An expression of squamous cell carcinoma-related antigen in oral cancers

The relationship between serum level and stainability of squamous cell carcinoma-related antigen (SCC-Ag) in carcinoma of the oral cavity was examined. The amount of serum SCC-Ag was measured in 60 of 97 patients by a radioimmunoassay system. 63.3% showed elevated serum SCC-Ag levels above 2.0 ng/ml. The specimens taken from 97 patients with oral squamous cell carcinoma (SCC) were stained with a monoclonal antibody against the SCC-Ag by using an immunoperoxidase method. Tumor cells with keratinization in well-differentiated SCC stained well with the antibody, whereas cells without keratinization in poorly-differentiated SCC stained weakly, or not at all. Serum levels of the antigen were significantly higher in cases of invasive cancers, but serum levels of antigen correlated with neither the degree of morphological differentiation of the tumor, nor with the intracellular content of the antigen. These observations suggest that the parenchymalstromal relationship is one of the decisive factors in determining the serum SCC-Ag level.