Comparison Between Transpapillary and Suprapapillary Metal Stent

Study Overview
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Brief Summary
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If surgical treatment is not possible in patients with malignant obstruction in the common bile duct, placing metal stents using endoscopy is a standardized treatment to resolve biliary obstruction. The metal stent is located in the bile duct to cover the stenotic portion by malignant tumors. The lower end of the metal stent can be located inside the common bile duct above the major ampulla or in the duodenum through the major ampulla. These two procedures with supra- or trans-papillary stents are currently being performed in general clinical practices, depending on the preference of the endoscopists. Until now, the comparison of the clinical results of the two procedures has been scarcely studied, and there is no prospective study yet. Therefore, researchers aim to compare the clinical results of two stent procedures through prospective randomized controlled studies.

Detailed Description
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If surgical treatment is not possible in patients with malignant obstruction in the common bile duct, endoscopic metal stent placement to resolve biliary obstruction is a standard treatment that is commonly performed. The metal stents relieve the bile duct stenosis by malignant tumors, helping to drain the bile and improving jaundice. There is no doubt that the center of the metal stent is located in the central part of the biliary stricture, but the location of the lower end of the metal stent is not fixed. The lower end of the metal stent can be located in two main locations, either in the common bile duct above the major ampulla or in the duodenum through the major ampulla. These procedures with supra- or trans-papillary stents are performed in common and are determined by the operator's preference. According to several retrospective studies so far, trans-papillary metal stents were effective in improving the initial biliary obstruction, but there was no difference in their long-term effects. Mao et al. showed that trans-papillary metal stents increase jaundice-free survival, and Shin et al. revealed the advantages of trans-papillary metal stents because they had a high success rate of secondary endoscopic procedures. On the contrary, Okamoto et al. showed that acute cholangitis more developed after trans-papillary metal stents placement, while Joe et al. revealed the advantages of supra-papillary metal stents because they reduce acute pancreatitis after the procedures. It has not yet been determined which method is effective. So far studies are all retrospective, and some of them placed the metal stents in a percutaneous way rather than endoscopy without sphincterotomy. Besides, some studies included intra-hepatic or hilar bile duct strictures, making it difficult to interpret the results. Therefore, through a prospective randomized controlled study, the researchers want to compare the clinical results of supra- and trans-papillary metal stents placed by endoscopes in malignant common bile duct obstruction.

Official Title
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Comparison Between Transpapillary and Suprapapillary Metal Stent Placement With Endoscopic Sphincterotomy in Common Bile Duct Malignant Obstruction: Prospective Randomized Controlled Study

Conditions
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Common Bile Duct Stricture

Intervention / Treatment
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* Procedure: Metal stent placement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with common bile duct obstruction due to malignancy Exclusion Criteria: intrahepatic or perihilar bile duct obstruction (except Klatskin type I) patients who have operability or want surgery strictures located within 2 cm from the end of distal common bile duct patients who are not able to undergo endoscopy due to cardiovascular or pulmonary diseases patients whose informed consents are not received patients in whom an endoscope can not access to the ampulla due to anatomical deformity by previous surgery

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
Interventional Model Description: supra-papillary metal stent group trans-papillary metal stent group
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: supra-papillary metal stent group<br>The distal ends of metal stents are located above the major papilla in the common bile duct. | Procedure: Metal stent placement<br>* Non-covered biliary metal stents are placed by endoscopy. The distal ends of metal stents are located above the major ampulla in the common bile duct or below the major ampulla in the duodenum.<br>|
| Active Comparator: trans-papillary metal stent group<br>The distal ends of metal stents are located below the major papilla in the duodenum. | Procedure: Metal stent placement<br>* Non-covered biliary metal stents are placed by endoscopy. The distal ends of metal stents are located above the major ampulla in the common bile duct or below the major ampulla in the duodenum.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stent function maintenance duration | jaundice free survival | through study completion, an average of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| stone or sludge occurrence | in-stent or above stent bile duct stone formation | through study completion, an average of 1 year | 
| in-stent stenosis or tumor overgrowth | stenosis due to tumor growth: in-stent or over the stent | through study completion, an average of 1 year | 
| acute cholangitis occurrence | after procedure acute cholangitis occurrence rate | through study completion, an average of 1 year | 
| stent migration rate | spontaneous migration rate | through study completion, an average of 1 year | 
| overall survival | duration between stent placement and death | From date of randomization until the date of date of death from any cause, assessed up to 36 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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metal stent, common bile duct obstruction, endoscopic retrograde cholangiopancreatography