Pre- and Postoperative Parameters on Magnetic Resonance Imaging Predict Continence Recovery after Laparoscopic Radical prostatectomy

Abstract

Background: To evaluate the association between pre- and postoperative parameters on magnetic resonance imaging (MRI) and continence recovery after laparoscopic radical prostatectomy (LRP). To develop a risk scoring system for predicting continence recovery after LRP. Methods: 73 patients who underwent LRP were retrospectively reviewed. Demographic characteristics, clinicopathologic outcomes and several MRI parameters before and after surgery were evaluated. Continence was defined as no pad per day. Early continence recovery was defined as continence recovery within 3 months. Kaplan-Meier analyses and log-rank test were used to compare time to continence recovery. Cox proportional-hazards regression analyses were performed to identify independent predictors of continence recovery. Results: Patients with smaller prostatic volume, shorter intravesical prostatic protrusion length (IPPL), shorter preoperative membranous urethral length (MUL), lower MUL-removal rate, triangular vesicourethral anastomosis (VUA) and neurovascular bundle sparing experienced a faster continence recovery (All, p < 0.05). Multivariate analyses revealed IPPL (hazard ratio [HR]: 0.94, p = 0.044), preoperative MUL (HR: 1.10, p = 0.032), MUL-removal rate (HR: 0.91, p = 0.007) and shape of VUA (square vs. triangle, HR: 2.30, p = 0.012) were independent predictors of continence recovery. The four parameters were therefore used to develop a risk scoring system, termed Post-Prostatectomy Incontinence Score (PPIS) and ranging from 0 to 4. We observed early continence recovery in 100%, 84.6%, 27.8%, 0% and 0% of patients with a PPIS of 0, 1, 2, 3, 4, respectively. Conclusion: IPPL, preoperative MUL, MUL-removal rate and shape of VUA were independently predictors of continence recovery. PPIS could accurately predict the early continence recovery after LRP.