Adjuvant therapies using biliary stenting for malignant biliary obstruction

The aim of this study was to analyze the patency of expandable metallic stents in malignant biliary obstruction and to evaluate the efficacy of adjuvant therapy accompanied by biliary stenting. We analyzed 29 patients in whom bile duct stenting was performed for malignant biliary obstruction. Their types of disease were: hilar ductal carcinoma (n = 8), gallbladder carcinoma (n = 11), and pancreatic carcinoma (n = 10). Initially, 46 expandable metallic stents were placed in 29 patients. In 23 of the 29 patients, adjuvant therapy was administered. Seventeen patients underwent radiotherapy, and 16 patients received various systemic chemotherapies. In principle, hyperthermia was performed twice a week, simultaneously with radiotherapy. Patient survival and the probability of stent patency were calculated using actuarial life table analysis. There was no significant difference in stent patency among the patients according to type of disease. Hyperthermia did not influence the stent patency rate. The median stent patency time was significantly greater in the chemo-radiation group than in the no-adjuvant therapy group: 182 days versus 68 days, respectively (P = 0.017). Moreover, a significant increase was seen in the median survival time in the chemo-radiation group: 261 days versus 109 days (P = 0.0337). Complications occurred in 9 patients (31.0%). Stent occlusion occurred in 6 patients (20.7%), with all of these patients managed successfully using a transhepatically placed new expandable metallic stent, employing the stent-in-stent method. Stent migration occurred in 2 patients after radiotherapy. Adjuvant therapies such as radiotherapy and systemic chemotherapy, in combination with stent insertion, resulted in an increase in the patency period of expandable metallic stents and in increased patient survival time.     

Expandable metal biliary stenting in patients with recurrent premature polyethylene stent occlusion

OBJECTIVES: Expandable metal stents are currently used to treat biliary tract obstruction. Few data exist on the role of metal stents in patients with recurrent premature plastic biliary stent occlusion. We report our preliminary results using an expandable metal biliary stent with enhanced stent flexibility in this group of patients. Our aim was to assess the efficacy of the Diamond biliary stent in the treatment of recurrent premature biliary plastic stent blockage. METHODS: From September 1997 to June 1998, six patients with inoperable biliary obstruction and at least one prior episode of plastic stent occlusion were treated with an expandable metal biliary prosthesis. There were four women and six men, with a mean age of 73+/-11 yr. Five patients had malignant biliary obstruction, and one inoperable patient had a biliary stricture secondary to chronic pancreatitis. Patients were followed-up prospectively until either stent occlusion or death. The patency duration of the metal stents was compared to that of the most recently placed plastic stents. RESULTS: All stents were successfully inserted endoscopically with visualized biliary drainage. No significant immediate postprocedural complications were noted. Median time from initial diagnosis of biliary obstruction to metal stent insertion was 35 wk (range 7-142), during which time patients had occluded a median of 4.5 plastic stents (range 2-5). Median patient survival was 117 days (15-312) and median time to blockage of the last plastic stent was 25.5 days (range 10-90 days). Three cases of metal stent occlusion occurred. One patient had early stent occlusion at 9 days because of debris and sludge clogging the metal stent. Two other patients developed stent occlusion at 120 and 157 days. Two stents remained patent until the patients' deaths at 15 and 87 days. Overall median stent patency was 139 days. The three patients who developed stent occlusion were treated with successful insertion of one or more plastic stents through the existing metal stent. Duration of metal stent patency was significantly longer than that of the last plastic stent (58.8 days longer; 95% CI [6.4, 111]; p = 0.03). CONCLUSIONS: Metal biliary prostheses represent an effective management strategy for recurrent plastic biliary stent obstruction. Patients in this subgroup may have a shorter duration of metal stent patency than the reported duration of stent patency in patients receiving initial metal stent placement. However the duration of patency still seems to be significantly longer than that of the most recently placed plastic stent.     

The Tannenbaum Stent: A New Plastic Biliary Stent without Side Holes

Objective: Clogging of plastic biliary stents used in malignant biliary obstruction remains a major problem. In vitro studies have shown that side holes, a standard feature of commercially available stents, may contribute to stent clogging. In a pilot study, we designed and prospectively evaluated a new biliary stent without side holes (Tannenbaum stent).
Methods: Over a 12-month period, 55 consecutive patients (mean age 75 yr) with malignant distal common bile duct obstruction and without papillary or duodenal tumor infiltration underwent endoscopic placement of the Tannenbaum stent for the palliative treatment of jaundice.
Results: Tannenbaum stent insertion was technically successful on the first attempt in all patients and was accompanied by a significant reduction in mean serum bilirubin levels (10.1–1.6 mg%). Fifty-one patients were followed until death (median survival of 130 days); the symptomatic occlusion rate was 16%, the dislocation rate was 8%, and the median stent patency was 64 wk. Aside from stent clogging, there were no complications.
Conclusion: The Tannenbaum stent provided effective palliative biliary decompression in all patients. The patency rate was longer than that reported in the literature for conventional plastic stents with side holes and compared favorably with patency rates that have been reported for the metallic expandable biliary stents. The results of this pilot study are encouraging and warrant further studies.     

Efficacy and safety of the covered Wallstent in patients with distal malignant biliary obstruction

BACKGROUND: The aim of this study was to evaluate the efficacy and the safety of the covered Wallstent, a commercially available silicone-covered, self-expandable metallic stent (covered Wallstent), for the treatment of distal malignant biliary obstruction. METHODS: Sixty-nine consecutive patients with unresectable distal malignant biliary obstruction who underwent covered Wallstent placement between October 2001 and October 2003 were studied at 4 affiliated hospitals. RESULTS: Mean stent patency and mean survival were 139.1 days and 200.9 days, respectively. Stent occlusion occurred in 7 cases (10.1%), but tumor ingrowth was not observed. Seventeen complications, including 5 cholangitis (7.2%), 4 stent migration (5.8%), 4 cholecystitis (5.8%), and 4 pancreatitis (5.8%) were observed in 16 patients (23.2%). Stent misplacement was observed in 7 patients (10.1%). CONCLUSIONS: Covered Wallstent is effective in preventing tumor ingrowth for the treatment of distal malignant biliary obstruction. However, the overall complication rate may be higher than uncovered self-expanding metal stents and covered self-expanding metal stents of different design.     

A three year follow up of self expanding metal stents in the endoscopic palliation of longterm survivors with malignant biliary obstruction.

Effective palliation of malignant biliary obstruction with conventional 10 or 12 French gauge straight polyethylene endoprostheses is limited by stent occlusion, which typically occurs four to five months after insertion. Short term follow up studies of self expanding metal stents (Wallstent, Schneider, UK) in the treatment of patients with malignant biliary obstruction have shown that their use is associated with fewer episodes of stent occlusion compared with plastic stents. There are few data, however, on the longterm patency and durability of metal stents in malignant disease. Between May 1989 and May 1992, metal stents were inserted in 28 patients with malignant bile duct strictures secondary to ampullary tumour (n = 10), pancreatic carcinoma (n = 10), cholangiocarcinoma (n = 7), and porta hepatis nodes from colorectal carcinoma (n = 1). The follow up of these patients until May 1993 is reported with a median follow up of 14.6 months. Twenty two of 28 (78.6%) patients remained free of jaundice or cholangitis. The median period of stent patency was 8.2 months (range 1.0-32.5). Thirteen patients represented with jaundice or cholangitis and endoscopic retrograde cholangiopancreatography showed evidence of stent occlusion due to tumour ingrowth. Successful clearance of metal stents was achieved by balloon trawling, or insertion of a polyethylene stent. In conclusion, metal stents provide improved longterm palliation for patients with malignant biliary strictures with fewer episodes of occlusion compared with conventional stents.     

Metallic stent deployment in endosonography‐guided biliary drainage: Long‐term follow‐up results in patients with bilio‐enteric anastomosis

Background and Aim: Although reports on endosonography‐guided biliary drainage (ESBD) have been increasing, only a few reports on deployment of a self‐expandable metal stents (SEMS) have been reported. The aim of the present study was to evaluate the safety and efficacy of SEMS deployment in ESBD. Methods: Of 42 patients who underwent ESBD during the period from January 2007 to August 2011, 21 patients with unresectable malignant biliary obstruction in whom SEMS deployment had been attempted were included. In the first session, a plastic stent or SEMS was placed in a bilio‐enteric anastomosis (BEA) method. SEMS was deployed with the one‐step technique or with replacement of a plastic stent with a SEMS in the second session. The technical success, early and late complications, and stent patency of SEMS were evaluated. Results: One‐step SEMS deployment was attempted in seven patients, and SEMS was deployed with stent exchange in 14. SEMS deployment was successful in all patients without any complications. Finally, SEMS was placed in a BEA method in 16 patients (extrahepatic bile duct, 13; intrahepatic bile duct, three), and with antegrade deployment in five. Late complications occurred in three patients who underwent deployment of SEMS in a BEA method (stent obstruction in two and reflux cholangitis in one). The mean stent patency period was 433 days. Conclusions: As SEMS deployment in ESBD is safe and provides long stent patency, a SEMS seems to be the stent of choice in ESBD for patients with unresectable malignant biliary obstruction in whom long survival is expected.     

NEW METHOD OF COVERED WALLSTENTS FOR DISTAL MALIGNANT BILIARY OBSTRUCTION TO REDUCE EARLY STENT‐RELATED COMPLICATIONS BASED ON CHARACTERISTICS

Aim: We previously reported a low occlusion rate with covered Wallstents for malignant biliary obstruction, but stent‐related complications other than occlusion posed a problem. A modified covered Wallstent insertion method based on stent characteristics was evaluated to reduce stent‐related complications. Methods: A total of 138 patients with distal malignant biliary obstruction received covered Wallstent placement. From October 2001 to October 2003, 69 patients received covered Wallstent placement (Group 1). Thereafter, we modified our stent insertion method and 69 patients received stent placement using this modified method from November 2003 to January 2007 (Group 2). The modified insertion method consists of endoscopic sphincterotomy carried out in patients without pancreatic duct invasion and longer stent placement with the center of the stent located in the center of the biliary stricture to prevent pancreatitis, kinking of the bile duct, and stent dislocation. A comparative analysis was carried out using prospectively collected data in these two cohorts. Results: Tumor ingrowth was not observed, and stent occlusion rate was 18.8% in Group 1 and 23.2% in Group 2. The overall rates of stent‐related complications did not differ (39.1% in Group 1 and 30.4% in Group 2), but stent‐related complications within 3 months decreased from 22 episodes in Group 1 to 13 episodes in Group 2. Median event‐free survival was prolonged by modified stent insertion method (125 days in Group 1 and 268 days in Group 2, P = 0.020), although cumulative survival and stent patency were not significantly different. Conclusions: Our modified method of covered Wallstent placement showed improved event‐free survival.     

Microwave coagulation versus insertion of a second stent for occluded biliary metal stent.

BACKGROUND/AIMS: There is no consensus regarding optimal management of self-expandable metallic stent occlusion. We investigated the efficacy of microwave coagulation therapy for recanalization as compared to second stent placement. METHODOLOGY: Sixty patients with malignant obstruction of the common bile duct were treated with metal stent placement from January 1992 to July 1999. Of these, 13 patients subsequently developed stent occlusion due to tumor ingrowth. We compared stent patency and patient survival rates after microwave coagulation to those after insertion of a second stent. The influence of the duration of patency of the first stent on the second stent patency was also evaluated. RESULTS: Of the 13 patients with stent occlusion, 7 were treated with microwave coagulation therapy, and 6 with insertion of a second metal stent. In all cases, occluded stents were successfully recanalized without any complications. There was no significant difference in duration of first stent patency between the two groups. The median duration of second stent patency was prolonged in microwave-treated patients (152 days vs. 104 days, P > 0.05). The median duration of patient survival after last recanalizing procedure was also prolonged in microwave-treated patients (131 days vs. 78 days, P > 0.05). Microwave energy did not induce destruction of the stent filament. CONCLUSIONS: Microwave coagulation did not offer significantly longer duration of stent patency and patient survival compared to insertion of a second metal stent. However, this procedure is safe, feasible, and certainly as good as a second stent placement. It may be an alternative to insertion of a second stent within the occluded stent.     

Uncovered Hanaro Versus Luminex metal stents for palliation of malignant biliary strictures

BACKGROUND: Endoscopic stent insertion is the optimum method of palliation for malignant biliary obstruction. Various types of self-expanding metal stents have been introduced in the market. Whether one type of stents is superior to the others in terms of stent patency remains undefined. GOALS: This randomized trial compared 2 uncovered metal stents with similar technical characteristics, but significant cost difference, in the palliation of inoperable malignant biliary strictures. STUDY: Ninety-two patients with inoperable biliary obstruction were randomized to receive either a 10-mm diameter Hanaro or Luminex uncovered metal stent. The duration of stent patency, the overall patient survival, the mechanism of stent occlusion, and the adverse events were analyzed. RESULTS: Eighty-nine patients were included in the analysis; 44 received Hanaro stents and 45 Luminex stents. The overall median patency rates between the 2 stents did not differ (328 d for the Hanaro vs. 289 d for the Luminex stent; P=0.815). Similarly, no difference was found between the overall median survival rates by the 2 stents (347 d for the Hanaro vs. 307 d for the Luminex stent; P=0.654). Two major procedure-related complications occurred, perforation (Hanaro stent) and proximal stent migration (Luminex stent). Stent occlusion requiring reintervention occurred in 25 patients (11 with the Hanaro vs. 14 with the Luminex stent; P=0.521). CONCLUSIONS: The 2 uncovered metal stents are comparable in terms of placement, occlusion rates, overall stent patency, and patient survival; Hanaro stent insertion, however, seems to be a cost-saving strategy at least in Greece.     

A prospective randomised study of "covered" versus "uncovered" diamond stents for the management of distal malignant biliary obstruction

BACKGROUND AND AIM: Covered self-expandable metal stents (EMS) were recently developed to overcome tumour ingrowth in conventional EMS. However, supporting evidence for the efficacy of covered EMS is lacking. PATIENTS AND METHODS: We enrolled 112 patients with unresectable distal biliary malignancies. They were randomly assigned to polyurethane covered (n = 57) or original diamond stent (n = 55). RESULTS: Stent occlusion occurred in eight patients (14%) after a mean of 304 days in the covered group, and in 21 patients (38%) after a mean of 166 days in the uncovered group. The incidence of covered EMS occlusion was significantly lower than that of uncovered EMS (p = 0.0032). The cumulative stent patency of covered stents was significantly higher than that of uncovered stents (p = 0.0066). No tumour ingrowth occurred in the covered group while it was observed in 15 patients in the uncovered group. In subgroup analysis, the cumulative patency of the covered EMS was significantly higher in pancreatic cancer (p = 0.0363) and metastatic lymph nodes (p = 0.0354). There was no significant difference in survival between the two groups. Acute cholecystitis was observed in two of the covered group and in none of the uncovered group. Mild pancreatitis occurred in five of the covered group and in one of the uncovered group. CONCLUSIONS: Covered diamond stents successfully prevented tumour ingrowth and were significantly superior to uncovered stents for the treatment of patients with distal malignant biliary obstruction. However, careful attention must be paid to complications specific to covered self-expandable metal stents, such as acute cholecystitis and pancreatitis.     

Photodynamic therapy of malignant biliary strictures using meso-tetrahydroxyphenylchlorin

OBJECTIVES: The palliation of patients with malignant bile duct obstruction using metal or plastic biliary stents may be limited by stent occlusion. The aim of this study was to determine the safety and efficacy of endoscopically delivered meso-tetrahydroxyphenyl chlorin photodynamic therapy in the treatment of irresectable malignant biliary strictures and recurrent stent occlusion. METHODS: Thirteen patients with malignant biliary obstruction owing to carcinoma of the biliary tract (n=9), pancreas (n=3) or stomach (n=1), were studied. All had been initially palliated with metal (n=10) or polyethylene (n=3) biliary stents, but presented with recurrent obstructive jaundice because of local tumour progression. Patients received meso-tetrahydroxyphenyl chlorin 0.15 mg/kg intravenously 72 h before endoluminal light activation with an endoscopically placed optical fibre, followed by polyethylene stent insertion. RESULTS: Before photodynamic therapy, patients had a median of three (range 0-5) stent occlusions in the preceding 11 (2-22) months, with a median patency of plastic stents placed inside metal bile duct stents for recurrent stent occlusion of 3.5 (0.5-13) months. After photodynamic treatment, tumour necrosis and/or metal stent recanalization was seen in all patients, with a median of 0 (0-3) stent occlusions during 7 (1-43) months follow-up. The median patency of plastic stents placed inside metal stents after photodynamic therapy was 5 (1-43) months. The median survival after diagnosis and photodynamic therapy administration was 21 (10-56) and 8 (1-43) months, respectively. Photodynamic therapy was generally well tolerated but two patients developed cholangitis within the first week, complicated in one by a fatal liver abscess and two developed haemobilia within 4 weeks of treatment, one of whom died with a gall bladder empyema. CONCLUSION: In patients with malignant biliary obstruction, endoscopically delivered meso-tetrahydroxyphenyl chlorin photodynamic therapy causes efficient tumour necrosis and recanalization of blocked metal stents, but there is a significant risk of complications.     

Efficacy of the Za self-expandable metal stent for palliation of malignant biliary obstruction

BACKGROUND: The efficacy and safety of the uncoated self-expandable Za metal stent for palliation of malignant distal biliary obstruction was prospectively analyzed. METHODS: Twenty-one patients with unresectable malignant tumors involving mid to distal common bile duct who presented with obstructive jaundice underwent endoscopic implantation of an uncoated self-expandable metal stent. Technical success with stent placement, adverse events, patient survival, duration of stent patency, and device performance were analyzed. RESULTS: Endoscopic biliary stenting was successful in all patients. No adverse events were encountered. The mean follow-up period of the 21 patients was 128 days (range, 3-263): 14 died of progressive disease at mean of 81 days (range, 3-210), 3 remain alive (at days 239, 250, and 263), and 4 were lost to follow-up (at days 90, 91, 92, and 116). The mean duration of stent patency was 249 days. Tumor ingrowth was observed in one patient (5%). Minor technical problems were encountered in 3 patients: 1 proximal deployment, 1 distal deployment, and difficulty associated with the delivery system in 1. CONCLUSIONS: The Za-metal stent provided effective palliation for patients with inoperable malignant biliary tumors. Although minor technical problems were encountered with stent deployment, the overall stent patency, efficacy, and safety profile appear satisfactory.     

A prospective randomized trial of Tannenbaum-type Teflon-coated stents versus polyethylene stents for distal malignant biliary obstruction

OBJECTIVE: Stent clogging is a major limitation in the palliative treatment of malignant biliary obstruction. Preliminary studies suggested improved duration of patency of a Tannenbaum design stent with a stainless steel mesh and an inner Teflon coating (TTC). We compared the patency of a TTC stent with a conventional polyethylene (PE) stent in a prospective randomized trial. METHODS: Between February 1998 and September 1998 we included 60 patients with distal malignant bile duct obstruction. Diagnosis included carcinoma of the pancreas (n = 57) and ampullary cancer (n = 3). There were 29 men and 31 women with a median age of 77 years. Stent diameter (10 Fr) and length (11 cm) were similar but both stent design and material were different: a Tannenbaum design stent with a stainless steel mesh and an inner Teflon coating, and an Amsterdam-type PE stent. RESULTS: Sixty patients were evaluated; 30 in the TTC group and 30 in the PE group. Early complications occurred in two patients in each group. Stent dysfunction occurred in 18 of TTC stents and 12 of PE stents. Median stent patency was 102 days for TTC and 142 days for PE stents (P = 0.41). Median survival did not differ significantly for both treatment groups (TTC, 121 days; PE, 105 days). Stent migration, in all cases proximal into the common bile duct, occurred in four patients in the TTC group versus zero in the PE group (P = 0.038). CONCLUSIONS: This study did not confirm improved patency of Tannenbaum-type Teflon-coated stents. Proximal migration prompts for additional design modifications.     

Endoscopic management of occluded biliary Wallstents: a cancer center experience

BACKGROUND: Biliary obstruction caused by unresectable malignancy commonly is treated by placement of a biliary self-expandable metallic stent. The endoscopic and percutaneous techniques for self-expandable metallic stent placement are well established and can be performed with a high success rate. Self-expandable metallic stent placement affords palliation of pruritus and enables treatment of advanced cancer with chemotherapeutic agents metabolized by the liver. Unfortunately, these stents tend to occlude with time. Optimal management of an occluded self-expandable metallic stent remains to be determined. METHODS: A retrospective review was undertaken to determine optimal management of the occluded self-expandable metallic stent. Patients with malignant biliary obstruction who had endoscopic management for occluded Wallstents that had been placed percutaneously and endoscopically were studied. All patients underwent ERCP with one of the following interventions: mechanical cleaning, insertion of a plastic stent within the Wallstent, or insertion of a second Wallstent. The effectiveness of the intervention and duration of stent patency thereafter was studied. RESULTS: A total of 34 patients with occluded biliary Wallstents underwent the following procedures: mechanical cleaning (6 patients), placement of a second Wallstent (4), or insertion of a plastic stent (24). Mechanical cleaning was effective in only one of 6 patients. For all 4 patients who underwent placement of a second Wallstent, there was resolution of jaundice or cholangitis and no reocclusion. Plastic stent insertion was successful in 22 of 24 patients. Median duration of stent patency after intervention was 192 days (range 81-257 days) after second Wallstent placement, 90 days (11-393 days) after plastic stent insertion, and 21 days (3-263 days) after mechanical cleaning. Duration of stent patency was better when the initial malignant stricture involved the distal vs. the proximal bile duct. CONCLUSIONS: Occlusion of a biliary Wallstent is best managed by endoscopic insertion of a second Wallstent or a plastic stent. Mechanical cleaning is less effective. The level of the initial biliary obstruction influences stent patency.     

Human application of a metallic stent covered with a paclitaxel-incorporated membrane for malignant biliary obstruction: multicenter pilot study

BACKGROUND: Paclitaxel, with its antitumor effect, may improve the function of metallic stents used for biliary drainage. However, clinical studies that use metallic stents covered with a paclitaxel-incorporated membrane (MSCPM) in the biliary tract of human beings have not been previously carried out. OBJECTIVE: To evaluate the safety and efficacy of an MSCPM for patients with malignant biliary obstruction. DESIGN AND SETTING: A case series that includes 4 endoscopy centers. PATIENTS: From July 2003 to August 2006, a total of 21 patients diagnosed with unresectable malignant biliary obstruction. INTERVENTION: Endoscopic placement of an MSCPM. MAIN OUTCOME MEASUREMENTS: Stent occlusion, complications, stent patency, patient survival, and the periodic mean concentration of paclitaxel in the blood. RESULTS: Occlusion of the MSCPM was observed in 9 patients and was caused by bile sludge or clog in 4, tumor overgrowth in 3, and tumor ingrowth in 2. Complications included obstructive jaundice in 6, cholangitis in 3, and 1 patient showed stent migration with cholecystitis. The mean patency of a MSCPM was 429 days (median 270 days, range 68-810 days) and cumulative patency rates at 3, 6, and 12 months were 100%, 71%, and 36%, respectively. The mean survival of patients was 350 days (median 281 days, range 68-811 days). The highest concentration of paclitaxel in the blood was found between 1 and 10 days after insertion. LIMITATIONS: Small number of patients and low rate of pathologic diagnosis. CONCLUSIONS: The endoscopic insertion of MSCPM is technically feasible, safe, and effective in patients with malignant biliary obstruction. In addition, MSCPM may exert local antitumor activity because of the steady release of paclitaxel.     

SINGLE‐SESSION ENDOSCOPIC BILATERAL Y‐CONFIGURED PLACEMENT OF METAL STENTS FOR HILAR MALIGNANT BILIARY OBSTRUCTION

Background: The aim of this study was to evaluate the efficacy and safety of endoscopic bilateral biliary metal stent placement for hilar malignant obstruction. Patients and Methods: Twenty patients with unresectable malignant hilar biliary obstruction who had undergone endoscopic bilateral Y‐configured biliary drainage with metal stents were enrolled as a study group (YMS group). Thirty‐seven patients who had undergone bilateral drainage with plastic stents were selected as a historical control (PS group). Two newly designed metal stents for bilateral Y‐configured placement were endoscopically deployed in a partial stent‐in‐stent manner in one session. Technical success, early complications, and stent patency were evaluated. Results: The technical success rate in the YMS group was 100%. Mild post‐endoscopic retrograde cholangiopancreatography pancreatitis occurred in one patient in the YMS group and in two in the PS group. The success rate of biliary decompression was 95% in the YMS group and 89% in the PS group (P = 0.65). During a median follow‐up period of 7.3 months, the incidence of stent occlusion in the YMS group was significantly lower than that in the PS group (30% vs 62%, P = 0.028). Mean stent patency in the YMS group was 250 days and that in the PS group was 115 days (P = 0.0061). Risk factors for stent occlusion were bile duct cancer (P = 0.035) and the PS group (P = 0.07) by multivariate analysis. Conclusion: Single‐session endoscopic bilateral biliary placement of newly designed metal stents for hilar malignant obstruction is safe and useful with a high technical success rate and a long patency period.     

放置金属支架姑息性解除恶性胆道梗阻57例

目的内镜法放置胆道支架,姑息性治疗胆管恶性梗阻的最大缺陷是支架的阻塞,造成阻塞的重要原因之一是通常的塑料支架口径较小,而放置可膨式金属支架使得内引流中口径达到1cm.方法我们从1994年4月-1996年5月放置膨胀式金属道支架治疗57例无法根治的恶性梗阻性黄疸患者,其中采用内镜法置管54例,经皮肝穿刺法3例.结果导丝定位后支架放置的成功率为95%,2例发生胆管炎,经保守治疗得以控制.术后两周内黄疸完全消退21例,明显减退23例,然而9例患者在平均147d 后由于引流失效出现晚期胆管炎.全组有23例术前采用鼻胆管和3例采用内置管临时性引流,临时性引流具有可预先了解引流效果和控制炎症的优点.结论对于无法切除的恶性胆道梗阻患者,放置金属胆道支架可有效解除黄疸,改善生活质量,但欲获得最佳疗效,需严格掌握置管指证.为获得持久的引流效果.肿瘤两端支架的长度不宜短于2cm;对肝门部胆管癌,Bismuth 分型对挑选合适的引流部位有较大的参考价值.     

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

BackgroundBiliary 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.AimsTo assess efficacy and safety of the ComVi partially covered self-expandable metal stents as primary palliative treatment of distal malignant biliary obstruction.MethodsSeventy 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.ResultsOverall 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%).ConclusionsThe 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.     

A prospective trial of a new self-expanding plastic stent for malignant esophageal obstruction

OBJECTIVE: We studied a new expandable plastic stent in the palliation of malignant esophageal obstruction. METHODS: Eight patients with malignant esophageal obstruction and dysphagia were studied. An expandable covered plastic stent made of polyester netting and covered with a silicone membrane was inserted and released into the stenosis. Relief of dysphagia and functional status were measured. RESULTS: The stent was successfully inserted in all eight patients. The median dysphagia score dropped from 3 (able to eat liquids only) to 1 (some dysphagia with solid food), and seven of the eight patients had an improvement of at least two grades of dysphagia. Mean survival was 87 days (range 17-226). Stent migration occurred in one patient after 50 days; stent occlusion due to tumor ingrowth was not seen. CONCLUSIONS: A low cost (approximately $400) expandable plastic stent has been developed that is safe and effective in the palliation of malignant esophageal obstruction. Large randomized trials comparing this stent to expandable metal stents are warranted.     

COVERED WALLSTENT FOR PALLIATION OF MALIGNANT COMMON BILE DUCT STRICTURE: PROSPECTIVE MULTICENTER EVALUATION

Background: Occlusion due to tumor ingrowth is a major drawback in self‐expandable metallic stents. Covering the stent is a probable solution to prevent tumor ingrowth. A manufactured covered self‐expandable metallic stent, Covered Wallstent, has become commercially available. We evaluated the Covered Wallstent in a prospective uncontrolled multicenter setting. Methods: Between October 2001 and October 2003, 97 patients with common bile duct strictures deemed unfit for surgical resection underwent placement of a single Covered Wallstent, and were followed prospectively until April 2004. Results: Placement of the stent was successful in all the patients attempted. As a procedure‐related complication, acute pancreatitis developed in four patients, in one of whom obstruction of the pancreatic duct orifice with the stent body seemed to be a major cause. The 30‐day mortality was 9.3% (nine patients). Stent occlusion occurred in 22 patients as a late (greater than 30 days) complication, due to either tumor overgrowth (14 patients) or encrustation (eight patients). Distal migration of the stent was demonstrated in two other patients. No stent occlusions due to tumor ingrowth were observed. Patency rates of the stent for 3‐, 6‐, and 12‐month periods were, respectively, 90.7, 82.5, and 45.9%. Conclusions: The present results in a large series suggest that placement of the Covered Wallstent is feasible and effective in the palliation of patients with malignant common bile duct strictures. The Covered Wallstent seems to be reliable in eliminating tumor ingrowth. The role of stent covering in promoting stent function should be examined in a prospective comparative study between covered‐ and uncovered Wallstents.