The immunocytochemical demonstration of basement membrane deposition in transitional cell carcinoma of bladder.

We assessed the staining characteristics of the basement membrane of transitional cell carcinoma of bladder using a monoclonal antibody to type IV collagen. Basement membranes were clearly stained at the stromal/carcinoma interface. As transitional cell carcinoma became less well differentiated and the depth of invasion increased interruptions to basement membrane staining became more extensive and these findings are comparable to those described in similar series of transitional cell carcinoma using polyclonal antibodies to type IV collagen. The defects in basement membrane staining may be related to the degree and direction of tumour cell differentiation or may be explained by increased degradation compared to synthesis of basement membrane components. Demonstration of the basement membrane may be of value in diagnostic histopathology as a marker of the biological behaviour of transitional cell carcinoma of bladder.