Randomised trial of self-expanding metal stents versus polyethylene stents for distal malignant biliary obstruction

Endoscopic stenting in bile duct cancer increases liver volume

BACKGROUND

Objective evaluation tools for assessing the effectiveness of stenting in palliative treatment of malignant biliary obstruction are not satisfactory. Effects of biliary stenting on liver volume change have never been studied.

OBJECTIVE

We aimed to use volumetry to analyze liver volume changes after endoscopic stenting in bile duct cancer according to the location and number of stents.

DESIGN

Retrospective review.

SETTING

University hospital.

PATIENTS

Patients with a diagnosis of hilar or distal bile duct cancer and who underwent biliary metal stenting.

INTERVENTIONS

ERCP with self-expandable metal stent placement.

MAIN OUTCOME MEASUREMENTS

Liver volume change after biliary stenting and its comparison according to the location (hilar vs distal common bile duct) and number (hilar bilateral vs hilar unilateral).

RESULTS

There were 60 patients; 31 were treated for hilar bile duct cancer (13 for bilateral stent and 18 for unilateral stent) and 29 for distal bile duct cancer. Overall mean follow-up duration was 11.7 ± 4.9 weeks. Liver volume increased 17.4 ± 24.1%. The rate of liver growth was rapid during the early period from 4 to 8 weeks. Stenting in hilar bile duct cancer tended to increase liver volume more than distal biliary stents (22.5% vs 11.9%, P = .091). In hilar bile duct cancer, unilateral and bilateral stents showed similar liver volume increases (20.1% and 25.8%, respectively; P = .512).

LIMITATIONS

Single center, retrospective.

CONCLUSIONS

Biliary stenting markedly increased liver volume in both hilar and distal bile duct cancer. Our data suggest that liver volume assessment could be a useful tool for evaluating stent efficacy.

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.

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

BACKGROUND

Self-expandable metal stents (SEMS) are widely utilized to relieve symptoms of malignant gastric outlet obstruction (GOO), but GOO is frequently complicated by nonresectable distal biliary obstruction. The optimal endoscopic approach to biliary drainage in this setting remains controversial and has yet to be resolved.

AIMS

To compare the safety and efficacy of endoscopic ultrasound-guided transmural biliary drainage (EUS-BD) and transpapillary drainage in patients with an indwelling duodenal SEMS.

METHODS

Patients who underwent EUS-BD or transpapillary drainage for distal malignant biliary obstruction with an indwelling duodenal SEMS between June 2007 and August 2012 at three Japanese tertiary referral centers were identified retrospectively. We compared times to stent dysfunction, causes of dysfunction, and procedural related complications between these two groups.

RESULTS

Twenty patients were included in the study (7 EUS-BD and 13 transpapillary drainage). EUS-BD was performed via hepaticogastrostomy using a SEMS in three patients and via choledochoduodenostomy using a SEMS or a plastic stent in two patients each. Transpapillary drainage was performed using a SEMS in all patients. The stent patency rate in the EUS-BD group was higher than that in the transpapillary drainage group (100 vs. 71% at 1 month and 83 vs. 29% at 3 months, respectively). The rate of stent dysfunction in the EUS-BD group tended to be lower than that in the transpapillary group (14 vs. 54%; P = 0.157). Complication rates were similar between the groups (P = 1.000), with moderate bleeding in one patient in the EUS-BD group and mild pancreatitis in one patient in the transpapillary group.

CONCLUSION

Endoscopic ultrasound-guided transmural biliary drainage is an alternative to transpapillary drainage in patients with an indwelling duodenal SEMS.

Comparison of the efficacy of covered versus uncovered metallic stents in treating inoperable malignant common bile duct obstruction: a randomized trial

PURPOSE

To compare patency and overall survival achieved with covered versus uncovered metallic stents among patients with inoperable malignant extrahepatic biliary obstruction.

MATERIALS AND METHODS

There were 40 patients enrolled in this prospective randomized study between January 2012 and July 2013. Mean age of patients was 62.6 years (range, 43-86 y). The malignancies causing extrahepatic biliary obstruction were pancreatic cancer (n = 18), stomach cancer (n = 13), gallbladder cancer (n = 3), common bile duct cancer (n = 2), and other cancer types (n = 4). Uncovered (n = 20) and covered (n = 20) stents were used. Stent patency, overall survival, and complications were evaluated and statistically compared.

RESULTS

Mean patency of uncovered stents (413.3 d ± 63.0) was significantly longer than mean patency of covered ones (207.5 d ± 46.0; P = .041). Mean overall survival was 359.9 days ± 61.5 for uncovered stents, which was statistically similar to survival of 350.5 days ± 43.8 for covered stents (P = .271). Causes of recurrent obstruction included tumor ingrowth (n = 2), tumor overgrowth (n = 5), debris or food material (n = 5), and stent migration (n = 2). One case of acute cholecystitis occurred in covered stent group.

CONCLUSIONS

Uncovered metallic stents had superior patency duration than covered stents for patients with malignant extrahepatic biliary obstruction. However, the overall complication and survival rates achieved with covered and uncovered stents were similar.

Photodynamic therapy in cholangiocarcinoma: an overview

Cholangiocarcinoma is a challenge to manage; mortality rate is nearly as high as the incidence. Unless curative resection is performed, these tumours are rapidly fatal because they respond poorly to current therapies. Symptoms occur late in cholangiocarcinoma and curative resection can be performed in less than half of the patients. In non-resectable disease, endoprostheses insertion can relieve jaundice and improve quality of life, provided that tumour extension does not lead to diffuse intrahepatic stenoses of ductal system. However, tumour growth cannot be influenced and therefore, prognosis remains dismal. Despite the fact, that radiotherapy and chemotherapy could reduce tumour volume and growth, no survival advantage has yet been shown. Photodynamic therapy has been evaluated as an new additional, palliative option. A randomised trial comparing photodynamic therapy plus endoprostheses insertion versus endoprostheses insertion alone, indicates a considerably benefit on survival time, cholestasis and quality of life in large, advanced cholangiocarcinoma. Furthermore, few specific side effects occurred. Since photodynamic therapy is the first approach leading to an improvement of prognosis, it should be offered to patients with non-resectable cholangiocarcinoma.

Percutaneous use of ePTFE/FEP-covered metallic stent for palliation of malignant biliary obstruction

INTRODUCTION

Placement of self-expanding metallic stents has been a standard palliative treatment for patients with inoperable biliary malignancy, aiming at improving quality of life via a minimally invasive procedure. This study aimed to evaluate the efficacy of percutaneous placement of expanded polytetrafluoroethylene/fluorinated ethylene propylene-covered metallic stents for palliation of inoperable biliary malignancy.

MATERIAL AND METHODS

Between February 2012 and April 2013, 11 patients with inoperable malignant biliary obstruction were treated with stent implantation. Serum bilirubin and liver enzyme levels were measured before/immediately after stent placement and at one, three, and six months. Patient survival and stent patency were calculated using Kaplan-Meier analysis.

RESULTS

No migration occurred. Patients showed clinical improvement immediately and one month after stent placement, with a significant reduction in mean serum bilirubin level (p < 0.05). At six months, bilirubin levels were <1.5 mg/dL in all cases. One patient developed acute liver failure four days after stent implantation, leading to death. Survival rates were 90% at three months and 70% at six months. Primary patency rates were 100%, 100%, and 90% at one, three, and six months, respectively.

CONCLUSION

Percutaneous placement of expanded polytetrafluoroethylene/fluorinated ethylene propylene-covered metallic stents offered an effective palliative therapy for patients with inoperable biliary malignancy.

Metallic stent with high axial force as a risk factor for cholecystitis in distal malignant biliary obstruction

BACKGROUND AND AIM

Tumor involvement to the orifice of cystic duct (OCD) is a risk factor for cholecystitis after self-expandable metallic stent (SEMS) placement, but its prevention is still difficult. We conducted this multicenter analysis to clarify a type of SEMS or a method to place SEMS which would decrease the incidence of cholecystitis after SEMS placement.

METHODS

The incidence of cholecystitis was studied in consecutive patients receiving SEMS for distal malignant biliary obstruction in five tertiary care centers. Multiple logistic regression analysis was performed to evaluate risk factors for cholecystitis.

RESULTS

A total of 376 patients who received SEMS placement for distal malignant biliary obstruction were analyzed. Tumor involvement to OCD was diagnosed in 25.3%. Overall incidence of cholecystitis was 6.9%. Cholecystitis was observed in 8.0% of 300 patients with covered SEMS, 16.8% of 95 patients with tumor involvement to OCD, 10.8% of 234 patients with SEMS of high axial force (AF), and 12.0% of 158 patients with SEMS length ≤ 60 mm. In the multivariate analysis, tumor involvement to OCD (odds ratio [OR] 5.40, P < 0.001), SEMSs with high AF (OR 5.33, P = 0.002), and SEMS length ≤ 60 mm (OR 3.19, P = 0.010) are risk factors. Among patients with tumor involvement to OCD, the incidence of cholecystitis in SEMS with high and low AF was 25.0% and 5.0%, respectively.

CONCLUSION

This study with an expanded cohort reconfirmed tumor involvement to OCD as a risk factor for cholecystitis after SEMS placement. SEMS with low AF might decrease cholecystitis.

How are palliative care cancer populations characterized in randomized controlled trials? A literature review

CONTEXT

The difficulties in defining a palliative care patient accentuate the need to provide stringent descriptions of the patient population in palliative care research.

OBJECTIVES

To conduct a systematic literature review with the aim of identifying which key variables have been used to describe adult palliative care cancer populations in randomized controlled trials (RCTs).

METHODS

The data sources used were MEDLINE (1950 to January 25, 2010) and Embase (1980 to January 25, 2010), limited to RCTs in adult cancer patients with incurable disease. Forty-three variables were systematically extracted from the eligible articles.

RESULTS

The review includes 336 articles reporting RCTs in palliative care cancer patients. Age (98%), gender (90%), cancer diagnosis (89%), performance status (45%), and survival (45%) were the most frequently reported variables. A large number of other variables were much less frequently reported.

CONCLUSION

A substantial variation exists in how palliative care cancer populations are described in RCTs. Few variables are consistently registered and reported. There is a clear need to standardize the reporting. The results from this work will serve as the basis for an international Delphi process with the aim of reaching consensus on a minimum set of descriptors to characterize a palliative care cancer population.

Investigation and management of pancreatic tumours

Pancreatic cancer is the 10th most commonly diagnosed cancer in the UK and the fifth most common cause of cancer death. It remains one of the most aggressive cancers with over 95% of patients affected dying of their disease. Often presenting at an advanced stage of disease progression, there is currently no simple screening test available. Therefore a high clinical suspicion and prompt appropriate investigation is required from physicians when dealing with patients with symptoms in keeping with pancreatic cancer. The gastroenterology 2010 curriculum states that trainees should learn the presentation and multidisciplinary management of patients with pancreatic tumours. In this article we discuss the typical clinical presentations of common and less common pancreatic tumours followed by the investigation, staging and management required.

Treatment of borderline resectable pancreatic cancer

OPINION STATEMENT

Borderline resectable pancreatic adenocarcinoma represents a subset of localized cancers that are at high risk for a margin-positive resection and early treatment failure when resected de novo. Although several different anatomic definitions for this disease stage exist, there is agreement that some degree of reconstructible mesenteric vessel involvement by the tumor is the critical anatomic feature that positions borderline resectable between anatomically resectable and unresectable (locally advanced) tumors in the spectrum of localized disease. Consensus also exists that such cancers should be treated with neoadjuvant chemotherapy and/or chemoradiation before resection; although the optimal algorithm is unknown, systemic chemotherapy followed by chemoradiation is a rational approach. Although gemcitabine-based systemic chemotherapy with either 5-FU or gemcitabine-based chemoradiation regimens has been used to date, newer regimens, including FOLFIRINOX, should be evaluated on protocol. Delivery of neoadjuvant therapy necessitates durable biliary decompression for as many as 6 months in many patients with cancers of the pancreatic head. Patients with no evidence of metastatic disease following neoadjuvant therapy should be brought to the operating room for pancreatectomy, at which time resection of the superior mesenteric/portal vein and/or hepatic artery should be performed when necessary to achieve a margin-negative resection. Following completion of multimodality therapy, patients with borderline resectable pancreatic cancer can expect a duration of survival as favorable as that of patients who initially present with resectable tumors. Coordination among a multidisciplinary team of physicians is necessary to maximize these complex patients' short- and long-term oncologic outcomes.

The current status of preoperative biliary drainage for patients who receive pancreaticoduodenectomy for periampullary carcinoma: a comprehensive review

BACKGROUND

Surgery on patients with malignant obstructive jaundice carries increased risks of postoperative morbidity and mortality. Preoperative biliary drainage has been developed to reduce this procedure-related risks, but its role in patients who are going to receive pancreaticoduodenectomy for periampullary carcinoma is still controversial.

METHODS

This article aimed at reviewing the current status of preoperative biliary drainage for patients with peri-ampullary tumors who were candidates for pancreaticoduodenectomy. A MEDLINE and PubMed database search from 1980 to 2013 was performed to identify relevant articles using the keywords "pancreaticoduodenectomy", "preoperative biliary drainage", "jaundice", "peri-ampullary neoplasm" and "carcinoma of pancreas". Additional papers were identified by a manual search of the references from the key articles.

RESULTS

There were six randomized controlled trials (RCTs) and 5 meta-analyses on preoperative biliary drainage for patients with malignant obstructive jaundice. Most of the results of these studies could not be used to define the role of preoperative biliary drainage for patients who received pancreaticoduodenectomy for periampullary carcinoma because: first, the majority of these studies were on bypass or palliative resections; second, various pathologies with both proximal and distal biliary obstruction were included; third, there were different forms of percutaneous or endoscopic drainage procedures; fourth, there were different durations of preoperative drainage; and finally, there were variations in the definition of events and outcomes. There was only one RCT which included a homogeneous group of patients with carcinoma of pancreas who underwent pancreaticoduodenectomy. For patients with periampullary tumor, the RCTS and meta-analyses showed no benefit of preoperative biliary drainage. Instead, there were some concerns about the drainage-related complications and the increase in positive intraoperative bile culture rate and the associated infective complication rate postoperatively.

CONCLUSION

Routine preoperative biliary drainage showed no beneficial effect on the surgical outcome for patients with periampullary tumor. A selective approach of preoperative biliary drainage should be adopted for these patients. The optimal duration and modality of preoperative biliary drainage remain unclear.

Novel antireflux covered metal stent for recurrent occlusion of biliary metal stents: a pilot study

BACKGROUND

Feasibility of antireflux metal stent (ARMS), designed to prevent duodenobiliary reflux, was reported in patients with distal malignant biliary obstruction. In this prospective pilot study, we aimed to evaluate a newly designed ARMS as a reintervention for self-expandable metallic stent (SEMS) occlusion believed to be caused by duodenobiliary reflux.

PATIENTS AND METHODS

Patients with non-resectable distal malignant biliary obstruction were included in whom a prior SEMS was occluded as a result of sludge or food impaction between March 2010 and January 2012 at two Japanese tertiary referral centers. The occluded SEMS were endoscopically removed, if possible, and subsequently replaced by a newly designed ARMS. We evaluated the technical success rate and complications of ARMS and compared the time to occlusion of ARMS with that of prior SEMS.

RESULTS

A total of 13 patients were included. ARMS was successfully placed in all patients in a single procedure. No procedure-related complications were identified. ARMS occlusion occurred in two patients (15%), the causes of which were sludge in one patient and unknown in the other. ARMS migration occurred in four patients (31%). ARMS patency time was significantly longer than that of prior SEMS (median, not available vs 58 days; P = 0.039).

CONCLUSIONS

This newly designed ARMS is a technically feasible, safe, and effective reintervention for SEMS occlusion as a result of sludge or food impaction. An anti-migration mechanism to improve the outcomes of ARMS should be considered.

Estimation and comparison of cumulative incidences of biliary self-expandable metallic stent dysfunction accounting for competing risks

BACKGROUND

Self-expandable metallic stent (SEMS) placement is widely carried out for distal malignant biliary obstruction, and survival analysis is used to evaluate the cumulative incidences of SEMS dysfunction (e.g. the Kaplan-Meier [KM] method and the log-rank test). However, these statistical methods might be inappropriate in the presence of 'competing risks' (here, death without SEMS dysfunction), which affects the probability of experiencing the event of interest (SEMS dysfunction); that is, SEMS dysfunction can no longer be observed after death. A competing risk analysis has rarely been done in studies on SEMS.

PATIENTS AND METHODS

We introduced the concept of a competing risk analysis and illustrated its impact on the evaluation of SEMS outcomes using hypothetical and actual data. Our illustrative study included 476 consecutive patients who underwent SEMS placement for unresectable distal malignant biliary obstruction.

RESULTS

A significant difference between cumulative incidences of SEMS dysfunction in male and female patients via theKM method (P = 0.044 by the log-rank test) disappeared after applying a competing risk analysis (P = 0.115 by Gray's test). In contrast, although cumulative incidences of SEMS dysfunction via the KM method were similar with and without chemotherapy (P = 0.647 by the log-rank test), cumulative incidence of SEMS dysfunction in the non-chemotherapy group was shown to be significantly lower (P = 0.031 by Gray's test) in a competing risk analysis.

CONCLUSION

Death as a competing risk event needs to be appropriately considered in estimating a cumulative incidence of SEMS dysfunction, otherwise analytical results may be biased.

Cholangiocarcinoma: Biology, Clinical Management, and Pharmacological Perspectives

Cholangiocarcinoma (CCA), or tumor of the biliary tree, is a rare and heterogeneous group of malignancies associated with a very poor prognosis. Depending on their localization along the biliary tree, CCAs are classified as intrahepatic, perihilar, and distal, and these subtypes are now considered different entities that differ in tumor biology, the staging system, management, and prognosis. When diagnosed, an evaluation by a multidisciplinary team is essential; the team must decide on the best therapeutic option. Surgical resection of tumors with negative margins is the best option for all subtypes of CCA, although this is only achieved in less than 50% of cases. Five-year survival rates have increased in the recent past owing to improvements in imaging techniques, which permits resectability to be predicted more accurately, and in surgery. Chemotherapy and radiotherapy are relatively ineffective in treating nonoperable tumors and the resistance of CCA to these therapies is a major problem. Although the combination of gemcitabine plus platinum derivatives is the pharmacological treatment most widely used, to date there is no standard chemotherapy, and new combinations with targeted drugs are currently being tested in ongoing clinical trials. This review summarizes the biology, clinical management, and pharmacological perspectives of these complex tumors.

Endoscopic treatment options for cholangiocarcinomas

Cholangiocellular carcinoma (CCC) is a very aggressive tumor, which remains highly resistant to current chemoradiation therapies. Death is usually caused by the tumor burden. However, biliary obstruction, which leads to cholangitis and liver failure, is also a cause of death. Therefore, relief of biliary obstruction is one of the key palliative treatment options for patients with hilar or distal CCC. Radiologic or endoscopic insertions of stents (plastic or self-expanding metal) are definite biliary drainage options. Whereas stents alone can help achieve relief of bile duct obstruction, endoscopic ablative interventions with photodynamic therapy or radiofrequency ablation are also useful in destroying intraluminal tumor. Destroying the tumor leads to an increase in the luminal diameter of the obstructed bile duct, allowing for placement of more or larger diameter stents, and thus improving bile flow. Besides decreasing morbidity associated with obstruction, ablative therapies such as photodynamic therapy have also been associated with improved survival in a sub-group of patients with CCC and should therefore be incorporated into the treatment algorithm of any center treating patients with CCC.

Risk factors for proximal migration of biliary tube stents

AIM: To analyze the risk factors for biliary stent migration in patients with benign and malignant strictures.

METHODS: Endoscopic stent placement was performed in 396 patients with bile duct stenosis, at our institution, between June 2003 and March 2009. The indications for bile duct stent implantation included common bile duct stone in 190 patients, malignant lesions in 112, chronic pancreatitis in 62, autoimmune pancreatitis in 14, trauma in eight, surgical complications in six, and primary sclerosing cholangitis (PSC) in four. We retrospectively examined the frequency of stent migration, and analyzed the patient factors (disease, whether endoscopic sphincterotomy was performed, location of bile duct stenosis and diameter of the bile duct) and stent characteristics (duration of stent placement, stent type, diameter and length). Moreover, we investigated retrieval methods for migrated stents and their associated success rates.

RESULTS: The frequency of tube stent migration in the total patient population was 3.5%. The cases in which tube stent migration occurred included those with common bile duct stones (3/190; 1.6%), malignant lesions (2/112; 1.8%), chronic pancreatitis (4/62; 6.5%), autoimmune pancreatitis (2/14; 14.3%), trauma (1/8; 12.5%), surgical complications (2/6; 33.3%), and PSC (0/4; 0%). The potential risk factors for migration included bile duct stenosis secondary to benign disease such as chronic pancreatitis and autoimmune pancreatitis (P = 0.030); stenosis of the lower bile duct (P = 0.031); bile duct diameter > 10 mm (P = 0.023); duration of stent placement > 1 mo (P = 0.007); use of straight-type stents (P < 0.001); and 10-Fr sized stents (P < 0.001). Retrieval of the migrated stents was successful in all cases. The grasping technique, using a basket or snare, was effective for pig-tailed or thin and straight stents, whereas the guidewire cannulation technique was effective for thick and straight stents.

CONCLUSION: Migration of tube stents within the bile duct is rare but possible, and it is important to determine the risk factors involved in stent migration.

In vivo and in situ evaluation of a wireless magnetoelastic sensor array for plastic biliary stent monitoring

This paper presents the in vivo and in situ evaluation of a system that wirelessly monitors the accumulation of biliary sludge in a plastic biliary stent. The sensing element, located within the stent, is a passive array of magnetoelastic resonators that is queried by a wireless electromagnetic signal. The in vivo and in situ testing uses commercially-available plastic biliary stents, each enhanced with an array of ribbon sensors (formed from Metglas™ 2826 MB). The sensor array is approximately 70 mm long and contains individual resonators that are 1 mm in width and have lengths of 10 mm, 14 mm, and 20 mm. The array is anchored into the 2.8 mm inner-diameter stent using a thermal staking technique. For the in situ testing, an instrumented stent is placed in various locations within the abdominal cavity of a female domestic swine carcass to evaluate the wireless range of the system; these results show that a wireless signal can be obtained from a range of at least 7.5 cm from a sensor array covered in bile. The in vivo testing includes the endoscopic implantation of an instrumented stent into the bile duct of a swine. After implantation, the swine was housed for a period of 4 weeks, during which the animal showed no ill effects and followed the expected growth curve from 29 kg to 42 kg. At the conclusion of the in vivo test, the animal was euthanized, and the instrumented stent explanted and examined. The results presented in this paper indicate that the monitoring system does not adversely affect the health of the animal and can feasibly provide sufficient wireless range after implantation.

Metal versus plastic stents for malignant biliary obstruction: an update meta-analysis

BACKGROUND AND OBJECTIVE

The data on comparisons of stent patency, re-intervention rate and patient survival between metal and plastic stents in palliation of malignant biliary obstruction have never been pooled. We carry out a meta-analysis to summarise current evidence for clinical efficacy of metal and plastic stents in the treatment of malignant biliary obstruction.

METHODS

A comprehensive search of several databases was conducted. A fixed-effects or random-effects model was used to pool data of all study endpoints. Sensitivity analysis and subgroup analysis (distal vs. hilar biliary obstruction) were also performed.

RESULTS

Ten randomized clinical trials were identified. Compared with plastic stents, metal stents were associated with a significantly longer stent patency (HR=0.36; 95% CI: 0.28-0.47; I(2)=0%), fewer numbers of re-intervention (WMD=0.59; 95% CI: 0.28-0.90; I(2)=76.4%) and longer patient survival (HR=0.74; 95% CI: 0.64-0.85; I(2)=16.0%). These results were still significant by sensitivity analysis. All outcomes reached statistical significance except of the pooled WMD of number of re-intervention in the studies with hilar biliary obstruction. No publication bias was observed.

CONCLUSIONS

Metal stents were associated with a significantly longer stent patency, lower re-intervention rate and longer patient survival in palliation of malignant biliary obstruction when compared to plastic stents.

Management of dysfunctional covered self-expandable metallic stents in patients with malignant distal biliary obstruction

BACKGROUND

Endoscopic placement of covered self-expandable metallic stents (CSEMSs) is effective for distal malignant biliary obstruction. However, management of dysfunctional CSEMSs has not been established.

METHODS

Between March 1998 and July 2007, a total of 74 patients who underwent endoscopic re-interventions for CSEMS dysfunction were analyzed. Second stent insertion (CSEMS or plastic stent) or mechanical cleaning of the occluded CSEMS was performed endoscopically. The period between second stent insertion and stent dysfunction or patient death (time to dysfunction; TTD) was calculated. The cleaned initial CSEMSs were analyzed as second stents.

RESULTS

Dysfunction of the second stent occurred in 17 of 37 patients (45.9%) in the CSEMS group, 16 of 20 (80.0%) in the plastic stent group, and 13 of 17 (76.5%) in the cleaning group. The median TTD of each group was 176, 57, and 46 days, respectively. The cumulative TTD was significantly higher in the CSEMS group than in the plastic stent and cleaning groups (P = 0.08). From the multivariate analysis, sludge occlusion of the first CSEMS was identified as a significant risk factor for second stent dysfunction (HR, 2.51; 95% CI, 1.19-5.46), and placement of the second CSEMS significantly reduced the risk of dysfunction (HR, 0.39; 95% CI, 0.18-0.79).

CONCLUSIONS

Insertion of a new CSEMS should be considered as the treatment of choice for the management of dysfunctional CSEMSs.

Covered self-expandable metal stents with an anti-migration system improve patency duration without increased complications compared with uncovered stents for distal biliary obstruction caused by pancreatic carcinoma: a randomized multicenter trial

OBJECTIVES

The requirements of biliary stents used in the palliation of malignant biliary obstruction are a long duration of patency and minimal adverse effects. Covered self-expandable metal stents (SEMSs) have been shown to prevent tumor ingrowth, which is the most frequent complication of uncovered SEMSs. However, because they are prone to migration, the superiority of covered SEMS has yet to be convincingly demonstrated. The aim of this study was to evaluate the superiority of covered over uncovered SEMSs in the palliation of distal biliary obstruction due to unresectable pancreatic carcinoma, using both stent types with relatively low axial force and uncovered flared ends to prevent their migration.

METHODS

From April 2009 to December 2010, 120 patients who were admitted to 22 tertiary-care centers because of distal biliary obstruction from unresectable pancreatic carcinomas were enrolled in this prospective randomized multicenter study. Patients were randomly assigned to receive a covered or uncovered SEMS deployed at the site of the biliary stricture during endoscopic retrograde cholangiopancreatography. Stent patency time, patient survival time, patient survival time without stent dysfunction (time to stent dysfunction or patient death), cause of stent dysfunction (ingrowth, overgrowth, migration, or sludge formation), and serious adverse events were compared between covered and uncovered SEMS groups.

RESULTS

Patient survival time in the two groups did not significantly differ (median: 285 and 223 days, respectively; P=0.68). Patient survival time without stent dysfunction was significantly longer in the covered than in the uncovered SEMS group (median: 187 vs. 132 days; P=0.043). Stent patency was also significantly longer in the covered than in the uncovered SEMS group (mean±s.d.: 219.3±159.1 vs. 166.9±124.9 days; P=0.047). Reintervention for stent dysfunction was performed in 14 of 60 patients with covered SEMSs (23%) and in 22 of 60 patients with uncovered SEMSs (37%; P=0.08). Stent dysfunction was caused by tumor ingrowth, tumor overgrowth, and sludge formation in 0 (0%), 3 (5%), and 11 (18%) patients in the covered SEMSs group, and in 15 (25%), 2 (3%), and 6 (10%) patients in the uncovered SEMSs group, respectively. Stent migration was not observed in either group. Rates of tumor overgrowth and sludge formation did not significantly differ between the two groups, whereas the rate of tumor ingrowth was significantly lower in the covered than in the uncovered SEMS group (P<0.01). Acute pancreatitis occurred in only one patient in the covered SEMS group. Acute cholecystitis occurred in one patient in the covered SEMS group and in two patients in the uncovered SEMS group. There was no significant difference between the two groups in the incidence of serious adverse events.

CONCLUSIONS

By preventing tumor ingrowth and migration, covered SEMSs with an anti-migration system had a longer duration of patency than uncovered SEMSs, which recommends their use in the palliative treatment of patients with biliary obstruction due to pancreatic carcinomas.

Impact of anticancer treatment on recurrent obstruction in covered metallic stents for malignant biliary obstruction

BACKGROUND

In patients with unresectable malignant biliary obstruction (MBO), anticancer treatment is often administered. The impact of anticancer treatment on recurrent biliary obstruction in covered self-expandable metallic stents (SEMS) has not been fully elucidated.

METHODS

Data on 279 patients enrolled in a multicenter prospective cohort study of two different covered SEMS for distal MBO, WATCH study (141 partially covered WallFlex stents and 138 partially covered Wallstents) were retrospectively analyzed. The rates and causes of recurrent biliary obstruction (stent occlusion or migration) were compared between anticancer treatment group (n = 173) and best supportive care alone (BSC) group (n = 106). Cumulative time and prognostic factors for recurrent biliary obstruction were analyzed, using a proportional hazards model with death without recurrent biliary obstruction as a competing risk.

RESULTS

The overall rate (43 vs. 25%, P = 0.002) and the cumulative incidence (16.1 vs. 8.2, 27.9 vs. 18.9 and 44.1 vs. 26.6% at 3, 6 and 12 months, P = 0.030 by Gray's test) of recurrent biliary obstruction were significantly higher in anticancer treatment group compared with BSC group. The multivariate analysis revealed anticancer treatment [subdistribution hazard ratio (SHR) 1.93, P = 0.007) as well as the use of a partially covered WallFlex stent (SHR 0.65, P = 0.049) as prognostic factors.

CONCLUSIONS

Anticancer treatment was a risk factor for recurrent biliary obstruction in covered SEMS for distal MBO. The superiority of a partially covered WallFlex stent was again confirmed in this competing risk analysis; UMIN-CTR: UMIN000002293.

Efficacy of plastic stent placement inside bile ducts for the treatment of unresectable malignant hilar obstruction (with videos)

BACKGROUND

Recent reports have addressed the utility of plastic stent (PS) placement inside bile ducts for treating biliary obstructions. Here, we evaluated the utility and safety of PS placement inside bile ducts for treating unresectable malignant hilar biliary obstruction.

METHODS

We conducted a retrospective study of 27 patients with unresectable malignant hilar biliary obstruction who underwent intraductal modified PS placement. We modified the PS, by cutting off the distal end to facilitate insertion through the papilla of Vater, and attached a nylon thread to the distal end for removal. We evaluated complications, the time to recurrent biliary obstruction (TRBO), and removability.

RESULTS

Bilateral stenting was performed in nine of the 27 patients. Mild acute pancreatitis occurred in one patient (4%). Recurrent biliary obstruction (RBO) occurred in 16 patients (59%), with a median TRBO of 190 days (95% confidence interval: 174-205 days). Reintervention was necessary in 13 of the 16 patients (81%) with RBO, and we were able to remove the initial stents in all the patients who required reintervention.

CONCLUSIONS

A relatively long stent patency period (>6 months) and removability make placement of a modified PS inside bile ducts a viable treatment for unresectable malignant hilar biliary obstruction.

Endoscopic guided biliary drainage: how can we achieve efficient biliary drainage?

Currently, endoscopic retrograde cholangiopancreatography (ERCP) is the preferred procedure for biliary drainage for various pancreatico-biliary disorders. ERCP is successful in 90% of the cases, but is unsuccessful in cases with altered anatomy or with tumors obstructing access to the duodenum. Due to the morbidity and mortality associated with surgical or percutaneous approaches in unsuccessful ERCP cases, biliary endoscopists have been using endoscopic ultrasound-guided biliary drainage (EUS-BD) more frequently within the last decade in different countries. As with any novel advanced endoscopic procedure that incorporates various approaches, advanced endoscopists all over the world have innovated and adopted diverse EUS-BD techniques. Indications for EUS-BD include failed conventional ERCP, altered anatomy, tumor preventing access into the biliary tree and contraindication to percutaneous access (i.e., ascites, etc.). EUS-BD utilizing EUS-guided rendezvous technique is conducted by creating a tract from either the stomach or the duodenum into the bile duct. Although EUS-BD has rapidly been gaining attraction and popularity in the endoscopic world, the indications and methods have yet to be standardized. There are several access routes and techniques that are employed by advanced endoscopists throughout the world for BD. This article reviews the indications and currently practiced EUS-BD techniques, including indications, technical details (intrahepatic or extrahepatic approach), equipment, patient selection, complications, and overall advantages and limitations.

Self expandable metal stents for anastomotic stricture following liver transplant

BACKGROUND

Endoscopic treatment for biliary strictures with plastic stent placement has been used widely. The use of covered self-expandable metal stents (CSEMS) has been reported in anastomotic strictures post liver transplant. The aim of this study was to evaluate the efficacy of different CSEMS in these subjects.

METHODS

A total of 55 patients with anastomotic stricture received CSEMS, which were removed after 3-4 months. There were 19 patients in group A (partially covered SEMS), 21 patients in group B (fully covered SEMS with fins) and 15 patients in group C (fully covered SEMS with flared ends). Technical success, stricture resolution, follows up, and complications were documented.

RESULTS

CSEMS were successfully deployed in all 55 cases. There was no evidence of significant difference with regards to stricture resolution (14 [74%] vs. 15 [71%] vs. 9 [60%] p=0.6630, df=2) or complications between groups. Stent-related complications were as follows: three in group A (2 migration, 1 occlusion), five in group B (4 occlusions, 1 migration), and one proximal migration in group C (p=0.3894, df=2). Three cases required surgery (hepatico-jejunostomy) due to refractory strictures.

CONCLUSIONS

The observed clinical success rate of CSEMS (70.4%) proved to be below the reported one for multiple plastic stents, while no significant differences between CSEMS types were observed.

Multicenter trial evaluating the use of covered self-expanding metal stents in benign biliary strictures: time to revisit our therapeutic options?

BACKGROUND

Covered self-expanding metal stents are being used more frequently in benign biliary strictures (BBS). We report the results of a multicenter study with fully covered self-expanding metal stent (FCSEMS) placement for the management of BBS.

AIM

: To prospectively evaluate the efficacy and safety of FCSEMS in the management of BBS.

PATIENTS AND METHODS

Patients with BBS from 6 tertiary care centers who received FCSEMS with flared ends between April 2009 and October 2010 were included in this retrospective study.Efficacy was measured after removal of FCSEMS by evaluating stricture resolution on the basis of symptom resolution, imaging, laboratory studies, and/or choledochoscopy at removal. Safety profile was evaluated by assessing postprocedural complications.

RESULTS

A total of 133 patients (78, 58.6% males) with a mean age of 59.2±14.8 years with BBS received stents. Of the 133 stents placed, 97 (72.9%) were removed after a mean stent duration of 95.5±48.7 days. Stricture resolution after FCSEMS removal was as follows: postsurgical, 11/12 (91.6%); gallstone-related disease, 16/19 (84.2%); chronic pancreatitis, 26/31 (80.7%); other etiology, 4/5 (80.0%); and anastomotic strictures, 19/31(61.2%). Ninety-four patients were included in the logistic regression analyses. Patients who had indwelling stents for >90 days were 4.3 times more likely to have resolved strictures [odds ratio, 4.3 (95% confidence interval, 1.24-15.09)] and patients with nonmigrated stents were 5.4 times more likely to have resolved strictures [odds ratio, 5.4 (95% confidence interval, 1.001-29.29)].

CONCLUSIONS

FCSEMS for BBS had an acceptable rate of stricture resolution for postsurgical strictures, gallstone-related strictures, and those due to chronic pancreatitis. Predictors for stricture resolution include longer indwell time and absence of migration. Further study is warranted to assess long-term efficacy in a prospective manner with longer than 3-month time of stent indwelling time.

Advances in diagnosis and treatment of hilar cholangiocarcinoma -- a review

Hilar cholangiocarcinoma (HC) is a rare tumor that causes devastating disease. In the late stages, this carcinoma primarily invades the portal vein and metastasizes to the hepatic lobes; it is associated with a poor prognosis. HC is diagnosed by its clinical manifestation and results of imaging techniques such as ultrasound, computed tomography, magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography. Preoperative hepatic bile drainage can improve symptoms associated with insufficient liver and kidney function, coagulopathy, and jaundice. Surgical margin-negative (R0) resection, including major liver resection, is the most effective and potentially curative treatment for HC. If the tumor is not resected, then liver transplantation with adjuvant management can improve survival. We conducted a systematic review of developments in imaging studies and major surgical hepatectomy for HC with positive outcomes regarding quality of life.

Endoscopic Removal of a Proximally Migrated Metal Stent during Balloon Sweeping after Stent Trimming

Placement of a self-expanding metal stent (SEMS) is an effective method for palliation of a malignant biliary obstruction. However, metal stents can cause various complications, including stent migration. Distally migrated metal stents, particularly covered SEMS, can be removed successfully in most cases. Stent trimming using argon plasma coagulation may be helpful in difficult cases despite conventional methods. However, no serious complications related to the trimming or remnant stent removal method have been reported due to the limited number of cases. In particular, proximal migration of a remnant fragmented metal stent after stent trimming followed by balloon sweeping has not been reported. We report an unusual case of proximal migration of a remnant metal stent during balloon sweeping following stent trimming by argon plasma coagulation. The remnant metal stent was successfully removed with rotation technique using a basket and revised endoscopically.

Percutaneous transhepatic hybrid biliary endoprostheses using both plastic and metallic stents for palliative treatment of malignant common bile duct obstruction

To evaluate clinical safety and efficacy of percutaneous transhepatic hybrid biliary prostheses for palliative treatment in patients with common bile duct obstruction caused by advanced malignancies. A total of 13 consecutive patients was treated with percutaneous transhepatic biliary endoprostheses concurrently using both plastic and metallic stents. Serum total bilirubin levels before and after stent placement were evaluated. The technical success rate, the period with no obstructive jaundice, patient survival and complications were also assessed. Median bilirubin levels decreased from 3.8 mg/dL before to 1.2 mg/dL after stent placement, and this difference was statistically significant. The median no-jaundice period after bile duct stent placement was 6.0 months (range: 2-11 months), and overall survival time was 7.0 months. Of the 13 patients, nine did not have recurrent jaundice by the time of death, whereas four (31%) had recurrent jaundice. A second intervention was performed in these four patients. A new plastic stent was placed and jaundice did not recur up to the time of death. No serious complications such as cholangitis, pancreatitis or bile duct perforation developed. Percutaneous transhepatic hybrid biliary endoprostheses using both plastic and metallic stents can be useful as non-invasive palliative treatment to relieve jaundice in patients with malignant obstructive jaundice.

Future developments in biliary stenting

Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting.

Technical tips and issues of biliary stenting, focusing on malignant hilar obstruction

Although there is no survival advantage, inoperable hilar cholangiocarcinoma managed by palliative drainage may benefit from symptomatic improvement. In general, biliary drainage is divided into endoscopic or percutaneous approaches and surgical drainage. Plastic or metal stent is the most preferred device for palliative drainage in endoscopic approach. Considering cost-effectiveness, use of metallic stent is preferred than plastic stents in patients with more than 3 months of life expectancy with inoperable malignant biliary obstruction. In patients with unresectable malignant hilar obstruction, the endoscopic approach with biliary stent placement by experts has been considered as the treatment of choice. However, the endoscopic management of hilar obstruction is often more challenging and complex than distal malignant biliary obstructions. There is still a lack of clear consensus on the use of plastic versus metal stents and unilateral versus bilateral drainage since the decision should be made under many grounds such as the volume of liver drainage more than 50%, life expectancy, and expertise of the facility.

Multicenter Randomized Trial of 10-French versus 11.5-French Plastic Stents for Malignant Biliary Obstruction

Background. There is little prospective data on whether bigger plastic stents are better for patients with malignant biliary obstruction with jaundice. Goals. Multicenter prospective study to compare technical success, clinical response, stent occlusion, and patient survival in patients with malignant biliary obstruction randomized to 10-French or 11.5-French plastic stent. Study. Patients with malignant biliary obstruction were randomized to 10-French or 11.5-French biliary stents. Patients were prospectively assessed for stent occlusion, stent-related interventions, hospital stay, and change in bilirubin. Main outcome measurements included technical success, clinical response, rates of stent occlusion, and survival. Results. 234 patients (47 hilar and 187 common bile duct strictures) were randomized. Outcomes were similar for the 10-French and 11.5-French groups (technical success 99.1% versus 97.4%, P = 0.37). Overall, median stent survival was 213 days, but there was no statistically significant difference in stent survival between 10-French and 11.5-French stents (149 versus 258 days, P = 0.16). Stent survival was significantly longer when placed for common bile duct versus hilar strictures (231 versus 115 days, P = 0.049). Conclusions. The theoretical advantage of improved bile flow for the 11.5-French stent does not translate into more prolonged patency, better clinical response, and longer patient survival than the 10-French stent.

Metal stents: a bridge to surgery in hilar cholangiocarcinoma

BACKGROUND

Obstructive jaundice in patients with hilar cholangiocarcinoma is a known risk factor for hepatic failure after liver resection. Plastic stents are most widely used for preoperative drainage. However, plastic stents are known to have limited patency time and therefore, in palliative settings, the self-expanding metal stent (SEMS) is used. This type of stent has been shown to be superior because it allows for rapid biliary decompression and a reduced complication rate after insertion. This study explores the use of the SEMS for biliary decompression in patients with operable hilar cholangiocarcinoma.

METHODS

A retrospective evaluation of a prospectively maintained database at a tertiary hepatobiliary referral centre was carried out. All patients with resectable cholangiocarcinoma were recorded.

RESULTS

Of 260 patients referred to this unit with cholangiocarcinoma between January 2008 and April 2012, 50 patients presented with operable cholangiocarcinoma and 27 of these had obstructive jaundice requiring stenting. Ten patients were initially treated with SEMSs; no stent failure occurred in these patients. Seventeen patients initially received plastic stents, seven of which failed in the interval between stent placement and laparotomy. These stents were replaced by SEMSs in four patients and by plastic stents in three patients. Median time to laparotomy was 45 days and 68 days in patients with SEMSs and plastic stents, respectively.

CONCLUSIONS

Self-expanding metal stents provide adequate and rapid biliary drainage in patients with obstruction caused by hilar cholangiocarcinoma. No re-interventions were required. This probably reflects the relatively short interval between stent placement and laparotomy.

Reintervention for occluded biliary metal stent for patients with malignant distal biliary stricture

A metal stent has a longer stent patency than a plastic stent in patients with unresectable malignant distal biliary stricture. However, treatment for stent dysfunction of a metal stent remains unresolved. A review of reported articles regarding reintervention for metal stent dysfunction showed that causes of stent dysfunction included tumor ingrowth/overgrowth, stone/sludge/food impaction, and stent migration. Cleaning of the stent is associated with an early relapse of stent dysfunction. Additional placement of a covered metal stent is expected to have a longer stent patency than that of other stents such as uncovered metal stents or plastic stents. It is recommended that occluded covered metal stents be removed if possible. Stent trimming with argon plasma coagulation is sometimes useful for the treatment of stent displacement. No strategy for occluded metal stents has been established yet. Further clinical trials regarding proper treatments are necessary.

Otaru consensus on biliary stenting for unresectable distal malignant biliary obstruction

Endoscopic biliary drainage with biliary stent placement is the treatment of choice for palliation in patients with malignant biliary obstruction caused by unresectable neoplasms. Various biliary stent designs have become available, but lack of a clear consensus persists on the use of covered versus uncovered metal stents in malignant distal bile duct obstructions, and plastic versus metal stents. In 2012, the European Society of Gastrointestinal Endoscopy indicated guidelines for biliary stenting. Accordingly, the consensus meeting for biliary stenting was held at the Endoscopic Forum Japan 2012, and four selected statements related to stent placement for distal malignant biliary obstruction were discussed to produce a consensus. Two of four statements (related to the usefulness of self-expandable metallic stents, and reintervention after stenting) were agreed upon by almost all participants. Nevertheless, our opinions were divided on the other two statements (necessity of sphincterotomy for stenting, and covered metal stent versus uncovered metal stent). We herein report the results of the meeting, and present proposed new statements via discussion.

Necessity for endoscopic sphincterotomy for biliary stenting in cases of malignant biliary obstruction

Endoscopic biliary stenting is a useful way to treat distal malignant biliary strictures that are not eligible for surgery. A 10-Fr plastic or metal stent is used for stenting. Typically, endoscopic sphincterotomy (EST) has often been carried out as a way to prevent pancreatitis after stent placement given the ease of stent insertion, but EST has flaws such as bleeding and stent migration.The present study describes the need for EST prior to stent placement.

Biliary self-expandable metallic stent for unresectable malignant distal biliary obstruction: which is better: covered or uncovered?

Self-expandable metallic stents (SEMS) are a widely accepted biliary endoprosthesis for patients with unresectable malignant distal biliary obstruction. There are two types of SEMS: covered and uncovered. Uncovered SEMS (UCSEMS) embed into the biliary wall due to their mesh structure and self-expandability, and are resistant to migration. However, the disadvantage of UCSEMS is occlusion due to tumor ingrowth (TI) via the stent mesh, and TI is the main cause of UCSEMS occlusion. To overcome this, covered SEMS (CSEMS) were developed and showed longer patency than UCSEMS. However, migration due to the non-embedded stent body is the main cause of CSEMS dysfunction. There are some randomized studies comparing CSEMS and UCSEMS; however, the results are different according to each study. From one meta-analysis, CSEMS showed longer patency than UCSEMS. A literature review revealed that covered SEMS showed longer patency than UCSEMS. Some studies cannot clearly demonstrate the superiority of CSEMS, as the CSEMS used did not prevent TI or migration. Mechanical properties of SEMS may influence the occurrence of complications. A recent clinical study comparing the Covered Wallstent and the Covered WallFlex revealed superiority of the WallFlex for the prevention of migration. Reducing the axial force and increasing the radial force may lead to good results. Migration of CSEMS should be prevented by taking into consideration the mechanical properties of stents and development of anti-migration systems.

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.

Cholangiocarcinoma treatment

Cholangiocarcinoma (CCA) is a tumor of the bile ducts that usually presents with biliary obstruction and has a poor prognosis. The treatment of CCA is challenging as the tumor is usually diagnosed late and the treatments are not very effective except when complete surgical resection is possible. In carefully selected patients, liver transplant can be a curative therapy. In the majority of cases, complete surgical resection is not possible and palliation is the mainstay of treatment. Stenting, using plastic or metallic stents, allows for biliary drainage. Photodynamic therapy plays a role in palliation and might play a role in adjuvant or neoadjuvant therapy. While radiation and chemotherapy can be beneficial, newer ablative techniques and targeted chemotherapies are promising.

Safety and efficacy of radiofrequency ablation in the management of unresectable bile duct and pancreatic cancer: a novel palliation technique

Objectives. Radiofrequency ablation (RFA) has replaced photodynamic therapy for premalignant and malignant lesions of the esophagus. However, there is limited experience in the bile duct. The objective of this pilot study was to assess the safety and efficacy of RFA in malignant biliary strictures.

METHODS

Twenty patients with unresectable malignant biliary strictures underwent RFA with stenting between June 2010 and July 2012. Diameters of the stricture before and after RFA, immediate and 30 day complications and stent patency were recorded prospectively. Results. A total of 25 strictures were treated. Mean stricture length treated was 15.2 mm (SD = 8.7 mm, Range = 3.5-33 mm). Mean stricture diameter before RFA was 1.7 mm (SD = 0.9 mm, Range = 0.5-3.4 mm) while the mean diameter after RFA was 5.2 mm (SD = 2 mm, Range = 2.6-9 mm). There was a significant increase of 3.5 mm (t = 10.8, DF = 24, P value = <.0001) in the bile duct diameter post RFA. Five patients presented with pain after the procedure, but only one developed mild post-ERCP pancreatitis and cholecystitis.

CONCLUSIONS

Radiofrequency ablation can be a safe palliation option for unresectable malignant biliary strictures. A multicenter randomized controlled trial is required to confirm the long term benefits of RFA and stenting compared to stenting alone.

Prospective evaluation of the partially covered nitinol "ComVi" stent for malignant non hilar biliary obstruction

BACKGROUND

Biliary partially covered self-expandable metal stents (PC-SEMS) offer prolonged relief of symptoms of biliary obstruction but may induce complications including pancreatitis, cholecystitis and migration.

AIMS

To assess efficacy and safety of the ComVi partially covered self-expandable metal stents as primary palliative treatment of distal malignant biliary obstruction.

METHODS

Seventy patients (mean age 69.2 years) with distal malignant biliary strictures were prospectively included and underwent endoscopic retrograde cholangio-pancreatography and partially covered self-expandable metal stents placement. Follow-up was done for 12 months. self-expandable metal stents patency, survival and complication-rate after partially covered self-expandable metal stents placement were evaluated.

RESULTS

Overall median survival time was 190 days (30-856). Forty-four patients (62.8%) died after median 175.5 days (30-614) without signs of stent dysfunction; 37 patients (52.8%) were alive after 6 months without signs of self-expandable metal stents occlusion. Survival rapidly dropped between 8 and 12 months after treatment. Survival was not influenced by sex (P = 0.1) or type of neoplasia (P = 0.178). Median survival was longer (254 days [44-836]) in patients who underwent chemotherapy (P < 0.0001). Partially covered self-expandable metal stents occlusion had 24 (35.7%) patients 154 days (35-485) after treatment. Median survival after re-treatment was 66 days (13-597). Cholecystitis occurred in one patient (1.7%).

CONCLUSIONS

The ComVi partially covered self-expandable metal stents is effective for palliation of biliary obstruction secondary to distal malignant biliary strictures. Self-expandable metal stents patency during follow-up is satisfactory without significant complications.