Multicenter experience of the newly designed covered metallic ureteral stent for malignant ureteral occlusion: Comparison with double J stent insertion

Purpose: This study was designed to evaluate the effectiveness of the newly designed covered metallic stent (CMS) for malignant ureteral obstruction by comparing with double J stent (DJS). Material and Methods: CMSs were placed for malignant ureteral obstruction caused by various types of cancers for 42 ureters in 32 patients from 7 institutes. Retrospective data were collected for DJSs, which included 72 malignant ureteral occlusions in 56 patients from a single institute. Twenty-seven DJSs were placed percutaneously, and 45 DJSs were cystoscopically inserted. Technical failure of the CMS group was compared with that of the radiologically inserted DJS group. Primary patency of the CMS group was compared with assisted primary patency of the DJS group. Results: Technical failure of the CMS group is lower than that of the radiologically inserted DJS group: 0 % (0/42) vs. 25.9 % (7/27; p = 0.002), respectively. Primary patency of the CMS group is better than assisted primary patency of the DJS group (p = 0.012). Primary patency of the CMSs is 100, 94.5, 74.7, 70.3, 65.3, 65.3, and 65.3 % at 1, 3, 6, 9, 12, 18, and 24 months, respectively. Assisted primary patency of the DJS is 78.6, 75.1, 59.1, 48.7, 38.7, and 37.8 % at 1, 3, 6, 9, 12, and 18 months, respectively. No serious complications were noted in the CMS group. Migration of the metallic stent occurred in one patient (2.3 %). Conclusions: Covered metallic stent placement for malignant ureteral obstruction is superior to the double J stent placement in terms of technical success and patency.