Use of immunohistochemically demonstrated c-erb B-2 oncoprotein expression as a prognostic factor in transitional cell carcinoma of the urinary bladder.

Formalin-fixed, paraffin-embedded specimens from 91 primary transitional cell cancers (TCC) of the urinary bladder were stained with a monoclonal antibody to c-erb B-2 oncoprotein. Twelve percent (11/91) of the TCC stained for c-erb b-2 oncoprotein, and in 4% (4/91) of cases, the expression was graded as moderate or heavy. The expression of c-erb B-2 was significantly (p = 0.072) related to the WHO grade, whereas no significant difference in its expression was found between (a) the superficial and invasive TCC and (b) between the papillary and nonpapillary TCC. One of the tumours had a verified metastasis at the time of diagnosis and it exhibited heavy expression of c-erb B-2. The expression of c-erb B-2 was significantly related to the number of nucleolar organiser regions/TCC nucleus (p = 0.003). Aneuploid TCC were more frequently associated with moderate or heavy expression of c-erb B-2 than the diploid ones. Recurrence and progression of TCC could not be significantly related to expression of c-erb B-2 oncoprotein. In survival analysis, moderate and heavy expression of c-erb B-2 were related to poor prognosis (p = 0.032) during a mean follow-up time of 14 years. In conclusion, moderate and heavy expression of c-erb B-2 oncoprotein in TCC seems to be related to more aggressive behaviour whereas low expression of this oncoprotein had no predictive value. No evidence was obtained, however, that the expression of c-erb B-2 concoprotein alone would determine the biological behaviour of TCC.