Extraperitoneal versus transperitoneal approach for robot-assisted radical prostatectomy: a contemporary systematic review and meta-analysis

We aim to evaluate the differences in peri-operative characteristics, surgical complications, and oncological and functional control between the extraperitoneal RARP (EP-RARP) and transperitoneal RARP (TP-RARP). A comprehensive database search was performed up to March 2021 for eligible studies comparing outcomes between EP-RARP versus TP-RARP. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered with PROSPERO. A leave-one-out sensitivity analysis was performed to control for heterogeneity and risk of bias. A total of 16 studies were included with 3897 patients, including 2201 (56.5%) EP-RARPs and 1696 (43.5%) TP-RARPs. When compared to TP-RARP, EP-RARP offers faster operative time (MD - 14.4 min; 95% CI - 26.3, - 2.3), decreased length of post-operative stay (MD - 0.9 days, 95% CI - 1.3, - 0.4), and decreased rates of post-operative ileus (RR 0.2, 95% CI 0.1, 0.7) and inguinal hernia formation (RR 0.2, 95% CI 0.1, 0.5). There were no significant differences in total complications, estimated blood loss, positive surgical margins, or continence at 6 months. In this review, EP-RARP delivered similar oncological and functional outcomes, while also offering faster operative time, decreased length of post-operative stay, and decreased rates of post-operative ileus and inguinal hernia formation when compared to TP-RARP. These findings provide evidence-based data for surgical approach optimization and prompts future research to examine whether these findings hold true with recent advances in single-port RARP and outpatient RARP.