COL6A2 and nonpapillary renal cell carcinoma: Multivariate analysis confirmed that high COL6A2 expression (HR = 1.354, 95% CI: 1.108-1.656), older age (HR = 1.810, 95% CI: 1.173-2.793), distant metastasis (HR = 2.410, 95% CI: 1.412-4.111), and higher histological grade (HR = 1.663, 95% CI: 1.014-2.729) remained independent predictors of poorer OS in ccRCC (Table 2).