Robot-assisted laparoscopic prostatectomy: nodal dissection results during the first 440 cases by two surgeons

Although many studies address the learning curve for robot-assisted laparoscopic prostatectomy (RALP), little is known concerning the results for pelvic lymph node dissection (LND) during RALP.

Between 2006 and 2011, two surgeons performed 904 RALP procedures. LND was performed in 440 (48.6%) cases based on the European Association of Urology guidelines. Both surgeons had extensive experience with open LND for both prostate and bladder cancer. Clinical data were prospectively recorded into an online database. Complications were reported using the Clavien-Dindo system and documented prospectively.

For both surgeons, the operative time for LND decreased over time during the first 150 LND procedures. After that, a mean plateau of operative time of 49 minutes for LND was reached. Nodal yield increased from a mean of 10 nodes for the first 50 cases to 14 for cases 351 to 400. The percentage of positive nodes increased significantly in these intervals from 4% to 23.1% (P<0.001, Mann Whitney U test). Overall complications by grade were not significantly different between RALP with or without LND. In 440 LND cases, 5 (1.5%) grade IIIb complications occurred. All were infection related with bowel perforation in one. Symptomatic lymphoceles necessitating drainage were present in five (1.5%) men. Thromboembolic events (0% vs 1.5%) and anastomosis dehiscence (0.2% vs 1.1%) were more common in men with LND. During the learning curve, the incidence of Clavien grade I and II but not grade III and IV complications decreased.

An improvement pattern for LND during RALP is observed for operative time, nodal yield node positivity rate, and complication rate during the first 400 cases of LND.