent for both distal and hilar biliary strictures, although in terms of distal biliary strictures, there is still some debate as to the selection of covered or uncovered SEMS, suprapapillary or transpapillary stent placement, side-by-side or stent-in-stent placement, unilateral or bilateral stent placement and the necessity for sphincterotomy. Further high-quality randomized controlled trials for these procedures are warranted.