4913 A prospective, randomized study comparing three types of covered metal stents for the palliation of malignant dysphagia.

Abstract

A comparison of the merits of the three types of covered metal stents currently available, the Cook-Z® stent, the Ultraflex® stent and the Flamingo Wallstent®, had until now not been performed in a prospective, randomized study. Methods: 100 consecutive patients at 3 centers participated in the study. All patients had inoperable carcinoma of the middle (n=18) or distal (n=53) esophagus or cardia (n=29. The stents were placed by or under supervision of an endoscopist who was well acquainted with each of the different stent characteristics. Patients were randomized using a computer-generated allocation system. At entry, patients were stratified for location of the tumor in the esophagus or cardia and for prior radiation and/or chemotherapy. The three stented groups were compared for improvement of dysphagia score, complications, recurrent dysphagia and survival. Patients were followed for at least 4 months or until death. Results: At 4 weeks after stenting, mean dysphagia score (0 (normal) - 4 (total occlusion)) had improved significantly (Z-stent: 3.2. 0.7, Ultraflex stent: 3.3 ® 0.7 and Flamingo stent: 3.1. 0.9; p=0.08). There were no differences between the 3 stent types in the occurrence of major complications (Zstent: 11/33 (33%) (bleeding (7), perforation (2), fever (1) and severe pain (1)), Ultraflex stent: 8/34 (24%) (bleeding (5), perforation (2) and fever(1)) and Flamingo stent: 6/33 (18%) (bleeding (3), perforation (2) and pressure necrosis (1); p=0.23) or pain after placement (Z-stent: 6 (18%), Ultraflex stent: 3 (9%) and Flamingo stent: 9 (27%); p=0.14). Eight (24%) patients with a Z-stent, 9 (26%) patients with an Ultraflex stent and 11 (33%) patients with a Flamingo stent had recurrent dysphagia (p=0.73), which was mainly due to tumor overgrowth (Flamingo stent, Z-stent) or stent migration (Ultraflex stent, Z-stent). Median survival (in days) was similar for all 3 stent groups (Z-stent: 110, Ultraflex stent: 104 and Flamingo stent: 113; p=0.99). Conclusion: All currently available covered metal stents offer the same degree of palliation of malignant dysphagia at the same risk, but while stent migration can be avoided by the choice of stent, tumor overgrowth remains an intractable problem requiring a new approach.