Externally coated ureteral metallic stents: An unfavorable clinical experience

Objective: The purpose of the present study was to evaluate the use of externally coated stents in patients with malignant ureteral obstruction. Materials and Methods: We have prospectively evaluated 16 patients, 10 men and 6 women, with malignant ureteral obstruction treated successfully by placement of Passager metal stents (Boston Scientific, Natick, MA, USA) bypassing the stricture. Mean patient age was 65.6 years (range 62-78 years). Ureteral patency was confirmed 24 and 48 hours by injection of contrast material through the nephrostomy tube, and after patency confirmation the nephrostomy catheter was removed. Results: All stents were positioned successfully, and the postoperative course was uneventful. In 13 cases (81.2%) the prostheses finally migrated into the bladder hindering overall ureteral patency (mean time of migration: 1.5 months). Patency was achieved in the remaining ureters (n = 3), during the follow-up period (mean: 8 months, range 6-16 months), without any need for further intervention. Conclusion: The inappropriate anchorage and the increased ureteral peristalsis are the main causes of migration towards the bladder, thus, minimizing the usefulness of this stent for the treatment of ureteral strictures. (C) 2002 Elsevier Science B.V. All rights reserved.