Matched comparison of robot-assisted, laparoscopic and open radical prostatectomy regarding pathologic and oncologic outcomes in obese patients

To investigate pathological and oncological outcomes of obese patients who underwent robot-assisted radical prostatectomy (RARP) compared with laparoscopic radical prostatectomy (LRP) or open retropubic radical prostatectomy (RRP) since limited comparative data exist with regard to oncological and survival outcomes.A total of 869 patients with body mass index ≥ 30 from two academic centers were identified. A total of 194 patients who underwent RARP were propensity score (PS) matched 1:1 to LRP or RRP cases. PS-matching variables included prostate-specific antigen (PSA), biopsy Gleason score, clinical stage, surgeon experience, and nerve-sparing technique. Predictors of positive surgical margins (PSMs) were analyzed using logistic regression. Predictors of recurrence-free survival (RFS) were analyzed within Cox regression models. Overall survival was compared with RFS using the log-rank test.Pathologic Gleason scores7, =7, and7 were found in 24.2, 63.6, and 11.7 % of patients, respectively. There were no statistically significant differences related to pathologic stage or lymph node metastases between surgical techniques. PSM for pT2 disease were observed in 22.9, 17.4, and 19.3 % of patients undergoing RARP, LRP, and RRP, respectively (not significantly different). Preoperative PSA and clinical stage cT2 disease were independently associated with PSM. There were no significant differences in mean 3-year RFS for RARP, LRP, and RRP (87.4, 91.0, and 85.7 %). Biopsy Gleason score7, PSM, and clinical stage two were independent predictors of decreased RFS.RARP demonstrates similar pathological and oncological results compared with LRP or RRP for obese patients.