Robot assisted extended pelvic lymphadenectomy at radical cystectomy: Lymph node yield compared with second look open dissection

Purpose Robot assisted radical cystectomy outcomes show feasibility and potential benefits for patient recovery. However, it is difficult to judge the completeness of extended robot assisted vs open pelvic lymph node dissection using only the lymph node count and template description. We performed a prospective protocol in which radical cystectomy and pelvic lymph node dissection done in robot assisted fashion were followed by second look open pelvic lymph node dissection. Our primary objective was to determine the fraction of lymph nodes yielded by robot assisted pelvic lymph node dissection. Materials and Methods Patients with pure transitional cell carcinoma and no locally advanced features were selected for robot assisted radical cystectomy. A team of 2 urological oncologists performed radical cystectomy and pelvic lymph node dissection in robot assisted fashion, followed by second look open pelvic lymph node dissection. Lymph nodes from robot assisted dissection were submitted in up to 8 separate specimens by anatomical location. Any additional specimens retrieved at open dissection were submitted separately. Results The protocol was completed in 11 patients from October 2007 to June 2009. The median yield of robot assisted and second look open pelvic lymph node dissection was 43 (range 19 to 63) and 4 (range 0 to 8), respectively, for an overall robot assisted yield of 93%. Of second look open pelvic lymph node dissections 67% were clear of residual tissue, 13% had tissue without lymph nodes and 20% had 1 or more lymph nodes. Median operative time for robot assisted pelvic lymph node dissection was 117 minutes. Concurrently open radical cystectomy without required multiple lymph node specimen submission yielded a median 24 nodes. Conclusions Our data showing a robot assisted pelvic lymph node dissection yield of 93% of that of open surgery should allay concern that the robot assisted technique limits the completeness of pelvic lymph node dissection.