Robot-assisted pelvic lymphadenectomy for prostate cancer. Potentially advantageous in the elderly?

Background and Aims. Pelvic lymphadenectomy is the most effective method for the detection of lymph node metastases due to prostate cancer. Question remains whether robot-assisted pelvic lymphadenectomy provides the same number of nodes than open lymphadenectomy. We compared outcomes and number of nodes retrieved by the two procedures. Methods. Data of patients who had undergone pelvic lymphadenectomy during robot-assisted radical prostatectomy (Group A) between January 2016 and June 2018 were compared to those of a matched population having undergone pelvic lymphadenectomy during open retropubic prostatectomy (Group B). Results. The median number of removed lymph nodes was 11 (range 8-15) in Group A and 14 (range 12-16) in Group B (p = 0.05) but the rate of N+ patients was 11.4% in Group A and 14.7% in group B (p = 0.3). The median number of metastatic lymph nodes was 1 (range 1-1) in Group A and 2.2 (range 1-9) in Group B. There was no vascular complication but the rate of lymphocele requiring percutaneous drainage was 9% in Group B as opposed to none in Group A (p = 0.12) and mean age of patients suffering this complication was 70y. Conclusions. Robot-assisted pelvic lymphadenectomy provided a lower number of nodes than the open approach but this did not significantly change the number of patients diagnosed as N+. Though more time-con-suming, the robotic approach avoided pelvic lymphoceles which were seen in almost 10% of patients having undergone the open approach. The risk of such complication appeared to be related to age.