Clinical Outcomes of Pelvic Lymph Node Dissection Before Versus after Robot-Assisted Laparoscopic Radical Cystectomy

Objective: The purpose of this study was to compare the clinical outcomes of bladder cancer patients treated with extended pelvic lymph node dissection (ePLND) before or after cystectomy under robotic-assisted radical cystectomy (RARC).Methods: A retrospective study to identify 348 patients with bladder cancer who underwent RARC was performed. Of the patients, 152 (42.8%) underwent ePLND before radical cystectomy (RC) (group A) and 196 (56.3%) underwent ePLND after RC (group B). The clinical, pathological, and overall survival were compared.Results: The total and RC operation time in Group A (total: 130.68 +/- 29.25 minutes, RC: 59.45 +/- 28.63 minutes) were both shorter than Group B (total: 154.17 +/- 38.18 minutes, RC: 94.81 +/- 41.21 minutes) (P < .05). However, no significant difference in time of ePLND. The estimate blood loss (EBL) of RC part and total operation (RC+ePLND) in group A was less than group B (both P < .05), while the ePLND part did not show significance. The result of vascular and nerve injury and surgical drain withdrawal time were similar in two groups. The total number of lymph nodes in group A was fewer than group B (16 versus 26; P < .05). Moreover, the number of bilateral internal iliac and presacral lymph nodes of group A was fewer than group B significantly, whereas the number of bilateral external iliac, common iliac, and obturator lymph nodes was similar in two groups. The lymph node density of group A was significantly lower than group B. The median follow-up of all patients was 33.0 months. Importantly, the survival of group B was better than group A (hazard ratio: 1.412; 95% confidence interval: 1.004-1.987; P = .048).Conclusions: Performing ePLND before RC reveals better result on operation time and EBL, while, when ePLND after RC, the total number of lymph nodes dissected is more and the survival is better. It recommended ePLND be performed before RC, and it is necessary to recheck the internal iliac and presacral area after cystectomy.