Pelvic Anatomical Features After Retzius-Sparing Robot-Assisted Radical Prostatectomy Intended for Early Recovery of Urinary Symptoms.

Abstract

Purpose: To elucidate factors contributing to early urinary continence recovery after retzius-sparing robot-assisted radical prostatectomy (RS-RARP) by evaluating postoperative pelvic anatomical features between RS-RARP and conventional RARP (CON-RARP). Materials and Methods: We retrospectively examined 50 men who underwent RS-RARP (n = 25; the RS-RARP group) and CON-RARP (n = 25; the CON-RARP group) between October 2017 and June 2018. Perioperative outcomes and postoperative urinary continence were assessed in both groups. Anatomical features including the bladder neck-to-pubic symphysis ratio (determined from cystograms) and membranous urethral length (MUL) (determined from magnetic resonance imaging) were evaluated. Result: The daily urinary incontinence rate at discharge was significantly lower in the RS-RARP group than in the CON-RARP group (0.046 [range: 0.014-0.160] vs 0.357 [range: 0.139-0.616], p < 0.001). Postoperative urinary continence at 1, 3, 6, and 12 months was 80%, 92%, 96%, and 96% in the RS-RARP group and 24%, 40%, 68%, and 84% in the CON-RARP group, respectively (p < 0.001). The urgency scores in the international prostate symptom score (IPSS) questionnaire at 1 and 3 months were significantly lower in the RS-RARP than in the CON-RARP group (p = 0.028 and 0.033, respectively). The quality of life (QOL) indices were more significantly improved in the RS-RARP group than in the CON-RARP group 1 month (p = 0.027) and 3 months (p = 0.045) postoperatively. Receiver operating characteristic analysis revealed that a postoperative MUL of 12.1 mm (area under the curve: 0.852) was the optimal cutoff value predictive of continence recovery after 1 month. Multivariate analysis demonstrated that RS-RARP (odds ratio [OR]: 23.6; p < 0.001) and prostate volume (OR: 0.926; p = 0.049) were the independent factors of a longer MUL. Conclusions: RS-RARP results in an early continence recovery and a better urgency score in the IPSS by suppressing the descent of the bladder and maintaining a long MUL. RS-RARP may contribute to a better QOL recovery after RARP.