Outcomes and complications of pelvic lymph node dissection during robotic-assisted radical prostatectomy

Purpose: Describe the outcomes and complications of patients who underwent standard pelvic lymphadenectomy (SPLND) and extended PLND (EPLND), or who did not undergo PLND (non-PLND) at the time of robotic-assisted laparoscopic radical prostatectomy (RALP). Methods: Retrospective analysis of prospectively collected longitudinal data of 492 RALPs performed by a single surgeon (Kane) over a 5-year period. Patients are subdivided into three treatment groups: 54 EPLND; 231 SPLND; and 207 non-PLND. Indications for EPLND include Gleason score ≥8, PSA ≥10 ng/mL, and higher D'Amico risk group. Patient demographics, perioperative complications, and short-term oncologic outcomes are compared. Results: Patients who underwent EPLND had higher-risk prostate cancer as evidenced by higher mean PSA (8.5 ng/mL), biopsy Gleason sum (≥8) (57.7 %), and D'Amico risk group (75.9 %), compared to SPLND and/or non-PLND groups (p ≤ 0.001). The EPLND total lymph node yield was similar compared to SPLND (20 vs. 18; p = 0.070). When the EPLND (n = 41) and SPLND (n = 57) were examined among only high-risk patients, the lymph node (IQR) yields [20 (14-29) vs. 17 (12-23)] and the proportion of positive nodes [29.3 % (12/41) vs. 12.3 % (7/57)] differed significantly (p = 0.048 and p = 0.042, respectively). Complication rates for all groups were similar and lymphocele formation was 5 %; 2.5 % were clinically significant. Conclusions: Robotic PLND can be performed with nodal yield comparable to open or laparoscopic PLND. Robotic EPLND improves nodal yield and the proportion of high-risk patients with nodal metastases recognized. Robotic PLND is associated with an approximately 5 % lymphocele rate. There is no difference in complications between EPLND and SPLND.