Multicenter experience with metallic ureteral stents for malignant and chronic benign ureteral obstruction.

BACKGROUND AND PURPOSE: A new coil-based metallic ureteral stent offers greater radial strength with longer indwelling time compared with plastic stents. This multicenter retrospective study reviews the clinical experience with this stent for malignant or benign chronic ureteral obstruction. PATIENTS AND METHODS: Patients had stent placement in a retrograde fashion. We analyzed preplacement and postplacement renal imaging to determine degree of hydronephrosis. Stent encrustation was determined by either visual inspection at the time of stent change or plain abdominal radiography. Preoperative and follow-up serum creatinine values were compared for each patient. RESULTS: A total of 76 stents in 59 renal units (40 patients) were successfully placed. Creatinine value follow-up on 54 renal units showed 20 (37%) units to have stable, 15 (28%) improved, and 19 (35%) with worsening values. No stent showed encrustation on plain radiography despite it being seen on two during direct visualization. Three stents needed operative removal with either percutaneous nephrolithotomy or cystolitholapaxy. Fifteen of 41 (37%) metallic stents placed because of an obstructed plastic stent also became obstructed. At last follow-up, 6 of 40 patients were kept from nephrostomy tubes because of the metallic stent. CONCLUSIONS: Metallic stents are a viable alternative to nephrostomy tubes in patients in whom conventional stents fail because of malignant obstruction, but patients need to be followed closely. Stent encrustation that resulted in retained stents was poorly visualized on plain radiography. Patients still remain at risk for obstruction, urinary tract infections, and lower urinary tract symptoms from the metallic stent.

Histopathologic outcomes of robotic radical prostatectomy.

Robotically assisted laparoscopic radical prostatectomy is a minimally invasive alternative for the treatment of prostate cancer. We report the histopathologic and short-term PSA outcomes of 500 robotic radical prostatectomies. Five hundred patients underwent robotic radical prostatectomy. The procedure was performed via a six trocar transperitoneal technique. Prostatectomy specimens were analyzed for TNM stage, Gleason's grade, tumor location, volume, specimen weight, seminal vesicle involvement, and margin status. A positive margin was reported if cancer cells were found at the inked specimen margin. PSA data were collected every 3 months for the first year, then every 6 months for a year, then yearly. The average preoperative PSA was 6.9 (1-90) with Gleason's score of 5 (2%), 6 (52%), 7 (40%), 8 (4%), and 9 (2%); postoperatively, histopathologic analysis showed Gleason's 6 (44%), 7 (42%), 8 (10%), and 9 (4%); 10, 5, 63, 15, 5, and 2% had pathologic stage T2a, T2b, T2c, T3a, T3b, and T4, respectively. Positive margin rate was 9.4% for the entire series. The positive margin rate per 100 cases was: 13% (1-100), 8% (101-200), 13% (201-300), 5% (301-400), and 8% (401-500). By stage, it was 2, 4, and 2.5% for T2a, T2b, T2c tumors; 23% (T3a), 46% (T3b), and 53% (T4a). For organ-confined disease (T2), the margin rate was 2.5% and it was 31% for nonorgan-confined disease. There were a total of 47 positive margins, 26 (56%) posterolateral, 4 (8.5%) apical, 4 (8.5%) bladder neck, 2 (4%) seminal vesicle, and 11 (23%) multifocal. Ninety-five percent of patients (n = 500) have undetectable PSA (<0.1) at average follow-up of 9.7 months. Recurrence has only been seen with nonorgan-confined tumors. Of those patients with a minimum follow-up of 1 year (average 15.7 months), 95% have undetectable PSA (<0.1). Our initial experience with robotic radical prostatectomy is promising. Histopathologic outcomes are acceptable with a low overall, positive margin rate. Short-term biochemical recurrence-free survival has also been good. We believe that the precise dissection allowed by the advantages of laparoscopic robotic surgery will translate into excellent long-term oncologic outcomes. At this time, the lack of maturity of the PSA data prevent definitive comparison to the open approach.