title: Five-year experience with metallic stents for chronic ureteral obstruction.
abstract: OBJECTIVE
  We present 5 years of outcome data on metallic ureteral stents in a cohort of patients treated for chronic ureteral obstruction.
  
  
  METHODS
  We retrospectively identified and analyzed the records of all patients in whom a Resonance® Metallic Ureteral Stent was placed between early 2007 and late 2011 at our institution. We performed a descriptive analysis of key outcomes, including the failure and death rates, and stenting duration, defined as the time from initial stent placement to last stent failure or patient death. We also performed a secondary comparative analysis of patients with a benign vs malignant etiology of obstruction.
  
  
  RESULTS
  A total of 139 metallic stents were placed in 47 patients, including 27 (57%) with malignant and 20 (43%) with a benign etiology. Of the patients 15 (32%) had bilateral obstruction. Maximum followup was 59 months (mean 20, median 13, IQR 4-31). Stent failure occurred in 13 patients (28%), including 4 in the benign and 9 in the malignant group (p = 0.35). The median duration of stenting for benign and malignant obstruction was 22 (IQR 9-39) vs 7 months (IQR 3-25) (p = 0.106). Stenting duration was equivalent when controlling for the higher death rate in the malignant group.
  
  
  CONCLUSIONS
  Resonance metallic stents are an adequate management strategy for benign and malignant ureteral obstruction. A subset of patients in each group continued to do well at more than a 3-year overall duration of stenting. Failure rates were similar for benign and malignant etiologies.
authors.affiliation: Department of Urology, Loyola University Medical Center, Maywood, Illinois 60153, USA. akadlec@lumc.edu
authors.forename: Adam O
authors.initials: AO
authors.lastname: Kadlec
authors.forename: Chandy S
authors.initials: CS
authors.lastname: Ellimoottil
authors.forename: Kristin A
authors.initials: KA
authors.lastname: Greco
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Turk
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008670:Metals; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012189:Retrospective Studies; D018570:Risk Assessment; D017678:Sex Distribution; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D014517:Ureteral Obstruction / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy*; D014563:Urodynamics
chemical_list: D008670:Metals
keywords: LUTS; XRT; equipment failure; etiology; lower urinary tract symptoms; radiation therapy; stents; ureter; ureteral obstruction