WallFlex® and Evolution® Duodenal Stents Have Similar Efficacy but Different Safety for Malignant Gastric Outlet Obstruction.

ABSTRACT

BACKGROUND: The WallFlex® and Evolution® stents are the most widely used duodenal stents, but no study has compared them. AIMS: We aimed to compare the efficacy and safety of WallFlex® and Evolution® stents for malignant gastric outlet obstruction. METHODS: We included all consecutive patients who were treated for malignant gastric outlet obstruction with WallFlex® or Evolution® self-expandable metal uncovered duodenal stents between 2013 and 2020. Multivariable Cox models were performed to assess duodenal stent failure, as defined by gastric outlet obstruction necessitating another duodenal stent. RESULTS: We included 129 patients 74 received a WallFlex® stent and 55 received an Evolution® stent. The non-failure rate was of 68% (95%CI 55-84) and 65% (95%CI 50-84) at 6 months and of 48% (95%CI 32-73) and 45% (95%CI 27-74) at 1 year, with the WallFlex® and Evolution® stents, respectively. The median time to duodenal stent failure was 10.5 months in the WallFlex® group and 9.3 months in the Evolution® group. The type of duodenal stent was not associated with duodenal stent failure (p logrank = 0.43, adjusted hazard ratio 1.55; 95%CI 0.77-3.14). The overall survival was similar between the two groups (p logrank = 0.92). Three patients had complications due to Evolution® stents; it consisted in dismantled stents that led to hemorrhage in one patient. CONCLUSIONS: WallFlex® and Evolution® duodenal stents had similar efficacy for malignant gastric outlet obstruction. There were more adverse events with Evolution® stents.