As shown in Table 2, in univariate analysis, T stage (p < 0.001), N stage (p < 0.001), M stage (p < 0.001), pathologic stage (p < 0.001), histologic grade (p < 0.001), and PIF1 expression (p < 0.001) were related to overall survival (OS); in multivariate analysis, only M stage (p < 0.002), histologic grade (p = 0.036), and PIF1 expression (p = 0.002) could act as independent prognostic factors for ccRCC (Table 2). This evidence concerns the gene PIF1 and nonpapillary renal cell carcinoma.