Among the 37 articles, 26 studies [4, 5, 8–21, 28–34, 39, 41, 42] investigated the relationship between low expression of p16 and prognostic parameters in bladder cancer patients (RFS, OS, PFS, and DSS/CSS), and 30 studies [4, 10–13, 15–19, 21–40] assessed the association between p16 and clinicopathological factors in patients with bladder cancer. This evidence concerns the gene CDKN2A and urinary bladder cancer.