Meta-analysis of transperitoneal versus extraperitoneal robot-assisted radical prostatectomy for prostate cancer

Objective: To conduct a meta-analysis of studies that compared transperitoneal (TP) and extraperitoneal (EP) robot-assisted radical prostatectomy (RARP). Materials and Methods: PubMed, the Cochrane Library, and EMBASE online databases were searched for studies released prior to June 2012. References were manually reviewed, and two researchers independently extracted the data. To assess the quality of the studies, the Scottish Intercollegiate Guidelines Network Methodology Checklist for case-control and cohort studies was applied. Results: One randomized controlled trial and five case-control studies were identified that met the inclusion criteria. Within these studies, 530 patients underwent EP-RARP, and 312 patients underwent TP-RARP. Operating room (OR) time for EP was shorter than for TP (mean difference,-25.551; 95% confidence interval [CI]-41.668 to-9.434; P=.002). For estimated blood loss, there was no significant difference between EP and TP (mean difference,-12.111; 95% CI-44.087 to 19.865; P=.458). There was a statistical difference in length of stay (LOS) between EP and TP patients (mean difference,-0.488; 95% CI-0.964 to-0.012; P=.044). There was no significant difference in margin positivity between EP and TP (odds ratio=1.023; 95% CI 0.656-1.573; P=.918). In complications including grade 2 or more than 2, there was also no difference between EP and TP (odds ratio=0.610; 95% CI 0.341-1.089; P=.094). Conclusions: This meta-analysis suggests that perioperative parameters, including OR time and LOS, may be more favorable for EP-RARP than for TP-RARP. However, the oncologic outcome of margin positivity did not demonstrate a significant difference between the EP and TP approaches.