PGCKA1 and nonpapillary renal cell carcinoma: In order to further assess the prognostic value of C4ORF19 in ccRCC, K–M analyses were performed between patients with low and high expression of C4ORF19. A higher C4ORF19 expression level significantly correlated with a longer overall survival time, as illustrated in Figure 18B (p < 0.001).