Renal functional outcomes after robotic multiplex partial nephrectomy: the National Cancer Institute experience with robotic partial nephrectomy for 3 or more tumors in a single kidney

To identify renal function outcomes after robotic multiplex partial nephrectomy (RMxPNx), we reviewed our institutional database at the National Institutes of Health, National Cancer Institute. To our knowledge, we present the largest series of RMxPNx renal function outcomes to date. Robotic partial nephrectomy has been employed for oncologic control and to prevent dialysis dependence in hereditary multifocal renal cell carcinoma conditions. We have termed robotic surgery on a single kidney with three or more lesions a RMxPNx. We evaluated patients from a prospectively maintained database at a single institution (NIH/NCI) that underwent RMxPNx from 2007 to 2013. Demographic and operative data were compiled with statistical analysis with T test performed to determine renal function outcomes. A total of 54 patients underwent RMxPNx. Mean number of tumors removed was 8.63 (range 3-52). Mean preoperative creatinine and eGFR were 1.02 +/- 0.26 mg/dL and 85.4 +/- 21.5 mL/min, respectively. Postoperatively, creatinine increased from baseline by 0.45 mg/dL (p < 0.001). Similarly, a mean decrease in eGFR by 24.6 mL/min was observed (p < 0.001). At 3-month follow-up, the creatinine increase from baseline was 0.05 mg/dL (p = 0.10) and mean decrease in eGFR was 3.01 mL/min (p = 0.21). When stratifying based on preoperative CKD stages I-III, similar results were observed. Robotic multiplex partial nephrectomy is a safe and feasible approach to patients with multifocal renal masses. These complex surgeries have a demonstrated learning curve, but this minimally invasive approach for nephron-sparing surgery allows patients to preserve renal function where they would otherwise require open surgery or a radical nephrectomy.