Randomized controlled exploratory study comparing the usefulness of two types of metallic stents with different axial forces for the management of duodenal obstruction caused by pancreatobiliary cancer

Abstract

Background: Very few studies have examined effectiveness of duodenal stent placement (DSP) for duodenal obstruction (DO) caused specifically by pancreatobiliary cancer. We compared two types of stents with different axial forces (AF) for DO with pancreatobiliary cancer.

Methods: The patients were randomly assigned to two stent groups with different AF (high AF stent, WallFlex™: W-group or low AF stent, Niti-S™: N-group). The primary endpoint was improvement in the Gastric Outlet Obstruction Scoring System (GOOSS) score. This study was registered at UMIN000009061.

Results: The GOOSS scores significantly improved in both W-group (0.9 before vs. 2.7 after; P = 0.002) and N-group (1.0 before vs. 2.5 after; P = 0.001). The change in the GOOSS score after DSP did not differ significantly between the groups (P = 0.482). The median time to recurrent DO (RDO) was significantly shorter in W-group than in N-group (89 days vs. 421 days; P = 0.025). The incidence of RDO was significantly higher in W-group than in N-group (64% vs. 24%; P = 0.027). Stent kinking occurred only in W-group.

Conclusions: The GOOSS scores significantly improved after DSP, but effectiveness did not differ significantly between groups. The use of stents with high AF was related to short-term stent patency, but did not influence survival time.

Keywords: Axial force; Duodenal stent placement; Gastric Outlet Obstruction Scoring System score; Pancreatobiliary cancer; Self-expandable metallic stent.