Objective: Palliation of malignant esophageal obstruction is an important clinical problem. Expandable metal stents are a major advance in therapy, but many stents become obstructed because of tumor ingrowth. The aim of this study was to compare a new, membrane-covered expandable metal stent to conventional prostheses in a randomized controlled trial.
Methods: Sixty-two patients with malignant inoperable esophageal obstruction at the gastroesophageal junction participated in the study. Patients were randomly assigned to covered or uncovered stents. The principal outcome measure was the need for reintervention because of recurrent dysphagia or migration. Secondary endpoints were relief of dysphagia measured by a dysphagia score (grade 0 = no dysphagia, grade 1 = able to eat solid food, grade 2 = semisolids only, grade 3 = liquids only, grade 4 = complete dysphagia) and the rate of complications and functional status. All patients were observed at monthly intervals until death or for 6 months.
Results: One week after stenting the dysphagia score improved significantly in both the uncovered (n = 32, 3 +/- 0.1 to 1 +/- 0.1 [means +/- SEMs], p < 0.001) and covered (n = 30, 3 +/- 0.1 to 1 +/- 0.2 [means +/- SEMs], p < 0.001) stents. Obstructing tumor ingrowth was significantly more likely in the uncovered stent group (9/30) than in the covered group (1/32) (p = 0.005). Significant stent migration occurred in 2/30 patients with uncovered stents, as compared with 4/32 patients in the covered group (p = 0.44). Reinterventions for tumor ingrowth were significantly greater in the uncovered stent group (27%), as compared with 0% in the covered group (p = 0.002). Life table analysis showed similar survival in both groups.
Conclusion: Membrane-covered stents have significantly better palliation than conventional bare metal stents because of decreased rates of tumor ingrowth that necessitate endoscopic reintervention for dysphagia.