How to optimize the use of robotic assisted radical prostatectomy: The role of preoperative patient characteristics to identify ideal candidates for minimally invasive approach

INTRODUCTION & OBJECTIVES: Robotic-assisted radical prostatectomy (RARP) has gained increasing popularity in the urological community. However, this approach may be associated with increasing costs for national healthcare systems. We hypothesized that not all patients benefit at the same extent from minimally invasive surgery in terms of post-operative outcomes. Identification of these patients would be key to allocate resources where the maximum benefit can be expected. MATERIAL & METHODS: The study included 609 patients with PCa treated with RARP or ORP between February 2007 and July 2013 at a single referral tertiary centre by a single high volume surgeon. All patients had complete preoperative available data, including age at surgery, body mass index (BMI), Charlson comorbidity index (CCI), and preoperative erectile function (EF). The International Index of Erectile Function-Erectile Function Index (IIEF-EF) was used to evaluate EF after BNSRP. EF recovery was defined as an IIEF-EF domain score ≥22. Postoperative UC was defined as being completely pad-free over a 24-hour period. Patients were stratified according to their probability of postoperative erectile dysfunction: low (age≤65, IIEF-EF≥26, CCI≤1), intermediate (age 66-69 or IIEF-EF 11-25, CCI≤1), and high-risk (age≥70 or IIEF-EF≤10 or CCI≥2). Additionally we stratified patients according to their risk of urinary incontinence: very low (IIEFEF> 10, age10, age<65, and BMI≥25), intermediate (IIEF-EF>10 and age ≥ 65 years),and high-risk (IIEF-EF 1-10) based on previously published classification tools. The Kaplan-Meier method was used to test the impact of the surgical approach (RARP vs. ORP) on EF and UC recovery in the overall population, and after stratifying patients according to the risk group. RESULTS: At a mean follow up of 32.5 months (median 28), the 2-year EF and UC recovery rates were 52.9 and 76.0%, respectively. Overall, patients treated with RARP had higher EF (52.1 vs. 67.8%; p<0.001) and UC (72.0 vs. 87.4%; p<0.001) recovery rates. After stratifying patients according to EF risk groups, RARP led to higher EF recovery rates in individuals in the low- and intermediate-risk categories (all P<0.001). However this did not hold true in patients in the high-risk group, where the rates of EF recovery were not significantly affected by the surgical approach (31.5 vs. 39.3% for ORP and RARP, respectively; p=0.2). Similarly, when patients were stratified according to the risk of UC recovery, RARP was associated with a higher probability of postoperative continence recovery in patients included in the very low-, low-, and intermediate-risk groups (all p<0.001). However, when considering patients in the high-risk group, the rates of UC recovery were similar between the two surgical approaches (70.2 vs. 69.3% for ORP and RARP, respectively; p=0.3) CONCLUSIONS: RARP leads to higher UC and EF recovery rates compared to ORP. However, not all patients benefit from the minimally invasive approach at the same extent. In patients with the worse preoperative characteristics (i.e. older and sicker patients), RARP is not associated with better functional outcomes compared to ORP. Our findings indicate that, in order to allow a more rationale resource utilization, patient selection is crucial for the identification of the best candidate for RARP.