[Initial basic and clinical evaluation of a solid-phase immunoradiometric assay for sialyl SSEA-1 antigen: 2. Evaluation of clinical significance].

The clinical significance of serum sialyl SSEA-1 antigen was evaluated using the sera of 1261 patients with malignant tumors and 717 patients with non-malignant diseases measured with Otsuka Assay Laboratories' RIA Kits. The results indicate that the antigen was frequently elevated in the sera from the patients with various adenocarcinomas, including lung (45%), pancreas (64%) and ovary (57%). The false positive incidence of antigens in the sera from the patients with non-malignant disorders was as low as 4.9%. No correlation was observed with other tumor markers examined in this study, and the diagnostic efficiency increased significantly by the combined determination of sialyl SSEA-1 antigen level with other markers. The serial determination of the serum sialyl SSEA-1 antigen level has a clinical utility also in monitoring the patients with adenocarcinoma receiving surgical operation and/or chemotherapy as indicated by the results of the longitudinal observation of the patients.