Abstract

Introduction: Currently, by expert agreement, the diameter of metal biliary stents is 10 mm. New 12 mm diameter stents are now available. The aim of our study was to compare whether the patency of 12 mm diameter stents is better than that of conventional 10 mm diameter stents.

Methods: From April 2017 to April 2018, patients with biliary strictures were treated with metal biliary stents, covered or uncovered, 12 mm in diameter. Control patients treated with stents 10 mm in diameter were identified in our center database. The primary endpoint was time to RBO (recurrent biliary obstruction).

Results: We included 24 patients in the 12 mm group (62.5% male; mean age 71 years old) and 48 patients in the control group (64.6% male; mean age 68.8 years old). The median time to RBO was 5.9 months in the 12 mm group vs. 8.3 months in the 10 mm group (p=0.28). In the malignant stricture subgroup, RBO occurred after 6.1 months and 17.1 months in the 12 mm and 10 mm groups, respectively (p=0.06). The adverse event rate in the month following biliary stent placement was 25% (n=6/24) in the 12 mm group and 2% (n=1/48) in the control group.

Conclusion: This case control study did not show better patency of uncovered 12 mm diameter metal biliary stents in cases of malignant stenosis. The placement of covered 12 mm diameter stents in cases of benign strictures should be better evaluated.

Keywords: Biliary stent drainage; 12 mm diameter biliary stent; large diameter biliary stent