Expression of CA19-9, SLX, STN and CEA in relatively early gastric carcinoma

Expression and presence of the carbohydrate antigens CA19-9, SLX and STN, and CEA in tissues and serum were examined in 132 patients with early or propria muscle invaded gastric cancer. The seropositive rate was not different in patients with cancer or gastritis. In tumor tissue, the positive rate for these antigens was 28.8% in CA19-9, 9.1% in SLX, 47.0% in STN and 72.9% in CEA. Results showed that gastric cancers, even at an early stage, produce abnormal carbohydrate antigens not detected in normal tissues. However, transfer of antigens into the circulation was not observed in patients with early gastric cancer, suggesting the possibility that number of carcinoma cells may be involved in the transfer of antigens into blood.