Our results indicated a negative correlation between HLA DR expression on CD33dim HLA DR+ CD11b+ cells and lung cancer, i.e., the risk of lung cancer decreases with an increase in HLA DR expression on CD33dim HLA DR+ CD11b+ cells, an immunophenotype indicating the expression of both CD33 and CD11b on the cell surface of certain myeloid cells. This evidence concerns the gene CD33 and lung cancer.