Prostate capsule sparing versus nerve sparing radical cystectomy for bladder cancer: results of a randomized, controlled trial

Abstract

Purpose: Prostate capsule sparing and nerve sparing cystectomies are alternative procedures for bladder cancer that may decrease morbidity while achieving cancer control. However, to our knowledge the comparative effectiveness of these approaches has not been established. We evaluated functional and oncologic outcomes in patients undergoing these procedures.

Materials and methods: We performed a single institution trial in patients with bladder cancer in whom transurethral prostatic urethral biopsy and transrectal prostate biopsy were negative. Men were randomized to prostate capsule sparing or nerve sparing cystectomy with neobladder creation and stratified by Sexual Health Inventory for Men score (greater than 21 vs 21 or less). Our primary end point was 12-month overall urinary function as measured by Bladder Cancer Index. Secondary end points included sexual function, cancer control and complications.

Results: A total of 40 patients were enrolled in the study with 20 patients in each arm. Urinary function at 12 months decreased by 13 and 28 points in the prostate capsule and nerve sparing groups, respectively (p = 0.10). Sexual function followed a similar pattern (p = 0.06). There was no difference in recurrence-free, metastasis-free or overall survival (each p >0.05). The rate of incidentally detected prostate cancer was similar (p = 0.15).

Conclusions: Our study provides a randomized comparison of prostate capsule sparing and nerve sparing cystectomy techniques. We found no difference in functional or oncologic outcomes between the 2 approaches, although our study was underpowered due to a lack of patient accrual.

Keywords: cystectomy; mortality; prostate; urinary bladder neoplasms; urinary diversion.

Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1. Change in urinary function for patients randomized to prostate capsule sparing and nerve sparing cystectomy

Average urinary function at 12 months compared with baseline decreased by 13±30 points for prostate capsule sparing patients and decreased by 28±33 points for nerve sparing patients. There was no difference in urinary function between the two approaches (p=0.10). P value generated from Wilcoxon Rank test.

Figure 2. Change in sexual function stratified by SHIM score for patients randomized to prostate capsule sparing and nerve sparing cystectomy

In the nerve sparing cohort, 10 patients had a SHIM ≤21 and 10 patients had a SHIM >21. In the prostate capsule sparing cohort, 11 patients had a SHIM ≤21 and 9 patients had a SHIM >21. Average sexual function at 12 months compared with baseline decreased by 1±11 points for prostate capsule sparing patients and decreased by 23±30 points for nerve sparing patients. There was no difference in sexual function between the two approaches (p=0.06). P value generated from Wilcoxon Rank test.

Figure 3. Recurrence-free (A), metastatic-free (B), and survival (C) probability in patients randomized to prostate capsule sparing and nerve sparing cystectomy

Prostate capsule sparing and nerve sparing patients demonstrated no differences in recurrence-free, metastatic-free, or survival probability (all p>0.05). P value generated by the log-rank test.

Figure 3. Recurrence-free (A), metastatic-free (B), and survival (C) probability in patients randomized to prostate capsule sparing and nerve sparing cystectomy

Prostate capsule sparing and nerve sparing patients demonstrated no differences in recurrence-free, metastatic-free, or survival probability (all p>0.05). P value generated by the log-rank test.

Figure 3. Recurrence-free (A), metastatic-free (B), and survival (C) probability in patients randomized to prostate capsule sparing and nerve sparing cystectomy

Prostate capsule sparing and nerve sparing patients demonstrated no differences in recurrence-free, metastatic-free, or survival probability (all p>0.05). P value generated by the log-rank test.