A Prospective, Randomized Multicenter Trial Comparing DoubleLayer and Polyethylene Stents for Malignant Distal Common Bile Duct Strictures

Background and Study Aims: Endoscopic biliary stenting is an established treatment for malignant obstructive jaundice. Stent clogging continues to be a major problem with plastic stents. The aim of this study was to carry out a prospective comparison of two stents with different materials and shapes: the Olympus DoubleLayer stent (DLS; perfluoro alkoxy, without sideholes) and the standard polyethylene (PE) stent (with sideholes). Patients and Methods: A total of 120 patients (70 women; mean age 71, range 36-91) with jaundice due to malignant strictures of the middle to distal third of the common bile duct were randomly assigned to receive either DLS (n = 60) or PE (n = 60) biliary stents. Patients with cholangitis, hemobilia, previous biliary drainage, hilar stricture, or ampullary cancer were excluded. Results: In all, 28 DLS patients (47%) and 17 PE stent patients (29%) died without clinical evidence of stent occlusion after a mean of 114 and 105 days, respectively (P<0.05). Twenty-six DLS patients (43 %) and 38 PE stent patients (63%) had symptoms of stent clogging after a mean of 144 and 99 days, respectively (P<0.05). Stent dysfunction (stent orifice impacted on the bile duct or duodenal wall, stent migration) was recorded in six DLS patients (10%) and five PE patients (8%) (n.s.). Kaplan-Meier analysis of DLS and PE stent clogging-free survival showed a significantly longer patency period with the DLS stents (P=0.0005) Conclusions: These results show that DoubleLayer stents have a longer patency period than PE stents. Patients who received PE stents had a higher risk of stent occlusion (relative risk 3.05; 95% CI, 1.57-5.89) before death than DLS patients.