The aim of this study was to evaluate the effects of robot-assisted radical prostatectomy (RARP) on uroflowmetry (UF) parameters among men with baseline peak flow rates (PFR) <10 mL/s.
A single-surgeon RARP database of 1082 men who underwent prospective UF testing was analyzed. Men filled out International Prostate Symptom Score questionnaires and underwent uroflowmetry and post-void bladder ultrasound before surgery and at each follow-up visit. Patients were divided into 2 groups based on preoperative PFR: those with PFR <10 mL/s (n = 158) and those with PFR ≥10 mL/s (n = 924). Univariate and multivariate regression models tested the association of preoperative characteristics in predicting postoperative PFR improvement. Within the PFR <10 mL/s group, preoperative variables were analyzed to predict pathologic outcomes.
Three months after RARP, men with baseline PFR <10 mL/s had a 3-fold improvement in PFR (from mean of 7.0 to 24.2 mL/s), whereas in men with PFR ≥10 mL/s there was a 50% improvement (from mean of 19.7 to 28.9 mL/s; P < .001). Improvement in PFR remained stable for >5 years, but mean postoperative PFR was 20% lower in men with baseline PFR <10 mL/s. Preoperative prostate-specific antigen (odds ratio [OR] 0.75; 95% confidence interval [CI] 0.59-0.95) and PFR (OR 0.52; 95% CI 0.34-0.80) were independent predictors of the percentage improvement in men with baseline PFR <10 mL/s. Preoperative PFR ≤7 mL/s was an independent predictor of Gleason score ≥8 (P = .016), seminal vesicle invasion (P = .010), and lymph node invasion (0.029).
After RARP, PFR improved significantly, with the improvement persisting over long-term follow-up. However, men with baseline PFR <10 mL/s had a 20% lower postoperative PFR over 5 years, suggesting permanent damage to the bladder and the need for early treatment to maintain bladder health. There appears to be an association between baseline PFR ≤7 mL/s and adverse pathologic features.
Lower urinary tract symptoms. 2017 Nov 29 [Epub ahead of print]
Adam Gordon, Douglas Skarecky, Kara N Babaian, Harleen Dhaliwal, Thomas E Ahlering
Department of Urology, University of California Irvine, Orange, California.