Robotic radical prostatectomy: difficult to start, fast to improve? Influence of surgical experience in robotic and open radical prostatectomy

Purpose The assistance of robotic systems raises the concern of whether there is an improved learning in robotic-assisted radical prostatectomy (RARP) compared to open retropubic radical prostatectomy (ORP). Methods We retrospectively analyzed data from 1438 patients who underwent ORP (n = 735) or RARP (n = 703). For each procedure, the level of experience of three different surgeons was summarized. Perioperative and pathological parameters reflecting surgical performance were compared between both learning curves. RARP data were influenced by new introduction of the robotic system. Results The median patient age at surgery was 66 years (IQR 42-80). Patients in the RARP group were younger (p < 0.001) and had a lower oncological risk (p < 0.001). Inexperienced RARP surgeons had a higher pT2-PSM rate and lower lymph node yield (13.8 +/- 4.7 vs. 14.7 +/- 4.8; p = 0.03) than inexperienced ORP surgeons. After 100 procedures, RARP and ORP surgeons had the same pT2-PSM rate (8% vs. 8%; p = 0.8) and lymph node yield (15.4 +/- 5.4 vs. 15.4 +/- 5.1; p = 1.0). In multivariate analysis for ORP, surgical inexperience (<= 100 cases) was an independent predictor of a longer operating time (OR 9.0; p < 0.001) and higher amount of blood loss (OR 2.9; p < 0.001). For RARP, surgical inexperience (<= 100 cases) was a predictor of a longer operating time (OR 3.9; p < 0.001), higher amount of blood loss (OR 1.9; p = 0.004), higher pT2-PSM rate (OR 1.6; p = 0.03), and lower lymph node yield (OR 0.6; p = 0.001). Conclusions Surgical experience has a relevant impact on perioperative and pathological parameters RARP has a higher initial pT2-PSM rate and lower lymph node yield than ORP. This is relevant for patient selection for novice teaching in RARP.