The purpose of this study was to evaluate the known molecular markers,LunX, CK19, CEA, VEGF-C and hnRNP A2/B1, for their expression in lung cancer cells in peripheral blood and pleural fluid using real-time RT-PCR, with the ultimate goal of establishing a more reliable molecular diagnostic method as an adjunct to clinical decision-making. This evidence concerns the gene BPIFA1 and lung cancer.