In summary, we found that serum CEA and CYFRA21-1 and the location of original lung cancer (right mid lobe), maximum diameter, CT-detectable pleural fluid, pleural sign by CT, and PET/CT-predicted pleural invasion were good markers for the prediction of pleural invasion in non-small-cell lung cancer patients. The gene discussed is CEACAM5; the disease is non-small cell lung carcinoma.