CEACAM5 and neoplasm: The regular reference tumor-associated antigens carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were within the normal value range (termed non-cancer) with the AUC of 0.669 and 0.622, respectively, indicating the great potential of exosomal proteins as cancer biomarkers with higher specificity and sensitivity than a regular signature.