Comparison of double-layered and covered Niti-S stents for palliation of malignant dysphagia

Background and Aim: Covered metal stents have been accepted as the treatment of choice for malignant dysphagia caused by esophageal and gastric cardia cancer, but stent migration is a major shortcoming. A double-layered Niti-S stent was therefore introduced to obviate this problem. We aimed to compare double-layered and covered Niti-S stents regarding safety, efficacy, and feasibility in the treatment of malignant dysphagia. Methods: Thirty-seven consecutive patients with malignant dysphagia due to inoperable esophageal or gastric cardia cancer were enrolled in a prospective, randomized study. The main outcomes were technical success, improvement in dysphagia score after stent insertion, and complications. Results: Technical success was achieved at a similar rate in both groups (covered, 19/19 [100%] vs double layered, 16/17 [94%]). A week after stent insertion, the mean dysphagia score improved significantly in the covered and double-layered groups compared to baseline (from 2.95 ± 0.52 and 2.88 ± 0.33 to 1.00 ± 0.47 and 1.06 ± 0.24, respectively; P < 0.001). There was no difference in the survival of the patients in the two groups. The overall complications, including stent migration and tumor overgrowth, occurred more frequently with covered stents (11/19 [58%]) than double-layered stents (2/17 [12%]; P = 0.006). Conclusion: Newly-developed, self-expanding metal stents, (covered and double-layered Niti-S stents) were equally effective and feasible treatments for malignant dysphagia. However, double-layered Niti-S stents are preferable due to their favorable safety profile.