Quantitative assessment of fascia preservation improves the prediction of membranous urethral length and inner levator distance on continence outcome after robot-assisted radical prostatectomy

Aims: To determine whether preoperative prostate/pelvic anatomical structures and intraoperative fascia preservation (FP) predict continence recovery after robot-assisted radical prostatectomy (RARP).

Methods: Between January 2012 and March 2016, 439 prostate cancer (PCa) patients with normal preoperative continence were retrospectively included. FP score was defined as the extent of FP from base to apex of the prostate, quantitatively assessed by the surgeon. Anatomical prostate structures were measured on endorectal preoperative Magnetic Resonance Imaging. The International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) was used to assess urinary incontinence (UI). Cox analysis was used to determine predictive factors for early continence recovery. Finally a binary logistic regression analysis was performed to develop a risk calculator.

Results: At a median follow up of 12.1 months 50.8% of men reported UI. In the Cox multivariate analysis longer membranous urethral length (MUL; P < 0.0001; OR 1.309; CI 1.211, 1.415) and shorter inner levator distance (ILD; P < 0.0001; OR 0.904; CI 0.85, 0.961) were predictors of earlier continence recovery. In the multivariate binary logistic regression analysis longer MUL (P < 0.0001; OR 1.565, CI 1.362, 1.798), shorter ILD (P < 0.0001; OR 0.819, CI 0.742, 0.904) and higher FP score (P = 0.024; OR 1.089, CI 1.011, 1.172) were independent predictors of continence outcome. The risk calculator predicted continence recovery between 1.3% and 99%.

Conclusions: Preoperative longer MUL and shorter ILD, but also intraoperative FP independently improve continence recovery after RARP. The risk calculator could be used to identify patients at high risk of UI.