Retrograde Ureteral Stents for Extrinsic Ureteral Obstruction: Nine Years’ Experience at University of Michigan

Abstract

To review our experience with retrograde ureteral stenting for extrinsic ureteral obstruction because previous reports have suggested only moderate success. We performed a retrospective review of the course of patients who underwent retrograde ureteral stent placement from March 1996 to April 2005. The gathered clinical parameters included stent failure, which was defined as any ureteral unit (UU) that remained obstructed. A total of 54 patients treated for extrinsic ureteral compression, representing 87 UUs, were followed for an average of 16 months (range 0.7 to 98) in successful cases. Of the stents, 68% were placed for malignancy, 23% for retroperitoneal fibrosis, and 9% for benign masses. The overall success rate was 84%, with malignancy, retroperitoneal fibrosis, and benign masses having an 81%, an 85%, and a 100% success rate, respectively. Fourteen UUs failed, with a mean time to stent failure of 4.8 months (range 0.07 to 27). Multiple stents were placed in 54 UUs, with a mean of 5.5 stent exchanges, at a mean interval of 3.6 months. On univariate analysis, only greater posttreatment creatinine was associated with stent failure (P <0.01), although stents placed for localized disease tended to be more successful than those placed for regional disease (100% versus 81%, P = 0.07). If initial stent placement was possible, extrinsic ureteral obstruction was managed successfully with retrograde ureteral stent placement in 84% of cases. Because no preoperative characteristics could be identified, except for a trend toward less success in cases of regional disease, retrograde stenting can be considered first-line treatment in patients with extrinsic ureteral obstruction.