The renal functions of 215 patients (24 with benign renal mass, the rest with RCC staged T1-T2) who underwent partial nephrectomy (PN) between 2003 and 2014 were evaluated to identify predictors of short- and long-term deterioration in renal function after PN among renal cell carcinoma (RCC) patients with or without preoperative predisposition to chronic kidney disease (CKD) and among patients with benign renal mass. The 1- and 5-year predictive factors for de novo CKD were statistically analyzed. The incidence of de novo CKD differed significantly (p