Synovial sarcoma: a new approach to the histological classification and a comparison with malignant mesothelioma. Immunohistochemical study with anti-mesothelial cell serum

Routine paraffin-embedded sections from synovial sarcomas in 70 patients were stained immunohistochemically with monoclonal anti-cytokeratin antibody and serum against mesothelial cells. Positive reactions occurred in the epithelioid cells of biphasic tumors only. On the ground of the reaction with anti-mesothelial serum a hypothetical scheme of cell differentiation in synovial sarcoma was set up.