Efficacy of Partial Covered Double Bare Metal Stent Compared to Uncovered Double Bare Metal Stent in Malignant Biliary Obstruction

Study Overview
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Brief Summary
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Previous studies indicated that covered stents are less likely to become occluded in comparison to bare stents. While the probability of occlusions caused by tumor in-growth is less in covered stents, they are more likely to spontaneously migrate to a position that is distal to the original deployment site. However, newer covered stents with improved designs, such as the partially covered double bare metallic stent used for this study, include features to mitigate the migration issue. The purpose of this study is to confirm whether the difference in patency rate between regular covered stents and bare stents, which has already been well established by existing studies, is also reproducible when double covered stents are compared against double bare stents.

Detailed Description
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Malignant obstructive jaundice is a common complication of advanced stage cholangiocarcinoma, GB cancer, and pancreatic cancer. In biliary stricture by malignancy, biliary drainage with placement of self-expanding metal stent (SEMS) for palliation is the therapy of choice in these patients. When compared to plastic stents, SEMS present a significantly decreased risk of recurrent biliary obstruction. SEMS are also more cost-effective than plastic stents in patients with a life expectancy of longer than 4 months. However, despite their numerous benefits, SEMS become occluded in up to 50 % of patients in the first 6-8 months. In order to minimize the occurrence of this issue, covered stents were developed. Previous studies indicated that covered stents are less likely to become occluded in comparison to bare stents. While the probability of occlusions caused by tumor in-growth is less in covered stents, they are more likely to spontaneously migrate to a position that is distal to the original deployment site. However, newer covered stents with improved designs, such as the partially covered double bare metallic stent used for this study, include features to mitigate the migration issue. The purpose of this study is to confirm whether the difference in patency rate between regular covered stents and bare stents, which has already been well established by existing studies, is also reproducible when double covered stents are compared against double bare stents.

Official Title
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Efficacy of Partial Covered Double Bare Metal Stent Compared to Uncovered Double Bare Metal Stent in Malignant Biliary Obstruction: A Multicenter Prospective Randomized Trial

Conditions
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Malignant Tumor

Intervention / Treatment
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* Device: SEMS(self-expandable metallic stent)
* Device: Stenting by ERCP (endoscopic retrograde cholangiopancreatography)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pathologically confirmed malignant biliary obstruction or clinically defined malignant biliary obstruction malignant biliary obstruction was located more than 1cm from the hilum older than 20 years old Life expectancy > 6 months Inoperable case due to advanced stage or comorbidity Informed consent obtained Exclusion Criteria: Inadequate case for ERCP Failed endoscopic approach to duodenum or biliary tract biliary obstruction was located at hilum or IHD patients with uncontrolled infection Pregnancy No signed informed consent

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: the intervention group<br>Partial covered double bare metal stent | Device: SEMS(self-expandable metallic stent)<br>* Find the obstruction site by ERCP(endoscopic retrograde cholangiopancreatography) and insertion the SEMS(self-expandable metallic stent) through duodenal endoscopy. Metal stents are inserted to ensure adequate decompression and bile drainage. The diameter and stent lengths can be changed according to the lesion.<br>* Other names: Obstructive jaundice decompression with endoscopic metal stenting;|
| Active Comparator: the control group<br>Uncovered double bare metal stent | Device: Stenting by ERCP (endoscopic retrograde cholangiopancreatography)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean duration of stent patency | Check the duration until the date of obstruction of inserted stent within 6 months after stenting | 6 months after stenting | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patency rate of stent |  | 6 months after stenting | 
| Overall survival |  | 6 months after stenting |