To assess the association between the R.E.N.A.L. Nephrometry score, the amount of NNPV removed, and the renal function decline in patients undergoing robotic partial nephrectomy (RPN).
The Multi-Institutional Mount Sinai Kidney Cancer Database was used to identify 1235 patients who underwent RPN between January 2008 to February 2016¬ of which 366 had complete data including NNPV. Mann-Whitney U tests and univariable linear regression models were used to assess the relationships between R.E.N.A.L. Nephrometry score, warm ischemia time (WIT), and NNPV removed. Univariable and multivariable regression models were then used to assess the independent relationships of each of these variables with percent change in eGFR and acute kidney injury (AKI) within the first 30 post-operative days in addition to percent change in eGFR and progression to chronic kidney disease (CKD) at a median follow-up of 6.9 months.
Increasing R.E.N.A.L. Nephrometry score was shown to be a predictor of WIT (β= 0.92, p<.001) and of NNPV removed (β= 6.21, p<.001) in univariable analyses. In multivariable analysis, postoperative percent change in eGFR within the first 30 days was negatively associated with both R.E.N.A.L. Nephrometry score (β= -2.02, p<.001) and NNPV removed (β= -5.19, p=.015). R.E.N.A.L. Nephrometry score (OR= 1.21, p=.013) and NNPV removed (OR= 1.90, p=.013) were also associated with an increased likelihood of AKI. No significant association in this cohort was found between R.E.N.A.L. Nephrometry score, NNPV, or WIT and long term renal function decline.
The preoperative R.E.N.A.L. Nephrometry score can be used to predict postoperative pathologically-determined healthy renal volume loss, or NNPV. Removal of not just the tumor but the healthy surrounding parenchyma is important in determining renal function decline. As our understanding of the importance of renal volume loss grows, NNPV gains increasing utility as an easily determinable postoperative variable.
Journal of endourology / Endourological Society. 2016 Sep 07 [Epub ahead of print]
Fatima Z Husain, Daniel C Rosen, David Joseph Paulucci, John Sfakianos, Ronney Abaza, Ketan K Badani
Mount Sinai Health System, 5944, Urology, New York, New York, United States ; ., Icahn School of Medicine at Mount Sinai, 5925, Urology, New York, New York, United States ; ., Icahn School of Medicine at Mount Sinai Hospital, Urology , 5 E98th Street, 6th Floor , New York, New York, United States , 10029 ; ., Icahn School of Medicine at Mount Sinai, 5925, Urology, New York, New York, United States ; ., Ohio Health, Robotic Urologic Surgery, Dublin, Ohio, United States ; ., Icahn School of Medicine at Mount Sinai Hospital, Urology, New York, New York, United States ; .