To determine the efficacy of our novel technique to prevent lymphocele formation after pelvic lymph node dissection (PLND) after robotic-assisted radical prostatectomy (RARP) using the existing peritoneum of the bladder.

We evaluated 155 consecutive patients undergoing RARP with PLND over 24 months. Group A included the first 77 patients with PLND using standard technique (no peritoneal flap). Group B included the subsequent 78 patients (1 patient excluded) with PLND and peritoneal interposition flap. The peritoneal interposition flap is created by rotating and advancing the peritoneum around the lateral surface of the ipsilateral bladder to the dependent portion of the pelvis and fixing it to the bladder itself. A cystogram was performed in 91% of the patients 7-14 days after the surgery. Lymphocele formation rates were compared (based on symptoms, cystogram findings, and radiographic confirmation).

The 2 groups were statistically equivalent in terms of prostate-specific antigen, age, blood loss, body mass index, Gleason score, prostate size, pathology, or heparin use. Lymphocele formation occurred in 9 of 77 (11.6%) group A patients and in 0 of 77 group B patients (P = .003). Mean time to lymphocele detection in group A was 30.4 days. Mean follow-up in groups A and B were 383.97 and 379 days, respectively (P = .91).

Strategic rotation and fixation of a peritoneal flap around the lateral aspect of the bladder during transperitoneal RARP with PLND is a novel technique to prevent lymphocele formation. Given the sample size and single institutional study, a prospective, randomized, multi-institutional trial is planned.