Analysis Of Clinical Outcomes After Different Surgeries For Localized Renal Tumors Assessed By R.E.N.A.L. Nephrometry Score System

Purpose:To describe and evaluate the relationships between the R.E.N.A.L. nephrometry score system (RNS) and surgical outcomes for patients with localized renal tumor undergoing different surgeries.Materials and methods:RNS and clinical outcomes of 152 patients with localized renal tumor who underwent surgeries by the same surgeon in our department during Sep.2008 and Dec.2014 had been retrospectively analyzed. Every renal mass was assigned an R.E.N.A.L. nephrometry score using computerized tomography imaging and then classified by RNS as low complexity, moderate complexity or high complexity category according to the total nephrometry score (TNS). Data was assessed by nonparametric test and receiver operating characteristic (ROC) curve analyses.Results:Of the 152 patients, there were 25(16.4%) low,65(42.8%) medium and 62(40.8%) high score lesions. The median TNS was 9 (range 4 to 12) and the median maximum diameter of renal tumor was 5.7cm (range 1.5 to 10.3) in all patients.54 of all underwent nephron-sparing surgery (NSS), in which 22 underwent open nephron-sparing surgery (ONSS) and 32 laparoscopic nephron-sparing surgery (LNSS). There were 98 patients who did radical nephrectomy (RN),55 with open surgical procedures and 43 with laparoscopic. The RNS was highly associated with the clinical symptoms, the estimated blood loss (EBL) and the decision-making for different operation methods (p< 0.001). With a lower TNS, the parameters decreased and LNSS were more likely to be chosen. TNS was significantly related to decision-making (p≤0.007). Optimal operating points demonstrated by ROC analyses were TNS> 9 (sensitivity 85.7%, specificity 85.1%) was able to predict the selection of RN and TNS≤8 (sensitivity 36.4%, specificity 100%) was able to predict the selection of LNSS.Conclusion:The RNS is a quantitative score system that can describe the anatomical features of renal tumor well. It could be used to stratify the complexity of tumor by TNS and may help surgeons to make surgical decisions: LNSS was commended when TNS≤8, while RN should be considered when TNS≥9. However, multicenter and different surgeons are required in a further research since this conclusion might only work for the particular surgeon in this research.