Covered Wallstents for palliation of malignant biliary obstruction: primary stent placement versus reintervention

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.

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

BACKGROUND

The use of duckbill-type anti-reflux metal stents (DMS) in reinterventions after covered metal stent (CMS) dysfunction has been reported in patients with distal malignant biliary obstruction (MBO). However, the superiority of DMS over conventional CMS (c-CMS) has not been established. Therefore, we conducted this retrospective study to evaluate the long-term efficacy and safety of DMS as a second stent in comparison with c-CMS.

METHODS

We investigated consecutive patients with distal MBO due to unresectable pancreatic cancer who underwent reintervention after dysfunction of initial biliary CMS at our institution. We compared causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), adverse events (AEs), and reintervention rates of DMS and c-CMS in this stenting.

RESULTS

A total of 76 patients were included (DMS 41 and c-CMS 35). While overall RBO rates were similar between the two groups (46% vs. 63%, p = 0.172), RBO due to non-occlusion cholangitis tended to be less frequent in the DMS group than in the c-CMS group (2% vs. 14%, p = 0.089). Median TRBO was significantly longer in the DMS group (286 days vs. 112 days, p = 0.029). DMS was identified as the only significant risk factor for TRBO (hazard ratio, 0.52; p = 0.044). Overall AE rates were significantly lower in the DMS group (2% vs. 23%, p = 0.010), with non-occlusion cholangitis being the most common AE in the c-CMS group. Endoscopic reintervention was successfully performed in all patients in both groups, despite failed stent removal in 15% of patients in DMS group.

CONCLUSIONS

DMS was associated with a significantly longer TRBO and lower rate of AEs compared with c-CMS in reinterventions after initial CMS dysfunction. DMS may be preferable to c-CMS as a second stent after biliary CMS dysfunction.

Antireflux metal stent for biliary obstruction: Any benefits?

Endoscopic retrograde cholangiopancreatography with stent placement has been utilized as standard palliative management of distal malignant biliary obstruction (MBO). Compared to plastic stents, metal stents can provide longer-term relief of symptoms. When a large-bore metal stent is placed across the ampulla, patients are predisposed to the risk of cholangitis or stent dysfunction due to reflux of duodenal contents. To mitigate the risk of adverse events associated with the duodenobiliary reflux, efforts have been directed to development of antireflux metal stents (ARMSs). The antireflux property has been introduced through adding of an antireflux valve to the duodenal stent end. Evidence from clinical studies indicates that ARMSs may not only reduce the risk of ascending cholangitis during follow-up but also prolong stent patency time. However, the results of clinical studies testing ARMSs are inconsistent owing to heterogeneous designs of antireflux valves and stent bodies. Metal stents are increasingly indicated for benign biliary strictures and MBO in the setting of neoadjuvant chemotherapy, and therefore, research is warranted to evaluate ARMSs for those indications. Given that endoscopic ultrasound (EUS)-guided transmural biliary drainage has gained popularity, the optimal timing of placing an ARMS in relation to EUS-guided and percutaneous drainage should be investigated. Development and evaluation of ARMSs require an integrative approach utilizing phantom and animal models, measurements of stent mechanical properties, and in vivo functional study after stent placement. In this review article, we summarize updated evidence on ARMSs for MBO and discuss issues that should be addressed in future studies.

Antireflux covered metal stent for nonresectable distal malignant biliary obstruction: Multicenter randomized controlled trial

BACKGROUND AND AIM

An antireflux metal stent (ARMS) for nonresectable distal malignant biliary obstruction (MBO) may prevent recurrent biliary obstruction (RBO) as a result of duodenobiliary reflux and prolong time to RBO (TRBO). Superiority of ARMS over conventional covered self-expandable metal stents (SEMS) has not been fully examined.

METHODS

We conducted a multicenter randomized controlled trial to examine whether TRBO of an ARMS with a funnel-shaped valve was longer than that of a covered SEMS in SEMS-naïve patients. We enrolled 104 patients (52 patients per arm) at 11 hospitals in Japan. Secondary outcomes included causes of RBO, adverse events, and patient survival.

RESULTS

TRBO did not differ significantly between the ARMS and covered SEMS groups (median, 251 vs 351 days, respectively; P = 0.11). RBO as a result of biliary sludge or food impaction was observed in 13% and 9.8% of patients who received an ARMS and covered SEMS, respectively (P = 0.83). ARMS was associated with a higher rate of stent migration compared with the covered SEMS (31% vs 12%, P = 0.038). Overall rates of adverse events were 20% and 18% in the ARMS and covered SEMS groups, respectively (P = 0.97). No significant between-group difference in patient survival was observed (P = 0.26).

CONCLUSIONS

The current ARMS was not associated with longer TRBO compared with the covered SEMS. Modifications including addition of an anti-migration system are required to use the current ARMS as first-line palliative treatment of distal MBO (UMIN-CTR clinical trial registration number: UMIN000014784).

Stenting for Benign and Malignant Biliary Strictures

Benign and malignant biliary strictures are common indications for endoscopic retrograde cholangiopancreatography. Diagnosis involves high-quality cross-sectional imaging and cholangiography with various endoscopic sampling techniques. Treatment options include placement of plastic biliary stents and self-expanding metal stents, which differ in patency duration and cost effectiveness. Whether the etiology is benign or malignant, a multidisciplinary strategy should be implemented. This article will discuss general principles of biliary stenting in both benign and malignant conditions.

Antireflux Metal Stent as a First-Line Metal Stent for Distal Malignant Biliary Obstruction: A Pilot Study

Background/Aims

In distal malignant biliary obstruction, an antireflux metal stent (ARMS) with a funnel-shaped valve is effective as a reintervention for metal stent occlusion caused by reflux. This study sought to evaluate the feasibility of this ARMS as a first-line metal stent.

Methods

Patients with nonresectable distal malignant biliary obstruction were identified between April and December 2014 at three Japanese tertiary centers. We retrospectively evaluated recurrent biliary obstruction and adverse events after ARMS placement.

Results

In total, 20 consecutive patients were included. The most common cause of biliary obstruction was pancreatic cancer (75%). Overall, recurrent biliary obstruction was observed in seven patients (35%), with a median time to recurrent biliary obstruction of 246 days (range, 11 to 246 days). Stent occlusion occurred in five patients (25%), the causes of which were sludge and food impaction in three and two patients, respectively. Stent migration occurred in two patients (10%). The rate of adverse events associated with ARMS was 25%: pancreatitis occurred in three patients, cholecystitis in one and liver abscess in one. No patients experienced non-occlusion cholangitis.

Conclusions

The ARMS as a first-line biliary drainage procedure was feasible. Because the ARMS did not fully prevent stent dysfunction due to reflux, further investigation is warranted.

Radiological interventions in malignant biliary obstruction

Malignant biliary obstruction is commonly caused by gall bladder carcinoma, cholangiocarcinoma and metastatic nodes. Percutaneous interventions play an important role in managing these patients. Biliary drainage, which forms the major bulk of radiological interventions, can be palliative in inoperable patients or pre-operative to improve liver function prior to surgery. Other interventions include cholecystostomy and radiofrequency ablation. We present here the indications, contraindications, technique and complications of the radiological interventions performed in patients with malignant biliary obstruction.

Endoscopic treatment options for cholangiocarcinoma

Cholangiocarcinomas are often locally advanced or have metastasized, and at the time of diagnosis individuals often have a poor prognosis. Endoscopic treatment options traditionally include biliary decompression via stenting to allow for systemic chemotherapy and radiotherapy, with self-expanding metal biliary stents being preferred. Recent developments in locoregional therapy delivered endoscopically, such as photodynamic therapy and radiofrequency abalation, have shown promising results in improving patient survival.

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.

Comparison of the utility of covered metal stents versus uncovered metal stents in the management of malignant biliary strictures in 749 patients

BACKGROUND

Self-expandable metal stents (SEMSs) are used to relieve malignant biliary obstruction.

OBJECTIVE

To compare outcomes between covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (USEMSs) in malignant biliary obstruction.

DESIGN

Retrospective cohort study.

SETTING

Tertiary cancer center.

PATIENTS

Patients with malignant biliary obstruction.

INTERVENTIONS

Placement of CSEMS or USEMS.

MAIN OUTCOME MEASUREMENTS

Time to recurrent biliary obstruction (TRO), overall survival (OS), and adverse events.

RESULTS

From January 2000 to June 2011, 749 patients received SEMSs: 171 CSEMSs and 578 USEMSs. At 1 year, there was no significant difference in the percentage of patients with recurrent obstruction (CSEMSs, 35% vs USEMSs, 38%) and survival (CSEMSs, 45% vs USEMSs, 49%). There was no significant difference in the median OS (CSEMSs, 10.4 months vs USEMSs, 11.8 months; P = .84) and the median TRO (CSEMSs, 15.4 months vs USEMSs, 26.3 months; P = .61). The adverse event rate was 27.5% for the CSEMS group and 27.7% for the USEMS group. Although tumor ingrowth with recurrent obstruction was more common in the USEMS group (76% vs 9%, P < .001), stent migration (36% vs 2%, P < .001) and acute pancreatitis (6% vs 1%, P < .001) were more common in the CSEMS group.

LIMITATIONS

Retrospective study.

CONCLUSIONS

There was no significant difference in the patency rate or overall survival between CSEMSs and USEMSs for malignant distal biliary strictures. The CSEMS group had a significantly higher rate of migration and pancreatitis than the USEMS group. No significant SEMS-related adverse events were observed in patients undergoing neoadjuvant chemoradiation or surgical resection.

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.

Self-expanding metal stents (SEMS) for preoperative biliary decompression in patients with resectable and borderline-resectable pancreatic cancer: outcomes in 241 patients

BACKGROUND AND AIM

Obstructive jaundice caused by distal biliary obstruction can present in up to 70 % of patients with localized cancer of the head of the pancreas. The aim of this study was to report our experience in using self-expanding metal stents (SEMS) for preoperative biliary decompression in patients with resectable and borderline resectable carcinoma of the pancreatic head.

METHODS

We performed a retrospective study evaluating patients from two tertiary referral centers. Two-hundred and forty-one patients with resectable and borderline resectable pancreatic carcinoma underwent ERCP with metal biliary stent placement between September 2006 and August 2011. We assessed the effectiveness of SEMS to adequately decompress the biliary tree, procedural success, patient survival, stent patency, and stent-related complications.

RESULTS

Two-hundred and forty-one patients were evaluated [123 male, mean age (± SD) 67.4 ± 9.8 years; resectable 174, borderline resectable 67]. Patients with borderline-resectable cancer underwent neoadjuvant therapy and restaging before possible curative surgery. Successful placement of a metal biliary stent was achieved in all patients and improved jaundice. Patients were followed for mean duration of 6.3 months. The overall survival was 49 % at 27 months. Fourteen (5.8 %) patients experienced stent occlusion; the mean time to stent occlusion was 6.6 (range 1-20) months. Immediate complications included: post-ERCP pancreatitis (n = 14), stent migration (n = 3), and duodenal perforation (n = 3). Long-term complications included stent migration (n = 9) and hepatic abscess (n = 1). A total of 144/174 patients deemed to have resectable cancer at time of diagnosis underwent curative surgery. Due to disease progression or the discovery of metastasis after neoadjuvant therapy, only 22/67 patients with borderline-resectable cancer underwent curative surgery.

CONCLUSIONS

SEMS should be considered for patients with obstructive jaundice and resectable or borderline resectable pancreatic cancer, especially if surgery is not planned immediately as a result of preoperative chemoradiation. These stents appear to be safe and effective.

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.

Endoscopic management of malignant bile duct strictures

Malignant biliary obstruction can arise from intrahepatic, extrahepatic, and hilar locations from either primary or metastatic disease. Biliary-enteric surgical bypass has been surpassed in the last 20 years by endoscopic balloon dilation and stenting. The goal of stenting for biliary decompression is to palliate obstructive symptoms; it has not been shown that survival is affected by stenting alone. Novel endoscopic therapies, including photodynamic therapy and radiofrequency ablation, have been evaluated and show promise. Both therapies seem to be safe and effective in the treatment of malignant bile duct strictures but are in need of prospective studies of longer duration.

Biliary drainage for obstructive jaundice caused by unresectable hepatocellular carcinoma: the endoscopic versus percutaneous approach

BACKGROUND

For palliative treatment of the obstructive jaundice associated with unresectable hepatocellular carcinoma (HCC), percutaneous transhepatic biliary drainage (PTBD) or endoscopic retrograde biliary drainage (ERBD) has been performed. PTBD is preferred as an initial procedure. Little is known about the better option for patients with obstructive jaundice caused by unresectable HCC.

METHODS

Sixty patients who had received ERBD or PTBD for the palliative treatment of obstructive jaundice caused by unresectable HCC between January 2006 and May 2010 were included in this retrospective study. Successful drainage, drainage patency, and the overall survival of patients were evaluated.

RESULTS

Univariate analysis revealed that the overall frequency of successful drainage was higher in the ERBD group (22/29, 75.9%) than in the PTBD group (15/31, 48.4%) (P=0.029); but multivariate analysis showed marginal significance (P=0.057). The duration of drainage patency was longer in the ERBD group than in the PTBD group (82 vs 37 days, respectively, P=0.020). Regardless of what procedure was performed, the median survival time of patients who had a successful drainage was much longer than that of the patients who did not have a successful drainage (143 vs 38 days, respectively, P<0.001).

CONCLUSION

Besides PTBD, ERBD may be used as the initial treatment option to improve obstructive jaundice in patients with unresectable HCC if there is a longer duration of drainage patency after a successful drainage.

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

BACKGROUND

Covered or uncovered self expandable metallic stents (SEMS) placed in patients with malignant biliary obstruction can occlude in 19-40 %, but optimal management is unclear.

AIM

We sought to summarize current evidence regarding management of occluded SEMS in patients with malignant biliary obstruction.

METHODS

Two investigators independently searched Pubmed, Embase, and Web of Science using pre-defined search criteria, and reviewed bibliographies of included studies. Data were independently abstracted by two investigators, and analyzed using RevMan. We compared strategies of second SEMS versus plastic stents with respect to the following outcomes: rate of second stent re-occlusion, duration of second stent patency, and survival.

RESULTS

Ten retrospective studies met inclusion criteria for the systematic review. Management options described were placement of an uncovered SEMS (n = 125), covered SEMS (n = 106), plastic stent (n = 135), percutaneous biliary drain (n = 7), mechanical cleaning (n = 18), or microwave coagulation (n = 7). Relative risk of re-occlusion was not significantly different in patients with second SEMS compared to plastic stents (RR 1.24, 95 % CI 0.92, 1.67, I(2) = 0, p 0.16). Duration of second stent patency was not significantly different between patients who received second SEMS versus plastic stents (weighted mean difference 0.46, 95 % CI -0.30, 1.23, I(2) = 83 %). Survival was not significantly different among patients who received plastic stents versus SEMS (weighted mean difference -1.13, 95 % CI -2.33, 0.07, I(2) 86 %, p = 0.07).

CONCLUSIONS

Among patients with malignant biliary obstruction and occluded SEMS, available evidence suggests a strategy of placing a plastic stent may be as effective as second SEMS. Limitations of these findings were that all studies were retrospective and heterogeneity between studies was detected for two of the outcomes.

Feasibility of placing a modified fully covered self-expandable metal stent above the papilla to minimize stent-induced bile duct injury in patients with refractory benign biliary strictures (with videos)

BACKGROUND

Endoscopic placement of fully covered self-expandable metal stents (FCSEMS) has been attempted to manage benign biliary strictures, but currently available FCSEMSs may be associated with unintended complications, including de novo strictures, in patients with normal life expectancy.

OBJECTIVE

To evaluate the feasibility of an intraductally placed modified FCSEMS to minimize stent-induced bile duct injury in patients with benign biliary strictures.

DESIGN

Prospective observational clinical feasibility study.

SETTING

Tertiary-care academic center.

PATIENTS

This study involved 21 patients with symptomatic benign biliary strictures in whom conventional endoscopic management failed.

INTERVENTION

Strictured segments were 15 mm above the ampulla of Vater. The modified FCSEMS has convex margins, a lasso, and an anti-migrating waist on the central portion. Stents were placed entirely above the papilla and removed after 3 to 5 months.

MAIN OUTCOME MEASUREMENTS

Success, complications, removability, midterm outcome.

RESULTS

FCSEMSs were successfully placed inside the bile duct in all patients. No episodes of pancreatitis, cholangitis, or sepsis were noted during the stenting period. Stent migration occurred in 4 patients (19.0%), but 3 were asymptomatic during follow-up. All stents were removed successfully with rat-tooth forceps without complications. Post-stenting cholangiograms showed improvement of strictures in 20 of 21 patients, without de novo focal stricture. The clinical success rate was 95.2%, with one recurrent stricture.

LIMITATIONS

The small number and lack of comparison with other types of FCSEMSs.

CONCLUSION

Temporary intraductal placement of a newly modified FCSEMS effectively improved strictures and prevented potential stent-induced complications in patients with benign biliary strictures. Controlled large-scale trials are needed to confirm the long-term efficacy.

Recent advances of biliary stent management

Recent progress in chemotherapy has prolonged the survival of patients with malignant biliary strictures, leading to increased rates of stent occlusion. Even we employed metallic stents which contributed to higher rates and longer durations of patency, and occlusion of covered metallic stents now occurs in about half of all patients during their survival. We investigated the complication and patency rate for the removal of covered metallic stents, and found that the durations were similar for initial stent placement and re-intervention. In order to preserve patient quality of life, we currently recommend the use of covered metallic stents for patients with malignant biliary obstruction because of their removability and longest patency duration, even though uncovered metallic stents have similar patency durations.

Partially covered self-expanding metal stent for unresectable malignant extrahepatic biliary obstruction: results of a large prospective series

BACKGROUND

Endoscopic biliary stenting is a well-established palliative treatment in patients with unresectable malignant biliary strictures. Obstruction of uncovered self-expanding metal stent (SEMS) due to tumor ingrowth is the most frequent complication. Partially covered SEMS might increase stent patency but could favor complications related to stent covering, such as pancreatitis, cholecystitis, and migration. The aim of this study was to evaluate the efficacy and safety of partially covered SEMS in patients with an unresectable malignant biliary stricture.

METHODS

Patients with malignant extrahepatic biliary obstruction treated endoscopically with partially covered SEMS were included in this multicenter, prospective, nonrandomized study.

RESULTS

One hundred ninety-nine patients were endoscopically treated with partially covered SEMS in 32 Spanish hospitals. Clinical success after deep cannulation was 96%. Early complications occurred in 4% (3 pancreatitis, 2 cholangitis, 1 hemorrhage, 1 perforation, and 1 cholecystitis). Late complications occurred in 19.5% (18 obstructions, 10 migrations, 6 cholangitis without obstruction, 3 acute cholecystitis, and 2 pancreatitis), with no tumor ingrowth in any case. Median stent patency was 138.9 ± 112.6 days. One-year actuarial probability of stent patency was 70% and that of nonmigration was 86%. Multivariate analysis showed adjuvant radio- or chemotherapy as the only independent predictive factor of stent patency and previous insertion of a biliary stent was the only predictive factor of migration.

CONCLUSIONS

The partially covered SEMS was easily inserted, had a high clinical success rate, and prevented tumor ingrowth. The incidence of possible complications related to stent coverage, namely, migration, pancreatitis, and cholecystitis, was lower than in previously published series.

A multicenter prospective study of the short-term outcome of a newly developed partially covered self-expandable metallic biliary stent (WallFlex(®))

BACKGROUND

Self-expandable metallic stent (SEMS) placement is a widely used, effective therapy for unresectable malignant stricture of the lower bile duct.

AIMS

We evaluated the short-term outcome of the newly developed WallFlex(®) Biliary RX Partially Covered Stent in patients with malignant lower and middle biliary stricture in five tertiary referral centers.

METHODS

The subjects of this study were 52 patients in whom WallFlex(®) Biliary RX Stents were inserted into the bile duct for malignant stenosis of the middle and lower bile duct at five medical facilities between April 2009 and November 2009.

RESULTS

The stent placement success rate was 100%. Effective biliary decompression was achieved in all patients. The incidence of early complications was 7.7% (4/52). Stent occlusion occurred in two patients (3.8%) (one dislocation, one migration); cholecystitis occurred in two patients (3.8%). Neither acute pancreatitis nor stent kinking in the bile duct occurred.

CONCLUSIONS

The present results revealed that the new WallFlex(®) Biliary RX Partially Covered SEMSs were useful for the short-term relief of biliary obstruction due to unresectable distal biliary malignancies.

Endoscopic biliary sphincterotomy is not required for transpapillary SEMS placement for biliary obstruction

BACKGROUND

Endoscopic retrograde cholangiopancreatography with biliary self-expanding metal stent placement is the preferred method of providing biliary drainage for pancreaticobiliary malignancies. Some endoscopists routinely perform biliary sphincterotomy to facilitate biliary stent placement and potentially minimize pancreatitis with transpapillary self-expanding metal stent placement.

AIMS

Our hypothesis was that biliary sphincterotomy has no effect on the success rate of transpapillary self-expanding metal stent placement and increases procedure-related complications.

METHODS

In a retrospective analysis, outcomes of two groups were compared: (1) self-expanding metal stent placement without biliary sphincterotomy, (2) self-expanding metal stent placement with biliary sphincterotomy during the same procedure. Complications and stent patency rates were evaluated.

RESULTS

There were 104 subjects included in the study. Post-sphincterotomy bleeding (p = 0.001) was associated with biliary sphincterotomy performed immediately prior to self-expanding metal stent placement. Importantly, self-expanding metal stent placement without biliary sphincterotomy was always technically successful and self-expanding metal stent placement without biliary sphincterotomy was not associated with pancreatitis.

CONCLUSIONS

Patients who undergo biliary sphincterotomy during transpapillary self-expanding metal stent placement experience more immediate complications than those who do not. Biliary sphincterotomy was not associated with longer stent patency. Self-expanding metal stent placement without a biliary sphincterotomy was not associated with pancreatitis regardless of the type of self-expanding metal stent used (covered or uncovered). Of the patients without a biliary sphincterotomy, 100% had successful stent placement, further arguing against its use in this setting.

Endoscopic stenting for palliation of malignant biliary obstruction

Malignant biliary obstruction results in jaundice, often with symptoms that decrease the quality of life. Biliary stent placement has largely supplanted surgical bypass for palliation of malignant biliary obstruction. Traditional rigid plastic stents are commonly used, inexpensive and easily removed, although with limited duration of stent patency. Self-expandable metal stents (SEMS) attain larger luminal diameters and provide longer patency than traditional rigid plastic stents in patients with distal bile duct obstruction. SEMS are composed of a variety of metals and can be uncoated, partially covered, or fully covered. Data do not support a prolongation of patency with covered SEMS for distal obstruction, although they have the potential for removability. The data to support SEMS for palliation of hilar biliary obstruction are not as convincing and reintervention for stent occlusion can be difficult. In this article, the design and performance of expandable metal stents for treatment of malignant biliary obstruction will be reviewed.

Covered versus uncovered self-expandable nitinol stents in the palliative treatment of malignant distal biliary obstruction: results from a randomized, multicenter study

BACKGROUND

Covered biliary metal stents have been developed to prevent tumor ingrowth. Previous comparative studies are limited and often include few patients.

OBJECTIVE

To compare differences in stent patency, patient survival, and complication rates between covered and uncovered nitinol stents in patients with malignant biliary obstruction.

DESIGN

Randomized, multicenter trial conducted between January 2006 and October 2008.

SETTING

Ten sites serving a total catchment area of approximately 2.8 million inhabitants.

PATIENTS

A total of 400 patients with unresectable distal malignant biliary obstruction.

INTERVENTIONS

ERCP with insertion of covered or uncovered metal stent. Follow-up conducted monthly for symptoms indicating stent obstruction.

MAIN OUTCOME MEASUREMENTS

Time to stent failure, survival time, and complication rate.

RESULTS

The patient survival times were 116 days (interquartile range 242 days) and 174 days (interquartile range 284 days) in the covered and uncovered stent groups, respectively (P = .320). The first quartile stent patency time was 154 days in the covered stent group and 199 days in the uncovered stent group (P = .326). There was no difference in the incidence of pancreatitis or cholecystitis between the 2 groups. Stent migration occurred in 6 patients (3%) in the covered group and in no patients in the uncovered group (P = .030).

LIMITATIONS

Randomization was not blinded.

CONCLUSIONS

There were no significant differences in stent patency time, patient survival time, or complication rates between covered and uncovered nitinol metal stents in the palliative treatment of malignant distal biliary obstruction. However, covered stents migrated significantly more often compared with uncovered stents, and tumor ingrowth was more frequent in uncovered stents.

A randomized trial comparing uncovered and partially covered self-expandable metal stents in the palliation of distal malignant biliary obstruction

BACKGROUND

The most common complication of uncovered biliary self-expandable metal stents (SEMSs) is tumor ingrowth. The addition of an impenetrable covering may prolong stent patency.

OBJECTIVE

To compare stent patency between uncovered and partially covered SEMSs in malignant biliary obstruction.

DESIGN

Multicenter randomized trial.

SETTING

Four teaching hospitals.

PATIENTS

Adults with inoperable distal malignant biliary obstruction.

INTERVENTIONS

Uncovered or partially covered SEMS insertion.

MAIN OUTCOME MEASURES

Time to recurrent biliary obstruction, patient survival, serious adverse events, and mechanism of recurrent biliary obstruction.

RESULTS

From October 2002 to May 2008, 129 patients were randomized. Recurrent biliary obstruction was observed in 11 of 61 uncovered SEMSs (18%) and 20 of 68 partially covered SEMSs (29%). The median times to recurrent biliary obstruction were 711 days and 357 days for the uncovered and partially covered SEMS groups, respectively (P = .530). Median patient survival was 239 days for the uncovered SEMS and 227 days for the partially covered SEMS groups (P = .997). Serious adverse events occurred in 27 (44%) and 42 (62%) patients in the uncovered and partially covered SEMS groups, respectively (P = .046). None of the uncovered and 8 (12%) of the partially covered SEMSs migrated (P = .0061).

LIMITATIONS

Intended sample size was not reached. Allocation to treatment groups was unequal.

CONCLUSIONS

There was no significant difference in time to recurrent biliary obstruction or patient survival between the partially covered and uncovered SEMS groups. Partially covered SEMSs were associated with more serious adverse events, particularly migration.

Modified fully covered self-expandable metal stents with antimigration features for benign pancreatic-duct strictures in advanced chronic pancreatitis, with a focus on the safety profile and reducing migration

BACKGROUND

Fully covered self-expandable metal stent (FCSEMS) placement has recently been tried in the management of refractory pancreatic-duct strictures associated with advanced chronic pancreatitis. The major limitation of FCSEMSs was frequent migration.

OBJECTIVE

To assess the safety, migration rate, and removability of modified FCSEMSs with antimigration features used for the treatment of benign pancreatic-duct strictures.

DESIGN

Prospective study.

SETTING

Tertiary academic center.

PATIENTS

Thirty-two patients with chronic painful pancreatitis and dominant ductal stricture.

INTERVENTIONS

Transpapillary endoscopic placement of FCSEMSs in the pancreatic duct with removal after 3 months.

MAIN OUTCOME MEASUREMENTS

Technical and functional success and adverse events associated with the placement of metal stents.

RESULTS

FCSEMSs were successfully placed in all patients through the major (n = 27) or minor (n = 5) duodenal papilla. All patients achieved pain relief from stent placement. There was no occurrence of stent-induced pancreatitis or pancreatic sepsis. No stent migrated, and all stents were easily removed. Follow-up ERCP 3 months after stent placement showed resolution of duct strictures in all patients. Pancreatograms obtained at FCSEMS removal displayed de novo focal pancreatic duct strictures in 5 patients, but all were asymptomatic.

LIMITATIONS

No long-term follow-up.

CONCLUSIONS

Temporary 3-month placement of FCSEMSs was effective in resolving pancreatic-duct strictures in chronic pancreatitis, with an acceptable morbidity profile. Modified FCSEMSs can prevent stent migration, but may be associated with de novo duct strictures. Further trials are needed to assess long-term safety and efficacy.