Our results of NSCLC indicated that MGMT hypermethylation varied with ethnicity (Caucasian: OR = 4.56, 95% CI = 2.63~7.92, p < 0.00001; Asian: OR = 5.18, 95% CI = 2.03~13.22, p = 0.0006), control style (Auologous: OR = 4.44, 95% CI = 3.32~5.92, p < 0.00001; Heterogeneous: OR = 9.05, 95% CI = 1.79~45.71, p = 0.008) and detection method (MSP: OR = 6.78, 95% CI = 3.40~13.51, p < 0.00001; RT-MSP: OR = 2.91, 95% CI = 1.87~4.53, p < 0.00001). This evidence concerns the gene MGMT and non-small cell lung carcinoma.