Learning Curve of Single-Port Robotic-Assisted Extraperitoneal Radical Prostatectomy: A CUSUM-Based Analysis.

Single-port robotic-assisted radical prostatectomy (SP-RARP) has been demonstrated to be a feasible and safe procedure. Nonetheless, the challenges of SP surgery could limit the transferability of skills from multi-port (MP) console. The aim of our study was to assess the learning curve of SP-RARP. SP-RARPs performed by a single experienced surgeon were reviewed. The surgical learning curve was assessed using risk-adjusted cumulative summation (CUSUM) methodology in terms of operative time, separately for SP-RARPs with pelvic lymphadenectomy (PLND) and without PLND. 119 extraperitoneal SP-RARPs were evaluated, 83 with PLND and 36 without PLND. After CUSUM calculation, a cubic polynomial regression was performed to plot the learning curves. The inflection points, representing the number of cases required to achieve proficiency, corresponded to the 42 and 20 procedure, respectively, for SP-RARP with and without PLND. The learning curves were subsequently divided into a learning phase and a proficiency phase to compare perioperative and postoperative outcomes of the two phases. In both groups, cases in the proficiency phase demonstrated significantly lower median operative times ( = .01 and < .001) and hospital stays ( = .015 and = .04). In the SP-RARP without the PLND group, patients in the proficiency phase demonstrated significantly lower postoperative pain scores ( = .04). No differences were found in terms of estimated blood loss, complication rates, and positive surgical margin rates ( > .05). Results from our analysis suggest that the learning curve of extraperitoneal SP-RARP is not longer than that reported for MP-RARP. Moreover, when cautiously approached, the learning process can be undertaken without compromising safety and oncological outcomes.