Nomograms to predict 3-year biochemical recurrence after robotic-assisted laparoscopic radical prostatectomy based on preoperative and perioperative variables of 774 patients.

115 Background: Predictors of biochemical recurrence after robotic-assisted laparoscopic radical prostatectomy (RALP) are not well reported in the literature. We wanted to investigate preoperative predictors as well as the influence of nerve sparing and positive surgical margin status on 3-year biochemical recurrence. Methods: 774 patients with at least 3 year follow up had undergone RALP by a single surgeon at our institution. Biochemcial recurrence was defined as a postoperative PSA >0.2 ng/ml. Multivariable logistic regression models were used to develop the biochemical recurrence predictive nomograms: nomogram 1- age, BMI, PSA density, clinical stage, biopsy Gleason, percent positive cores, perineural invasion; nomogram 2- age, BMI, PSA density, clinical stage, biopsy Gleason, percent positive cores, perineural invasion, nerve sparing, positive surgical margins (none, unifocal, or multifocal). The predictive accuracy of the models was assessed in terms of discrimination and calibration. Results: Both ...