Standard vs delayed ligature of the dorsal vascular complex during robot-assisted radical prostatectomy: results from a randomized controlled trial

Purpose: Prospective randomized trial to compare standard vs delayed approach to dorsal vascular complex (s-DVC vs d-DVC) in robot-assisted radical prostatectomy (RARP). Methods: Patients scheduled for RARP were randomized into a 1:1 ratio to receive either s-DVC or d-DVC by two experienced surgeons. In s-DVC arm an eight-shaped single stitch was given at the beginning of the procedure and the DVC was subsequently cut at time of apical dissection; in d-DVC arm the plexus was transected at the end of prostatectomy, prior to apex dissection and then sutured. Primary endpoint was difference in estimated blood loss (EBL) and a sample size of 226 cases was calculated; ad interim analysis was planned after 2/3 of recruitment. Results: Endpoint was reached at ad interim analysis after 162 cases (81 s-DVC, 81 d-DVC) and recruitment was, therefore, interrupted. Baseline and tumor characteristics were overlapping. EBL was significantly higher in d-DVC arm (mean EBL 107 vs 65 ml, p = 0.003), but without differences in post-operative hemoglobin, transfusions and complications. Overall PSM rate was higher in d-DVC arm (21.0 vs 14.8%, p = 0.323), with statistical significance relatively to organ-confined disease (15.5 vs 3.6%, p = 0.031). Apical involvement was instead significantly higher in s-DVC arm (prevalence in PSM patients 66.7 vs 23.5%, p = 0.020). Post-operative PSA, continence and potency rates were similar between groups. Conclusions: Standard and delayed approaches to DVC are safe and lead to similar functional outcomes. A delayed approach exposes to a higher risk of PSM in organ-confined disease but with a lower risk of apical involvement.