The effectiveness of resonance metallic stents for alleviating malignant ureteral obstruction:outcomes and initial experiences / 中华泌尿外科杂志

ABSTRACT

Objective To present the primary effectiveness and morbidity of metallic ureteral stent in treating the patients with malignant ureteral obstruction .Methods The retrospective study enrolled 11 patients received metallic ureteral stent placement because of malignant ureteral obstruction at our hospital between Jul.2012 and Jan.2014.Total of 16 stents were inserted including 5 bilateral stent insertion. There were 4 males and 7 females, with a mean age of 56 years (range 28 to 88 years).Mild to moderate hydronephrosis were identified by ultrasound and CTU in all patients , including 2 recurrent fever and 1 renal colic in affected side , however serum creatinine level is normal .There were 10 patients received stents insertion through cystoscopic or nephroscopic retrograde approach and 1 through nephroscopic antegrade approach,under superficial , spinal or intravenous anesthesia .Patients were scheduled for follow-up at 6 months intervals by KUB and ultrasound and would be examined ahead of time if there were any obstructive symptoms including recurrent fever or renal colic of the affected side .Outcomes and complications were observed during follow-up.Results In total,11 patients underwent 13 operations,including 2 by staging operations.Hydronephrosis , recurrent fever and renal colic were relieved in all patients after operation , showing 100%success rate.The mean follow-up was 9 months,in which,9 patients had not reached the scheduled time (1 year) while 2 patients exceed the time limit of stent exchange because of poor physical status.During the follow-up, 1 patient died of the progression of urothelial carcinoma .Nine stents of 5 patients keep alleviating the obstruction without hydronephrosis evaluated by ultrasonography .Stents failure occurred in 6 ureters of 5 patients, including 3 encrustation and 2 migration, presenting of progressive hydronephrosis and recurrent fever . Functional restoration was achieved in one of the encrusted stent undergoing ESWL .One stent with encrustation fail to be removed and a polymer double-J stent replacement in the same side was required for drainage .The other 3 nonfunctional stents were removed and replaced by polymer double-J stents.Conclusions Ureteral obstruction secondary to extrinsic compression contributing to relatively stable malignant tumor could be treated safely and sufficiently with the resonance metallic stent . Surveillance on schedule and regularly change within 1 year is critical to achieve successful outcomes .Tumor progression with ureteral invasion as while as encrustation can cause stent failure ,and in these cases the stent should be changed every 6 months or less.