PROGNOSTIC-SIGNIFICANCE OF THE COEXPRESSION OF P53 AND C-ERBB-2 PROTEINS IN BREAST-CANCER

The immunohistochemical expression of p53 and c-erbB-2 gene proteins w as examined in a series of 130 breast adenocarcinomas. This study inte nded to investigate whether the frequency of the altered expression of the tumour suppressor gene p53 and the overexpression of the oncogene c-erbB-2 in breast cancer tissue cells correlated with other variable s known to affect the biological behaviour of these tumours and the ov erall survival of the patients (median follow-up time: 6 Sears), The e xpression of p53 protein and c-erbB-2 gene product was evaluated immun ohistochemically, Expression of p53 protein was detected in 30 (23 per cent) of the neoplasms examined, while 26 (20 per cent) out of the 13 0 cases demonstrated positive c-erbB-2 immunoreactivity. There was a s tatistically significant association between p53 protein expression an d primary tumour size, lymph node involvement, and oestrogen receptor positivity, The incidence of c-erbB-2 positivity was significantly cor related with high tumour grade, axillary node invasion, large tumour s ize, and the absence of steroid receptors, p53 immune-expression was c learly associated with c-erbB-2 protein overexpression, Concomitant p5 3 and c-erbB-2 positive immunolabelling, which emerged in 14 out of th e 130 cases (10.7 per cent), was clearly associated with high grade, l arge size, positive nodal status, ductal infiltrating (NOS) histologic al type, and low values of progesterone receptors, Overall survival of patients was not significantly related to the immunoreactivity of eit her p53 or c-erbB-2 considered separately, whereas there was a clearly significant trend to worse overall prognosis in cancers with double p 53/c-erbB-2 positive phenotype, The simultaneous immunodetection of p5 3/c-erbB-2 appears to have greater negative prognostic relevance than their separate expression.