A prospective, randomized study of the patency period of the plastic antireflux biliary stent: an interim analysis.

Background: There is as yet no ideal design of a plastic biliary stent with the longest patency period.

Objective: To study the safety and effective patency period of a new plastic antireflux biliary stent in the clinical setting.

Design: We conducted a prospective, randomized trial to compare the patency of 2 similar plastic biliary stents, one of which has an antiduodenobiliary reflux property.

Setting: The study was conducted at 2 separate tertiary centers in 2 countries.

Patients: Patients with inoperable distal malignant biliary obstruction were recruited.

Interventions: One of the 2 types of plastic stents under study was randomly chosen and inserted in the common bile duct of the study subjects. The subjects were followed until the end of study or occlusion occurrence.

Main Outcome Measurements: Our primary endpoint was the time to stent occlusion in days, with stent-related adverse events and all-cause mortality the secondary endpoints.

Results: A total of 16 subjects were recruited for the study; 7 were allocated to group A (ordinary Tannenbaum stent) and 9 to group B (antireflux biliary stent). Five of 7 subjects (71%) in group B had stent occlusion within 8 days, and the primary end point was reached in all 7 subjects within 30 days, whereas the primary endpoint was not reached within 30 days in any of the subjects in group A. Our data showed a significantly shorter stent patency period in group B compared with group A (P < .003).

Limitations: Small sample size.

Conclusion: Routine use of antireflux plastic biliary stents in the palliative management of malignant biliary obstructions cannot be recommended at present. (Clinical trial registration number: NCT01142921.).