Prospective comparison of endoscopic bilateral stent-in-stent versus stent-by-stent deployment for inoperable advanced malignant hilar biliary stricture

Background and Aims: Although the efficacy of palliative bilateral biliary drainage using self-expandable metal stents has been demonstrated, it is unclear which bilateral method is optimal for advanced malignant hilar biliary strictures (MHSs). This pilot study compared bilateral stent-in-stent (SIS) with stent-by-stent (SBS) deployment for advanced MHSs. Methods: Patients with inoperable high-grade MHSs were enrolled in this prospective randomized multicenter study. The primary outcome was the rate of adverse events, whereas secondary outcomes were technical and clinical success, reintervention, therapeutic outcomes, stent patency, and survival duration. Results: This study randomized 69 of 74 pathologically diagnosed patients to the SIS (n = 34) or SBS (n = 35) groups. The total adverse event rate after stent deployment did not differ between the 2 groups (23.5% in the SIS group vs 28.6% in the SBS group, P = .633). The primary technical success rate was 100% (34/34) and 91.4% (32/35) in the SIS and SBS groups, respectively (P = .081). The clinical success rate was 94.1% (32/34) and 90.6% (29/32), respectively (P = .668). The stent patency rate at 3 months was 85.3% in the SIS group and 65.7% in the SBS group (P = .059). At 6 months, the stent patency rate was 47.1% and 31.4%, respectively (P = .184). The median cumulative stent patency and survival probability did not differ between the 2 groups. Conclusions: Efficacy of bilateral SIS and SBS deployment may be similar in terms of total adverse events, technical and clinical success, stent patency, and survival. The stent patency rates at 3 and 6 months was higher in the SIS group without statistical difference.