Comparison of time to recurrent biliary obstruction between plastic stents and metallic stents for endoscopic ultrasound-guided biliary drainage

Endoscopic ultrasound-guided biliary drainage (EUS-BD) may prevent stent placement at the bile duct stricture. Therefore, whether a plastic stent (PS) or metallic stent (MS) should be used for EUS-BD remains to be undetermined. The present study aimed to clarify whether a PS or MS was more efficient for EUS-BD. Patients with malignant biliary obstruction who were successfully treated with EUS-BD were enrolled in the present study. The clinical characteristics, procedural outcomes and time to recurrent biliary obstruction (TRBO) were compared between patients treated with a PS (PS group) and patients treated with an MS (MS group). Consequently, 28 patients underwent PS placement and 11 patients underwent MS placement. In the PS group, 12 patients also underwent EUS-antegrade stenting (AGS) using an MS. The TRBO was not significantly different between the two groups (P=0.25). When the patients with AGS were excluded, the TRBO was significantly longer in the MS group than in the PS group (P=0.036). However, the TRBO was not significantly different between the patients in the MS group and those in the PS group who underwent AGS (P=0.61). In EUS-BD, MS is expected to be associated with a longer TRBO than PS. However, combining EUS-BD with AGS may help overcome the shorter TRBO associated with the use of PS.