Lower expression levels of Exo-GAS5 in NSCLC patients than healthy donors. Higher Exo-GAS5 in early stages. Exo-GAS5 is a better prognostic marker than carcinoembryonic antigen (CEA). Lower expression of Exo-GAS5 correlates with larger tumors. n = 104. The gene discussed is CEACAM5; the disease is non-small cell lung carcinoma.