Objective: We evaluated the association of body mass index (BMI) with perioperative outcomes in patientswho underwent laparoscopic or open radical nephroureterectomy. Materials and
Methods: This retrospectivesingle-center study included 113 patients who had been diagnosed with upper urinary tract cancer fromJanuary 1998 to June 2013 and were treated with laparoscopic nephroureterectomy (Lap group, n=60) or opennephroureterectomy (Open group, n=53). Laparoscopic nephroureterectomy was performed via a retroperitonealapproach following an open partial cystectomy. The two surgical groups were stratified into a normal-BMI group(<25) and a high-BMI group (BMI≥25). The high-BMI group included 27 patients: 13 in the Lap group and14 in the Open group.
Results: Estimated blood loss (EBL) in the Lap group was much lower than that in theOpen group irrespective of BMI (p<0.01). Operative time was significantly prolonged in normal-BMI patientsin the Lap group compared to those in the Open group (p=0.03), but there was no difference in operative timebetween the Open and Lap groups among the high-BMI patients. Multivariate logistic regression analysis of thedata for all the cohorts revealed that the open procedure was a significant risk factor for high EBL (p<0.0001,hazard ratio 8.02). Normal BMI was an independent predictor for low EBL (p=0.01, hazard ratio 0.25). Therewas no significant risk factor for operative time in multivariate analysis. There were no differences in bloodtransfusion rates or adverse event rates between the two surgical groups.
Conclusions: Laparoscopic radicalnephroureterectomy via a retroperitoneal approach can be safely performed with significantly reduced EBLeven in obese patients with upper urinary tract cancer.