Imaging

Abstract

Cases of stent failure that did not undergo PNT placement included 18 (13.0%) UU at a mean of 52.4 days (range 3 to 128). A total of 90 (89.1%) patients had metastatic cancer at stenting with 32.2% dead at 5.8 months (range 1 to 32). Univariate and multivariate analyses identified cancer diagnosis, baseline creatinine greater than 1.3 mg/dl and post-stent systemic treatment as predictors of stent failure. Proximal location of compression and treatment creatinine greater than 3.11 mg/dl were marginal predictors of failure on univariate analysis, while proximal location of obstruction was also marginally significant on multivariate analysis. No predictors were identified for early stent failure (less than 1 week).Conclusions: At almost 1 year followup stent failure due to extrinsic compression occurred in nearly half of treated patients. Analysis of data revealed a diagnosis of cancer, baseline mild renal insufficiency and metastatic disease requiring chemotherapy or radiation as predictors of stent failure. Managing extrinsic compression by retrograde stenting continues to be a practical but guarded decision and should be tailored to each patient. Editorial CommentThe article reviews a common clinical situation, that being placement of a ureteral stent for extrinsic ureteral obstruction. Almost half of the patients treated with ureteral stents failed within the first year, which is remarkably similar to prior reports. In the later years of this current series the success rate improved to greater than 60%. This might be due to different stent materials, but unfortunately the chart review was such that the authors could not reliably assess this factor. It makes sense that a stiffer and less compressible stent would fare better in this situation. Although one small series suggested that a stiffer stent maintained patency longer (1), this has yet to be confirmed in other series. An internal stent has attractiveness over a percutaneous nephrostomy tube for long-term management, but this approximately 50% failure rate must be acknowledged when counseling patients and when performing follow-up. IMAGING _______________________________________________________________________Baseline staging of newly diagnosed prostate cancer: a summary of the literature Abuzallouf S, Dayes I, CT urography protocol is possible. Since CT urography is still an evolving technique we believe that further improvement of an optimized protocol will be developed very soon.