The robotic era of radical prostatectomy: A retrospective analysis of patient characteristics in contemporary robotic and open prostatectomy

Abstract

e16061 Background: As new treatment options become available without being tested in randomized controlled trials, trends in the patient populations receiving these novel therapies often emerge prior to the determination of ideal patient selection factors. In the case of robotic-assisted laparoscopic radical prostatectomy (RALRP), biases in patient selection for this relatively new procedure may influence the evaluation of postoperative outcomes in comparison to open retropubic radical prostatectomy (RRP). This study describes the disease-specific characteristics of patients currently undergoing RALRP and RRP in a contemporary fashion at a single institution. Methods: A total of 1,088 patients who had surgery since the inception of RALRP at our institution (2003–2007) were identified for analysis. The cohort was divided into two groups based on surgical technique (RALRP versus open RRP). Characteristics of the patient pool analyzed included age at surgery, Kattan Nomogram (KN) score, preoperative prostate-specific antigen (PSA), Gleason sum (GS) at biopsy, and pathological tumor stage. Unpaired t-tests with Welch correction and Mann-Whitney tests were used to determine the differences in patient characteristics between the two surgical approaches. Results: The median age was 61. The mean preoperative PSA was 6.2, and GS 2–6, 7, and 8–10 of 48.2%, 40.4%, and 11.4%, respectively. 519 and 569 patients underwent RALRP and RRP, respectively. There was a significant difference between GS (p<0.0001) and tumor stage (p=0.002) between patients undergoing the two approaches. There were trends in favor of younger age, decreased preoperative PSA, and better KN scores in the RALRP group, but these observations lacked statistical significance (age: p=0.06, PSA: p= 0.07, KN: p=0.15). Conclusions: Although there is insufficient evidence to declare an overall difference in patient characteristics between these two surgical approaches in our patient population, trends toward lower-risk patients in the RALRP group suggest a series of patient selection forces for this procedure. These observations have the potential to influence the results obtained in retrospective analyses comparing outcomes between RALRP and open RRP. No significant financial relationships to disclose.