CEACAM5 and lung cancer: This study analyzed HSP70-Ex in combination with currently used biomarkers, including carcinoembryonic antigen (CEA) and carcinoembryonic antigen 19-9 (CA19-9), by measuring HSP70-Ex levels in a group of patients with lung cancer and in a group of healthy patients; the results suggested that HSP70-Ex can be used for the initial diagnosis of early-stage lung cancer (155).