Immunohistochemical demonstration of tumor-associated antigens with the aid of monoclonal and polyclonal antisera in carcinoma of the bladder.

Keratin was identified with the aid of polyclonal antisera in the cytoplasm in over 90% of the transitional cell carcinomas investigated. The intensity of staining increased with the degree of dedifferentiation. Detection of cytokeratin with monoclonal antibodies was successful in over 80% of samples. All squamous cell carcinomas of the bladder were strongly positive for keratin and cytokeratin. CEA was found in 20% of the G1 and 40% of the G2 and G3 carcinomas of the bladder. Both the prostatic epithelium markers PSA and PAP and the monoclonal antibody Ca1 were negative in all cases.