Retzius-sparing robot-assisted radical prostatectomy improves early recovery of urinary continence: a randomized, controlled, single-blind trial with a 1-year follow-up

Objective: To evaluate the impact of Retzius-sparing robot-assisted radical prostatectomy (posterior approach) on early recovery of urinary continence (UC) compared to the conventional approach (anterior approach) for the treatment of clinically localized prostate cancer (PCa). Methods: A total of 110 consecutive patients with clinically localized PCa were prospectively randomized in a 1:1 ratio to an anterior group (n = 55) or a posterior group (n = 55). The primary outcome was immediate UC, defined as freedom from any pad use within 1 week after removal of the urinary catheter. The UC rate following surgery was also calculated with Kaplan–Meier curves, and the log-rank test was used for statistical comparison. Intra-operative outcomes, pathological data and oncological outcomes, including positive surgical margin (PSM) status and biochemical recurrence-free survival (BCRFS), were also compared between the two groups. The comparison of the two approaches was also analysed in subgroups after risk stratification. Results: Of the patients who underwent the posterior approach, 69.1% achieved immediate UC compared with 30.9% in the anterior group (relative risk 2.24, 95% confidence interval [CI] 1.48–3.51; P = 0.000). The relative Kaplan–Meier curves for UC during the 12-month follow-up revealed statistically better recovery in the posterior group when compared with the anterior group (hazard ratio [HR] 1.51, 95% CI 1.01–2.24; log-rank P = 0.007). No statistically significant differences were observed between the groups regarding complications (P = 0.399), PSM status (P = 0.225) or BCRFS (HR 4.80, 95% CI 0.97–23.78; log-rank P = 0.111). In sub-analyses, no significant difference between the two approaches with regard to UC recovery in patients with high-risk PCa was observed (HR 1.26, 95% CI 0.63–2.51; log-rank P = 0.415). Conclusions: The Retzius-sparing approach significantly improved early recovery of UC compared to the conventional approach. Further prospective studies are needed to confirm the benefits of the Retzius-sparing approach for clinically localized PCa, especially for high-risk cases.