The effect of renal function change on renal cell carcinoma patients with tumor thrombus after nephrectomy and thrombectomy: a large Chinese center experience

BACKGROUND: To explore the influencing factors of perioperative renal function change and their relationship with prognosis on renal cell carcinoma (RCC) patients with tumor thrombus after nephrectomy and thrombectomy. METHODS: The clinical and pathological data of 135 patients with RCC and tumor thrombus, who underwent nephrectomy and thrombectomy at Peking University Third Hospital from May 2015 to July 2018, was retrospectively analyzed. Absolute change in estimated glomerular filtration rate (eGFR) (ACE) and percent change in eGFR (PCE) were calculated by preoperative and postoperative renal function. Linear regression analysis was used to explore the influencing factors of ACE and PCE, and logistic regression analysis was used to explore the influencing factors of worse postoperative renal function [eGFR≤60 mL/(min × 1.73 m^2)]. Cancer-specific survival (CSS) was estimated by Kaplan-Meier method and multivariate Cox regression, which were used to explore the effect of ACE and PCE on prognosis. RESULTS: Of all the 135 patients, 101 patients (74.8%) were male and 34 patients (25.2%) were female. The mean preoperative eGFR was 73.9 ± 21.8 mL/(min × 1.73 m^2) and postoperative eGFR was 69.5 ± 25.2 mL/(min × 1.73 m^2). In multivariate linear regression analysis, preoperative eGFR (P < 0.001) and pathological type (P = 0.038) were significant predictive factors of ACE. In aspect of PCE, preoperative eGFR (P < 0.001) and pathological type (P = 0.002) were significant predictors. In multivariate logistic regression analysis, preoperative eGFR (P = 0.016) was the only risk factor of predicting worse postoperative renal function. During follow-up, 22 patients (16.3%) were dead due to RCC. According to ROC analysis, the cut off value of ACE and PCE was 13.9 and 0.16, respectively. ACE> 13.9 and PCE > 0.16 indicated worse CSS (P = 0.006 and P = 0.047, respectively). However, in multivariate Cox regression analysis of several related factors, perinephric tissues invasion (P = 0.001), sarcomatoid differentiation (P = 0.001) and ACE> 13.9 (P = 0.002) were significant prognostic factors for CSS. PCE > 0.16 seemed to be not (P = 0.055). CONCLUSION: We explored several clinicopathological risk factors of predicting renal function change and their relationship with prognosis of RCC patients with tumor thrombus after nephrectomy and thrombectomy. The renal function change, which was associated with preoperative eGFR and pathological type, was prognostic risk factor for CSS and ACE> 13.9 indicated the worse prognosis.