EXPRESSION OF C-ERBB(2) CORRELATES WITH TUMOR STAGE AND GRADE IN SUPERFICIAL TRANSITIONAL-CELL CARCINOMA OF THE URINARY-BLADDER (TCC)

To evaluate the role of c-erbB(2) and p53 overexpression in superficial bladder carcinoma confined to the submucosa in regard to other pathohistological data, this study was performed. Methods: Paraffin-embedded tissue samples of 84 patients with TCC (stage Ta: 43 cases, stage T1: 41 cases), treated with transurethral resection including bladder mapping (RO) were examined immunohistochemically using antibodies against p53 and c-erbB(2). In 20 of these cases, semiquantitative protein analysis, using Immunoblot techniques, was performed for quality control. For c-erbB(2) only membrane staining, for p53 nuclear staining alone was considered to be positive. Results: p53 immunostaining was detected in 69/84 (82%) of all cases examined, c-erbB(2) positivity could be diagnosed in 40/84 (48%) tumors. Overexpression of c-erbB(2) was significant more often in T1 tumors than in Ta tumors and also more frequent in G2 and G3 than in G1 tumors. The immunostaining for p53 correlated with tumor grade, but not with stage of disease. Conclusions: These results indicate, that c-erbB(2) and also p53 may serve as an additional marker of tumor cell differentiation in early bladder carcinomas and the expression of c-erbB(2) seems to be of value in predicting the tumor stage (Ta versus T1) at time of diagnosis or initial treatment.