Side-by-side versus stent-in-stent deployment in bilateral endoscopic metal stenting for malignant hilar biliary...

The clinical differences between side-by-side and stent-in-stent deployment using a self-expanding metal stent for hilar malignant obstruction have not been evaluated.

The purpose of this study was to compare the clinical features between side-by-side and stent-in-stent deployment.

We compared side-by-side and stent-in-stent deployment in 52 consecutive patients with malignant hilar biliary obstruction who underwent endoscopic bilateral drainage using self-expanding metal stent. Side-by-side deployment (SBS group) was performed in 28 patients from 2002 to 2005, and stent-in-stent deployment (SIS group) in 24 patients from 2006 to 2010. Technical success, functional success, complications, stent occlusion and cumulative stent patency in the SBS and SIS groups were evaluated and compared retrospectively.

There were no significant inter-group differences in technical success (SBS vs. SIS, 89 vs. 100 %, respectively), functional success (96 vs. 100 %), early complications (11 vs. 4 %), late complications (32 vs. 8 %) or stent occlusion (20 vs. 42 %). The incidence of complications was significantly higher for SBS than for SIS (44 vs. 13 %; p = 0.016). Cumulative stent patency was significantly better for SBS than for SIS (log-rank, p = 0.047). SBS was not associated with significantly longer cumulative stent patency in univariate Cox proportional hazard analysis (HR 0.35; 95 % CI 0.12-1.03; p = 0.056) and multivariate analysis (HR 0.39; 95 % CI 0.13-1.16; p = 0.090).

The incidence of complications is higher for side-by-side than stent-in stent deployment in bilateral metal stenting. In terms of cumulative stent patency, side-by-side deployment tends to be more effective than stent-in-stent deployment.