CDKN2A and urinary bladder carcinoma: The results from 297 subjects with early-stage (Ta–T1) bladder cancer from four studies [5, 10, 12, 19] suggested that low expression of p16 was also significantly associated with poor PFS in early-stage bladder cancer (HR = 2.09, 95% CI = 1.21~3.63, and P = 0.002; I2 = 0%, P = 0.484).