Malignant bile-duct obstruction: experience with self-expanding metal endoprostheses (Wallstents) in Austria

Risk Factors for Early- and Late-Onset Cholecystitis after Y-Configured Metal Stent Placement in Patients with Malignant Hilar Biliary Obstruction: A Single-Center Study

This study evaluated the prevalence and risk factors of early- (within 7 days of placement) and late-onset (after 7 days of placement) cholecystitis after Y-configured metal stent placement. Between June 2005 and August 2020, 109 patients who had been treated with Y-configured metal stents for malignant hilar obstruction were enrolled in the study. We retrospectively analyzed the potential risk factors for post-stent cholecystitis. The presence of diabetes (p = 0.042), the length of the common part of the Y-stent (p = 0.017), filling of the gallbladder with contrast medium during the procedure (p = 0.040), and tumor invasion of the cystic duct accompanied by filling the gallbladder with contrast medium during metal stent placement (p = 0.001) were identified as important risk factors. In cases of late-onset cholecystitis, stent obstruction (p = 0.004) and repeated endoscopic procedures due to stent malfunction (p = 0.024) were significant risk factors. In the multivariate logistic regression analysis, significant risk factors were the length of the common part of the Y-stent (p = 0.032) in early-onset cholecystitis and stent obstruction (p = 0.007) in late-onset cholecystitis. This study demonstrated that early-onset cholecystitis may occur in patients according to the length of the common portion of the Y-stent. In contrast, late-onset cholecystitis may occur in patients with stent obstruction.

Comparative Study on Nosocomial Biliary Tract Infection Rate Between Biliary Stent Loaded with Radioactive 125 I Seeds and Conventional Biliary Stent in the Treatment of Distal Malignant Biliary Obstruction

BACKGROUND

The purpose of this prospective randomized study was to compare the nosocomial biliary tract infection rate of biliary stent implantation with a biliary stent loaded with radioactive 125 I seeds (radioactive biliary stent, RBS) and conventional biliary stent (CBS); additionally, to preliminary discuss the causes of postoperative cholangitis. Moreover, the results will provide clinical evidence for the prevention of postoperative biliary tract infection.

MATERIALS AND METHODS

We prospectively analyzed the nosocomial infection rate of the distal malignant biliary obstruction (MBO) treatment by stent implantation with RBS and CBS. All MBO patients who initially visited our tertiary hospital between July 2015 and December 2019 (n= 196) were evaluated, enrolled, and randomly divided into 2 groups, RBS (n=97) and CBS (n=99) group. χ 2 test was used to evaluate the categorical data, and t test was used to evaluate the numerical data.

RESULTS

Our analysis of the study showed the incidence of postoperative infections of a biliary tract of the RBS group (23.7%) was significantly higher than the CBS group (11.1%). The difference was statistically significant (χ 2 =5.425, P =0.020). Our study also showed the most common pathogenic bacteria after surgery was Escherichia coli (26.5%).

CONCLUSION

Treatment for distal MBO with biliary stent loaded with radioactive 125 I seeds had a higher nosocomial infection rate, and the most common pathogenic bacteria was E coli. , Supplemental Digital Content 1, http://links.lww.com/sle/A350.

Percutaneous transhepatic biliary stent placement in the palliative management of malignant obstructive jaundice: initial experience in a tertiary center in Ghana

Introduction

one of the mainstays of management of malignant biliary obstruction is the decompression of the biliary system and its associated obstructive symptoms. Non-surgical palliative treatment such as percutaneous transhepatic biliary stenting is desirable in many selected patients. However, this service is often not available in many resource-limited countries. We share our initial experience of percutaneous transhepatic biliary stenting for the management of malignant biliary obstruction in our first set of patients with surgically non resectable malignant biliary obstruction in Ghana.

Methods

percutaneous transhepatic biliary stenting was performed on the first 23 consecutive patients at the Korle Bu Teaching Hospital. The procedure served as the first palliation for malignant obstruction through interventional radiology. Medical records as well as serum levels of total bilirubin (TBil), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were used to assess the efficiency of the intervention. Microsoft Excel 2010 was used to analysis the data.

Results

most patients had resolution of jaundice with marked improvement in liver function and resolution of the itching associated with obstructive jaundice. During the follow-up of cases, one major complication of hemoperitoneum occurred requiring laparotomy. No other major complications such as bile leakage or death occurred. Four (4) patients had sepsis, which was managed.

Conclusion

the introduction of the intervention in Ghana has proven to valuable for palliative drainage and relief of obstructive symptoms, hence contributing to better patient management. It is relatively safe with minor complications among Ghanaians with non-resectable obstructive symptoms.

Management of acute cholecystitis after biliary stenting for malignant obstruction: comparison of percutaneous gallbladder drainage and aspiration

PURPOSE

To evaluate and compare the clinical outcomes between percutaneous gallbladder drainage (PGBD) and percutaneous gallbladder aspiration (PGBA) for acute cholecystitis after biliary stenting for malignant biliary obstruction.

MATERIALS AND METHODS

Twenty-six and 14 patients underwent PGBD and PGBA, respectively, for acute cholecystitis after biliary stenting for malignant obstruction. The technical success rate, clinical effectiveness, and safety were compared between the 2 groups.

RESULTS

Technical success was achieved in all patients. Clinical effectiveness rate was significantly higher in the PGBD group than in the PGBA group [100% (26/26) vs. 57% (8/14), p < 0.01]. In the PGBA group, clinical effectiveness rate was significantly lower in patients with tumor involvement of the cystic duct [13% (1/8) with involvement vs. 83% (5/6) without involvement, p = 0.03]. There were no deaths related to the procedure or acute cholecystitis aggravation. Pleural effusion and biliary peritonitis occurred in 1 patient each after PGBD and intra-abdominal bleeding occurred in 1 patient after PGBA as complications requiring treatment.

CONCLUSION

Although PGBD was a more effective treatment for acute cholecystitis after biliary stenting for malignant obstruction, PGBA may be a less invasive option for high-risk patients without tumor involvement of the cystic duct.

Risk Prediction for Early Biliary Infection after Percutaneous Transhepatic Biliary Stent Placement in Malignant Biliary Obstruction

PURPOSE

To establish a nomogram for predicting the occurrence of early biliary infection (EBI) after percutaneous transhepatic biliary stent (PTBS) placement in malignant biliary obstruction (MBO).

MATERIALS AND METHODS

In this multicenter study, patients treated with PTBS for MBO were allocated to a training cohort or a validation cohort. The independent risk factors for EBI selected by multivariate analyses in the training cohort were used to develop a predictive nomogram. An artificial neural network was applied to assess the importance of these factors in predicting EBI. The predictive accuracy of this nomogram was determined by concordance index (c-index) and a calibration plot, both internally and externally.

RESULTS

A total of 243 patients (training cohort: n = 182; validation cohort: n = 61) were included in this study. The independent risk factors were length of obstruction (odds ratio [OR], 1.061; 95% confidence interval [CI], 1.013-1.111; P = .012), diabetes (OR, 5.070; 95% CI, 1.917-13.412; P = .001), location of obstruction (OR, 2.283; 95% CI, 1.012-5.149; P = .047), and previous surgical or endoscopic intervention (OR, 3.968; 95% CI, 1.709-9.217; P = .001), which were selected into the nomogram. The c-index values showed good predictive performance in the training and validation cohorts (0.792 and 0.802, respectively). The optimum cutoff value of risk was 0.25.

CONCLUSIONS

The nomogram can facilitate the early and accurate prediction of EBI in patients with MBO who underwent PTBS. Patients with high risk (> 0.25) should be administered more effective prophylactic antibiotics and undergo closer monitoring.

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.

A comparison of uncovered metal stents for the palliation of patients with malignant biliary obstruction: nitinol vs. stainless steel

BACKGROUND

Various types of self-expandable metal stents have been introduced for the palliation of malignant biliary obstruction.

AIMS

To compare the outcomes of WallFlex™ and Wallstent™ uncovered biliary self-expandable metal stents (SEMSs) for the palliation of patients with malignant biliary obstruction.

METHODS

Between October 2008 and December 2009, all SEMSs placed for malignant biliary obstruction were WallFlex™: all patients palliated were included in the study. Before October 2008, all the SEMSs placed for malignant biliary obstruction were Wallstent™, and the patients palliated from July 2007 to September 2008 were the comparative group.

RESULTS

A total of 58 WallFlex™ and 54 Wallstent™ SEMSs were placed, and efficacious biliary decompression was achieved in all patients. Early complications occurred in 5 patients in the WallFlex™ group and in 3 in the Wallstent™ group (p=ns). Late complications occurred in 6 patients in the WallFlex™ group and in 16 in the Wallstent™ group (p<0.01). The overall patency of the self-expandable metal stent in the WallFlex™ and the Wallstent™ groups was similar (227 days vs. 215 days, p=ns). Mean patient survival was 242 days in the WallFlex™ group and 257 days in the Wallstent™ group (p=ns).

CONCLUSIONS

We found no difference in terms of overall patency between the two types of SEMSs, but there was an increased rate of late adverse events in the Wallstent™ group.

Usefulness of slimmer and open-cell-design stents for endoscopic bilateral stenting and endoscopic revision in patients with hilar cholangiocarcinoma (with video)

BACKGROUND

Although endoscopic bilateral metal stenting using a "stent-in-stent" method is currently used to treat patients with unresectable hilar cholangiocarcinoma, this method has limited application in cases of tight strictures or endoscopic revision in case of tumor recurrence, especially on the first stent (initial Y stent placed) side.

OBJECTIVE

To evaluate the clinical efficacy of bilateral metal stenting with the use of a slimmer (7F), open-cell-design stent.

DESIGN

Prospective, uncontrolled, single center.

SETTING

Tertiary referral university hospital.

PATIENTS

This study involved 34 patients with unresectable hilar cholangiocarcinoma (Bismuth type II-IV).

INTERVENTION

Endoscopic bilateral metal stenting using a stent-in-stent method was performed. First, a Y stent with a central, wide-open mesh was inserted, then a Zilver stent, with a preloaded delivery system that is slimmer (7F) than those (7.5-8.5F) of conventional stents, was placed into the contralateral hepatic duct through the central portion of the Y stent. The Zilver stent has an open-cell design, and it can be dilated easily. Thus, revision with bilateral plastic stents was tried in cases of stent obstruction.

MAIN OUTCOME MEASUREMENTS

Technical success, functional success, complications, and revision method.

RESULTS

Technical success (bilateral stenting using Y and Zilver stents) was achieved in 29 of 34 (85.3%) patients. Functional success was noted in 29 of the 29 (100.0%) patients who received bilateral stenting. Early complications such as pancreatitis and cholecystitis occurred in 3 (10.3%) patients. Late complications occurred in 11 (37.9%) patients. Cholecystitis, which occurred in 2 patients, was managed by percutaneous transhepatic gallbladder drainage. Stent obstruction by tumor ingrowth or overgrowth occurred in 9 of 29 (31.0%) patients. These patients were managed by placement of bilateral plastic stents (4 of 9), percutaneous transhepatic biliary drainage (4 of 9), and a combined method (1 of 9). Of the 5 patients in whom endoscopic revision was attempted, 4 (80%) were managed endoscopically with bilateral plastic stents.

LIMITATIONS

Small number of patients, uncontrolled study.

CONCLUSION

A slimmer (7F), open-cell-design stent is effective in endoscopic bilateral stenting for advanced hilar cholangiocarcinoma and endoscopic revision in case of tumor recurrence.

Chemical ablation of the gallbladder using alcohol in cholecystitis after palliative biliary stenting

Chemical ablation of the gallbladder is effective in patients at high risk of complications after surgery. Percutaneous gallbladder drainage is an effective treatment for cholecystitis; however, when the drain tube cannot be removed because of recurrent symptoms, retaining it can cause problems. An 82-year-old woman presented with cholecystitis and cholangitis caused by biliary stent occlusion and suspected tumor invasion of the cystic duct. We present successful chemical ablation of the gallbladder using pure alcohol, through a percutaneous gallbladder drainage tube, in a patient who developed intractable cholecystitis with obstruction of the cystic duct after receiving a biliary stent. Our results suggest that chemical ablation therapy is an effective alternative to surgical therapy for intractable cholecystitis.

Risk factors for cholecystitis after metal stent placement in malignant biliary obstruction

BACKGROUND

Cholecystitis related to metal stent placement is a morbid event.

OBJECTIVE

This study evaluated the risk factors of cholecystitis after metal stenting for malignant biliary obstruction.

PATIENTS

Between December 1997 and April 2003, 155 patients who were treated with a metal stent for malignant biliary obstruction were retrospectively enrolled.

MAIN OUTCOME MEASUREMENTS

The incidence and characteristics of patients with cholecystitis were evaluated and compared with those of patients without cholecystitis. Patient characteristics and tumor or procedure-related data were recorded for the following variables: sex, age, tumor and stent length, stent type (covered vs uncovered), cholangitis before ERCP, degree of gallbladder filling with contrast medium during ERCP, primary disease type (Klatskin vs others), presence of gallbladder stones, and the relationship of the cystic duct orifice to the location of the tumor (across vs others).

RESULTS

There were 15 (9.7%) patients diagnosed with cholecystitis after metal stent insertion. The onset of cholecystitis was on average 4.6 days (range 1 to 26) after the procedure. We found that an obstruction across the cystic duct orifice by tumor (P < .01, odds ratio 12.7) and the presence of gallbladder stone (P = .01, odds ratio 6.6) were positively related to the cholecystitis after metal stent insertion.

LIMITATIONS

The limitations of the study were the use of multiple types of stents and the retrospective design.

CONCLUSIONS

This study demonstrated that an obstruction across the cystic duct by tumor and the presence of gallbladder stone were risk factors for the development of cholecystitis after metal stent placement.

Palliative biliary stents for obstructing pancreatic carcinoma

BACKGROUND

Palliative endoscopic stents or surgical by-pass are often required for inoperable pancreatic carcinoma to relieve symptomatic obstruction of the distal biliary tree. The optimal method of intervention remains unknown.

OBJECTIVES

To compare surgery, metal endoscopic stents and plastic endoscopic stents in the relief of distal biliary obstruction in patients with inoperable pancreatic carcinoma.

SEARCH STRATEGY

We searched the databases of the Cochrane Upper Gastrointestinal and Pancreatic Group specialised register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CancerLit, Current Concepts Database and BIDS (September 2002 to September 2004). The searches were re-run in December 2005 and we are awaiting further details on two trials. Reference lists of articles and published abstracts from UEGW and DDW were hand-searched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing surgery to endoscopic stenting, endoscopic metal stents to plastic stents, and different types of endoscopic plastic and metal stents, used to relieve obstruction of the distal bile duct in patients with inoperable pancreatic carcinoma.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. Adverse effects information was collected from the trials.

MAIN RESULTS

Twenty-one trials involving 1,454 people were included. Based on meta-analysis, endoscopic stenting with plastic stents appears to be associated with a reduced risk of complications (RR 0.60, 95% CI 0.45 - 0.81), but with higher risk of recurrent biliary obstruction prior to death (RR 18.59, 95% CI 5.33 - 64.86) when compared with surgery. There was a trend towards higher 30-day mortality in the surgical group (p=0.07, RR 0.58, 95% CI 0.32, 1.04). There was no evidence of a difference in technical or therapeutic success. Other outcomes were not suitable for meta-analysis. No trials comparing endoscopic metal stents to surgery were identified. In endoscopic stent comparisons, metal biliary stents appear to have a lower risk of recurrent biliary obstruction than plastic stents (RR 0.52, 95% CI 0.39 - 0.69). There was no significant statistical difference in technical success, therapeutic success, complications or 30-day mortality using meta-analysis. A narrative review of studies of the cost-effectiveness of metal stents drew conflicting conclusions, but results may be dependent on the patients' length of survival.Neither Teflon, hydrourethane, or hydrophilic coating appear to improve the patency of plastic stents above polyethylene in the trials reviewed. Only perflouro alkoxy plastic stents had superior outcome to polyethylene stents in one trial. The single eligible trial comparing types of metal stents reported higher patency with covered stents, but also a higher risk of complications. These results are based on review of the trials individual results only.

AUTHORS' CONCLUSIONS

Endoscopic metal stents are the intervention of choice at present in patients with malignant distal obstructive jaundice due to pancreatic carcinoma. In patients with short predicted survival, their patency benefits over plastic stents may not be realised. Further RCTs are needed to determine the optimal stent type for these patients.

Palliative biliary stents for obstructing pancreatic carcinoma

BACKGROUND

Palliative endoscopic stents or surgical by-pass are often required for inoperable pancreatic carcinoma to relieve symptomatic obstruction of the distal biliary tree. The optimal method of intervention remains unknown.

OBJECTIVES

To compare surgery, metal endoscopic stents and plastic endoscopic stents in the relief of distal biliary obstruction in patients with inoperable pancreatic carcinoma.

SEARCH STRATEGY

We searched the databases of the Cochrane Upper Gastrointestinal and Pancreatic Group specialised register, Cochrane Central Register of Controlled Trials , MEDLINE, EMBASE, CancerLit, Current Concepts Database and BIDS (September 2002 to September 2004). Reference lists of articles and published abstracts from UEGW and DDW were hand-searched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing surgery to endoscopic stenting, endoscopic metal stents to plastic stents, and different types of endoscopic plastic and metal stents, used to relieve obstruction of the distal bile duct in patients with inoperable pancreatic carcinoma.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. Adverse effects information was collected from the trials.

MAIN RESULTS

Twenty-one trials involving 1,454 people were included. Based on meta-analysis, endoscopic stenting with plastic stents appears to be associated with a reduced risk of complications (RR 0.60, 95% CI 0.45 - 0.81), but with higher risk of recurrent biliary obstruction prior to death (RR 18.59, 95% CI 5.33 - 64.86) when compared with surgery. There was a trend towards higher 30-day mortality in the surgical group (p=0.07, RR 0.58, 95% CI 0.32, 1.04). There was no evidence of a difference in technical or therapeutic success. Other outcomes were not suitable for meta-analysis. No trials comparing endoscopic metal stents to surgery were identified. In endoscopic stent comparisons, metal biliary stents appear to have a lower risk of recurrent biliary obstruction than plastic stents (RR 0.52, 95% CI 0.39 - 0.69). There was no significant statistical difference in technical success, therapeutic success, complications or 30-day mortality using meta-analysis. A narrative review of studies of the cost-effectiveness of metal stents drew conflicting conclusions, but results may be dependent on the patients' length of survival. Neither Teflon, hydrourethane, or hydrophilic coating appear to improve the patency of plastic stents above polyethylene in the trials reviewed. Only perflouro alkoxy plastic stents had superior outcome to polyethylene stents in one trial. The single eligible trial comparing types of metal stents reported higher patency with covered stents, but also a higher risk of complications. These results are based on review of the trials individual results only.

AUTHORS' CONCLUSIONS

Endoscopic metal stents are the intervention of choice at present in patients with malignant distal obstructive jaundice due to pancreatic carcinoma. In patients with short predicted survival, their patency benefits over plastic stents may not be realised. Further RCTs are needed to determine the optimal stent type for these patients.

Endoscopic removal of malfunctioning biliary self-expandable metallic stents

BACKGROUND

Endoscopic removal of malfunctioning self-expandable metallic biliary stents (SEMS) is difficult and not well described. The aim of this study is to review the indications, the techniques, and the results of SEMS removal in a cohort of patients with malfunctioning stents.

METHODS

All patients who underwent an attempt at endoscopic removal of biliary SEMS over a 5-year period were retrospectively identified. The main indications for SEMS removal were the following: distal migration of the stent or impaction to the duodenum, impaction into the bile-duct wall, tissue ingrowth, and inappropriate length of the stent causing occlusion of intrahepatic ducts. SEMS were removed by using foreign-body forceps or polypectomy snares.

RESULTS

Endoscopic removal of 39 SEMS (13 uncovered and 26 covered) was attempted in 29 patients (17 men; mean age, 66 years). SEMS extraction was attempted after a mean of 7.5 months (8.75 months standard deviation) post-SEMS insertion. Removal was successful in 20 patients (68.9%) and in 29 SEMS (74.3%). Covered SEMS were effectively removed more frequently than uncovered ones: 24 of 26 (92.3%) and 5 of 13 (38.4%), respectively (p < 0.05). No major complications were recorded. Multivariate analysis showed that the time interval between insertion and removal, SEMS length, stent-mesh design (zigzag vs. interlaced), and indication for removal were not predictive of success at stent removal.

CONCLUSIONS

Endoscopic removal of biliary SEMS is feasible and safe in more than 70% of cases. Because only 38% of uncovered SEMS were removable, the presence of a stent covering is the only factor predictive of successful stent extraction. The presence of diffuse and severe ingrowth was the main feature limiting SEMS removal.

Self-expandable metallic biliary stents with permanent access

OBJECTIVE

The objective of our study was to assess the safety and effectiveness of establishing a permanent access to self-expandable biliary stents in palliation of malignant biliary obstruction.

CONCLUSION

Permanent access to self-expandable biliary stent provided a safe and effective means for timely reintervention in stent occlusion with acceptable stent patency.

Percutaneous cystic duct stent placement for the treatment of acute cholecystitis resulting from common bile duct stent placement for malignant obstruction

Common bile duct (CBD) stent placement to relieve malignant biliary obstruction can occasionally cause cystic duct obstruction and acute cholecystitis. Cholecystostomy tube placement is often performed in patients with limited life expectancy but can have a significant impact on quality of life. To allow cholecystostomy tube removal, percutaneous metallic stent placement was performed across the cystic duct via the tube tract in such a patient. The procedure included traversal across the previously placed CBD stent. At 5-month follow-up, the patient remained symptom-free. In select patients who develop acute cholecystitis after CBD stent placement for malignant obstruction, percutaneous stent placement across the cystic duct may be considered a treatment option.

Open-biopsy-forceps technique for endoscopic removal of distally migrated and impacted biliary metallic stents

BACKGROUND

Endoscopic removal of distally migrated and impacted biliary metallic stents is technically challenging. An open-biopsy-forceps technique for endoscopic removal of these migrated stents is described.

METHODS

The technique was used in 4 patients with distally migrated and impacted covered metallic stents. A closed biopsy forceps was advanced through the stent mesh and opened within the stent to form an "anchor." With endoscope withdrawal, the stent was dislodged easily from the duodenum to the stomach. After grasping an end of the stent with a snare, the stent was removed by complete withdrawal of the endoscope.

OBSERVATIONS

In all patients, the impacted stent was removed successfully. Mean time for removal was 10.2 minutes. Although ulceration was evident in the duodenal wall where the distal stent end was impacted in all patients, no other complication or adverse event was observed.

CONCLUSIONS

The open-biopsy-forceps technique is useful for endoscopic removal of distally migrated and impacted biliary metallic stents.

Endoscopic treatment of pancreatico-biliary malignancies

Biliary obstructions, due to pancreatic cancer and cholangiocarcinoma, have an ominous prognosis. At the time of diagnosis, most patients are beyond any curative treatment. Palliative therapies, such as transhepatic biliary drainage, bypass surgery, and endoscopy, have an established role in the management of such patients. Endoscopic retrograde cholangio-pancreatography (ERCP) plays a key role, allowing diagnosis, collection of cytologic and bioptic specimens, and insertion of large-bore biliary stents. The major drawback of plastic stents is the high rate of clogging, requiring frequent stent exchange. In the 1990s, self-expanding metal stents (SEMS) were developed and randomized studies have shown their superiority over plastic stents. SEMS can be successfully used in patients with hilar tumors. Duodenal obstruction due to biliopancreatic neoplasms can also be managed endoscopically. ERCP can be performed on an outpatient basis in selected patients, reducing costs related to hospitalization. A team approach is mandatory to obtain the best results.

Polyurethane-covered Wallstents to recanalize Wallstents obstructed by tumor ingrowth from malignant common bile duct obstruction

Four patients with malignant obstruction of the common bile duct had been treated with uncovered Wallstents and suffered from a reobstruction after 2-13 months (mean 5.3 months). Repeat cholangiography revealed severe stenosis of the stent lumen caused by tumor ingrowth through the mesh. A Wallstent with a self-made polyurethane-cover was inserted through the uncovered stent in these patients. The four patients were followed for 3-13 months (mean 6.3 months) until death. There was good drainage with no evidence of recurrent obstruction in all patients. We conclude that a covered Wallstent may extend patency of stented bile ducts, preventing tumor ingrowth in patients with neoplastic obstruction. Further observations are needed.

A comparison of Ultraflex Diamond stents and Wallstents for palliation of distal malignant biliary strictures

OBJECTIVE

The objective of this study was to compare the effectiveness of the Ultraflex Diamond stent and the Wallstent for the drainage of distal malignant biliary strictures.

METHODS

The results obtained in 23 consecutive patients in whom the insertion of a Ultraflex Diamond stent had been attempted were compared with those obtained in 23 patients matched for age, gender, serum bilirubin, and diagnosis who had been treated with Wallstents.

RESULTS

Biliary drainage was obtained in 100% of cases. More than one stent was required in 4% and 12% of patients treated with Ultraflex Diamond stents and Wallstents, respectively (p > 0.05). The first stent inserted did not provide adequate biliary drainage in four patients, because of the impaction of the proximal end of Wallstents into the bile duct wall (n = 2) and obstruction of the stent lumen by tumor tissue (one in each group). Procedure-related morbidity and mortality were 4%. Patients were followed-up for a mean of 228 days (range, 1 to 1262 days). During follow-up, bile duct obstruction relapsed in 5/22 and 6/21 patients treated with Ultraflex Diamond stents and Wallstents, respectively. Life table analysis of bile duct patency was similar with both stent models.

CONCLUSIONS

Ultraflex Diamond stents are easy to insert and provide a high success rate of biliary drainage with minimal complication. Although long-term patency rates obtained with this stent were similar to those observed with Wallstents, no firm conclusion can be drawn in this regard due to the relatively small number of patients studied.

Interventional radiology and the use of metal stents in nonvascular clinical practice: a systematic overview

PURPOSE

The intent of this systematic overview was to describe the clinical role of metal stents in nonvascular health care interventions and the level of evidence supporting their use.

MATERIALS AND METHODS

Structured searches of Medline were conducted and limited to original peer-reviewed articles published in English.

RESULTS

Clinical practice involving metal stents was reported in more than 109 clinical series involving 4,753 patients. Stents were placed mainly for palliation of malignant biliary, esophageal, and airway obstruction in patients who were untreatable or had surgically unresectable lesions. Assessment of these interventions has so far centered on safety and technical success. Efficacy, quality of life, and costing factors were not routinely reported. Randomized trial evidence was available but limited; six randomized trials involving metal stents have been reported. Three trials involved biliary malignant obstruction, and all three reported metal stent (132 patients) palliation to be superior to plastic stent palliation (136 patients) based on longer patency and lower reintervention costs. Safety and complication differences between stents, however, were inconsistent across trials. In three trials involving esophageal malignant obstruction, metal stent (82 patients) palliation was reported to be superior to plastic stent (41 patients), based on lower complication and reintervention rates, and superior to laser therapy (18 patients), based on better dysphagia relief.

CONCLUSION

Use of metal stents has been reported for obstructed ducts and passageways of most body systems. There is, however, limited controlled trial evidence confirming the advantages of their use over plastic stents or other forms of treatment.