Demographic data
Of the 1004 patients, 452 (45.1%) underwent PN, and 552 (54.9%) underwent RN. The rate of PN for cT1 tumors increased from 5% in 2000 to 45% in 2018. The mean tumor sizes were 3.3 cm and 4.6 cm in the PN and RN groups, respectively, and the difference was significant (p =0.001) (see Table 1). The mean±SD preoperative eGFR was similar between the two groups: 100.7±26.4 and 96.9±34.6 ml/min/1.73 m2 in the PN and RN groups, respectively (p =0.72).