Effect of a Risk-stratified Grade of Nerve-sparing Technique on Early Return of Continence After Robot-assisted Laparoscopic Radical Prostatectomy

Background: The impact of nerve sparing (NS) on urinary continence recovery after robot-assisted laparoscopic radical prostatectomy (RALP) has yet to be defined. Objective: To evaluate the effect of a risk-stratified grade of NS technique on early return of urinary continence. Design, setting, and participants: Data were collected from 1546 patients who underwent RALP by a single surgeon at a tertiary care center from December 2008 to October 2011. Patients were categorized preoperatively by a risk-stratified approach into risk grades 1-4, with risk grade 1 patients more likely to receive NS grade 1 or complete hammock preservation. This categorization was also conducted for risk grades 2-4, with grade 4 patients receiving a non-NS procedure. Intervention: Risk-stratified grading of NS RALP. Outcome measurements and statistical analysis: Univariate and multivariate analysis identified predictors of early return of urinary continence, defined as no pad use at <= 12 wk postoperatively. Results and limitations: Early return of continence was achieved by 791 of 1417 men (55.8%); of those, 199 of 277 (71.8%) were in NS grade 1, 440 of 805 (54.7%) were in NS grade 2, 132 of 289 (45.7%) were in NS grade 3, and 20 of 46 (43.5%) were in NS grade 4 (p < 0.001). On multivariate analysis, better NS grade was a significant independent predictor of early return of urinary continence when NS grade 1 was the reference variable compared with NS grade 2 (p < 0.001; odds ratio [OR]: 0.46), NS grade 3 (p < 0.001; OR: 0.35), and NS grade 4 (p = 0.001; OR: 0.29). Lower preoperative International Prostate Symptom Score (p = 0.001; OR: 0.97) and higher preoperative Sexual Health Inventory for Men score (p = 0.002; OR: 1.03) were indicative of early return of urinary continence. Positive surgical margin rates were 7.2% (20 of 277) of grade 1 cases, 7.6% (61 of 805) of grade 2 cases, 7.6% (22 of 289) of grade 3 cases, and 17.4% (8 of 46) of grade 4 cases (p = 0.111). Extraprostatic extension occurred in 6.1% (17 of 277) of NS grade 1 cases, 17.5% (141 of 805) of NS grade 2 cases, 42.5% (123 of 289) of NS grade 3 cases, and 63% (29 of 46) of NS grade 4 cases (p < 0.001). Some limitations of the study are that the study was not randomized, grading of NS was subjective, and possible selection bias existed. Conclusions: Our study reports a correlation between risk-stratified grade of NS technique and early return of urinary continence as patients with a lower grade (higher degree) of NS achieved an early return of urinary continence without compromising oncologic safety. (C) 2012 European Association of Urology. Published by Elsevier B. V. All rights reserved.