Meta-analysis of the association between RASSF1 hypermethylation and smoking behavior among 1046 smoking NSCLC patients and 441 nonsmoking NSCLC patients indicated a statistical difference (the overall OR = 1.75, 95% CI = 1.15–2.65, p = 0.008). The gene discussed is RASSF1; the disease is non-small cell lung carcinoma.