Extraperitoneal versus transperitoneal approach for robot-assisted radical prostatectomy: An updated systematic review and metaanalysis

Background: Extraperitoneal RARP (EP-RARP) has recently become a popular surgical approach and is often compared to the transperitoneal RARP (TP-RARP). We conducted a systematic review and meta-analysis of the available literature to evaluate the differences in peri-operative characteristics, oncological and functional control, and surgical complications between EP-RARP and TP-RARP. Methods: A comprehensive search of PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, Google Scholar, and select conference abstract publications was performed for eligible studies comparing outcomes between EP-RARP versus TP-RARP. This was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was prospectively registered with PROSPERO. A leave-one-out sensitivity analyses was performed to control for heterogeneity and risk of bias. Results: A total of 16 studies (three randomized controlled trials, five prospective, and eight retrospective studies) were included with a total pooled population of 3897 patients including 2201 (56.5%) EP-RARPs and 1696 (43.5%) TPRARPs. When compared to TP-RARP, EP-RARP offers faster operative time (MD: -14.4 minutes; 95% CI: -26.3, -2.3; p = 0.02), decreased length of post-operative stay (MD: -0.9 days, 95% CI: -1.3, -0.4, p < 0.0001), decreased rates of postoperative ileus (RR: 0.2, 95% CI: 0.1, 0.7, p = 0.009) and inguinal hernia formation (RR: 0.2, 95% CI: 0.1, 0.5, p = 0.001). There were no significant differences in total complications, estimated blood loss, positive surgical margins, or urinary continence at 6 months post- RARP. Conclusions: Based on the available evidence, 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 the TP-RARP. These findings provide evidencebased data for surgical approach optimization and prompts future research to examine whether these findings hold true with recent advances in singleport RARP and outpatient RARP.