CDKN2A and neoplasm: Generally, a strong and significant correlation between tumor tissue and autologous samples in P16INK4A promoter methylation was found across studies(Correlation coefficient 0.71, 95% CI: 0.51–0.83, P<0.0001), which suggested the higher frequency of methylation in autologous sample was found, the higher prevalence of methylation can be observed in cancer tissue in patients with NSCLC.