Development of the clinical calculator for mortality of patients with metastatic clear cell type renal cell carcinoma: An analysis of patients from Korean Renal Cancer Study Group database

PURPOSE: To develop the clinical calculator for mortality of patients with metastatic renal cell carcinoma (mRCC) using Korean Renal Cancer Study Group (KRoCS) database. MATERIALS AND METHODS: Data from 1,115 patients with mRCC treated in 4 hospitals joining KRoCS between 1993 and 2016 were pooled. Five-year survival rates were calculated using Kaplan–Meier curve. A clinical calculator for 5-year mortality was developed using multivariable logistic regression analysis and validated externally using dataset including 916 patients from 4 other hospitals. RESULTS: Overall survival rates and cancer specific survival rate at 5 years were 28.5% and 29.4%, respectively. Among baseline factors, increased neutrophil-lymphocyte ratio (≥4), synchronous metastasis, low albumin (<3.0 g/dL), and low hemoglobin (<lower limit of normal: male, 13 g/dL; female, 11.5 g/dL) were the significant factors in 5-year mortality. Good internal validity was demonstrated with area under the curve estimates being 0.774 at 5-year mortality calculation and the calibration plot. In the external validation, 758 (82.8%) died by 5 years among these patients, with the average model-predicted rate of 72.9%. CONCLUSIONS: A clinical calculator has been developed to quantify the risk of death for individual patients after treatment of mRCC. This tool may be useful for patients or their guardians who want to know their prognosis and to identify patients requiring aggressive therapy and additional supportive measures during and after treatment.