Robotic-assisted prostatectomy and open radical retropubic prostatectomy for locally-advanced prostate cancer: multi-institution comparison of oncologic outcomes

Purpose: Robotic-assisted laparoscopic prostatectomy (RALP) offers reportedly comparable oncologic outcomes for localized disease compared with open radical retropubic prostatectomy (ORRP). However, the oncologic efficacy of RALP in locally-advanced prostate cancer (PCa) is less clear. We report and compare our experience with RALP and ORRP in men with locally advanced PCa. Methods: Patients with locally advanced PCa (stage T3 or greater) were identified in both robotic and open cohorts. Clinicopathologic features including age, clinical stage, prostate-specific antigen, surgical margins, and Gleason score were reviewed. We further examined the incidence of positive surgical margins, the effect of the surgical learning curve on margins, and the need for adjuvant therapy. Results: From 1997 to 2010, 1,011 patients underwent RALP and 415 patients were identified who underwent radical retropubic prostatectomy (RRP) across four institutions. 140 patients in the RALP group and 95 in the RRP group had locally advanced PCa on final pathology. The overall robotic positive margin rate 47.1% compared with 51.4% in the RRP group. A trend towards a lower positive margin rate was seen after 300 cases in the RALP group, with 66.7% positive margin rate in the first 300 cases compared with 41.8% in the latter 700 cases. In addition, a lower incidence of biochemical recurrence was also noted in the latter cases (30.6% vs. 9.5%). Conclusions: Up to 2 out of 3 men undergoing RALP for locally-advanced PCa had positive margins during our initial experience. However, with increasing surgeon experience the overall positive margin rate decreased significantly and was comparable to the positive margin rate for patients with locally advanced disease undergoing ORRP over four academic institutions. We also noted a lower incidence of biochemical recurrence with increasing RALP experience, suggesting better oncologic outcomes with higher volume. Given this data, RALP has comparable oncologic outcomes compared to ORRP, especially with higher volume surgeons.