The infiltration levels of TIA-1+ and IFN-γ+ cells in NSCLC tissues decreased in the presence of lymph node metastasis and as the TNM pathologic stage increased (p<0.05, respectively), but the rate of TIA-1+ cell high infiltration in squamous cell carcinomas (57.4%) was obviously higher than that in adenocarcinomas (38.8%; p=0.04). This evidence concerns the gene IFNG and adenocarcinoma.