Detection of gastric cancer by a combination of tissue polypeptide antigen (TPA), lipid-bound sialic acid (LBSA) and carcinoembryonic antigen (CEA)

In this study, the clinical significance of the tumor markers, tissue polypeptide antigen (TPA) and lipid-bound sialic acid (LBSA) in conjunction with carcinoembryonic antigen CEA, was tested in 52 gastric cancer patients. The incidence of elevated serum levels of these 3 markers was as follows: 63% (33/52) for TPA; 40% (21/52) for LBSA; 21% (11/52) for CEA. In a combination assay using all three tumor markers, 37 out of 52 gastric cancer patients (71%) showed a positive combination assay, while 5 out of 20 normal subjects (25%) showed a positive combination assay. In a discriminant analysis of the resulting data, 18 out of 52 gastric cancer patients (35%) were classified correctly based on an analysis of CEA alone. Furthermore, 25 out of 52 gastric cancer patients (48%) and all 20 normal subjects (100%) were classified correctly based on an analysis of all three variables. Our data suggest that TPA and LBSA are more sensitive than CEA as markers of gastric cancer, and that the simultaneous measurement of TPA and LBSA in conjunction with CEA is more useful in cancer detection than the measurement of CEA alone.