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