Comparison of Open and Robot-Assisted Pelvic Lymphadenectomy for Prostate Cancer

Purpose: We evaluated whether there were differences in the lymph node yield and incidence of nodal metastasis among patients undergoing robot-assisted radical prostatectomy with pelvic lymphadenectomy ( LAD) and open radical retropubic prostatectomy with either a standard or extended node dissection. Patients and Methods: Data were collected retrospectively on all patients undergoing radical prostatectomy with pelvic LAD at our institution between January 2006 and December 2008. Patients in group 1 ( n = 60) underwent robot-assisted standard LAD, those in group 2 ( n = 64) had open standard LAD, and group 3 patients ( n = 43) were treated with open extended LAD. Statistical comparison was then made between the three groups stratified by histologic grade and pathologic stage. Results: The mean lymph node yield was 8.2 for group 1, 7.6 for group 2, and 14.8 for group 3. The overall incidence of positive nodes in each group was 3.3%, 1.6%, and 18.6%, respectively. There were no differences between the node counts ( P = 0.84) and probability of finding positive nodes between the robot-assisted and open standard dissections. The extended LAD identified patients with positive nodes at a greater frequency, although those patients were more likely to have adverse pathologic features. Complications related to the lymphadenectomy were not different between the groups. Conclusion: The lymph node yield obtained during robot-assisted pelvic lymphadenectomy for prostate cancer is comparable to an open approach using a similar template. An open extended node dissection yields more nodes and identifies a greater number of patients with lymph node involvement.