P53 EXPRESSION IS OF INDEPENDENT PREDICTIVE VALUE IN LYMPH NODE-NEGATIVE BREAST-CARCINOMA

The aim of this study was to evaluate p53 expression, determined by im munohistochemistry, in 151 infiltrating ductal breast carcinomas with negative axillary lymph nodes, and to determine whether p53 can be con sidered as an independent prognostic value for overall and disease-fre e survival. A monoclonal antibody (DO-7) that reacts with an epitope o n the N terminal portion of the human protein p53 was used to detect p 53 in paraffin-embedded sections, utilising a standard avidin-biotin-p eroxidase complex (ABC) technique with a microwave oven antigen retrie val. Overexpression of p53 (more than 50% of stained cells) was found in 45 cases (30%). Forty-five cases were negative and occasionally or moderately stained cells were present in 61 cases. p53 protein overexp ression was significantly associated with high histological grade and tumour necrosis, high MIB-1 value (MIB-1>30%) and negative oestrogen r eceptor status. Univariate analysis (log-rank) showed a shorter overal l survival (P=0.003) in patients with high tumour p53 positivity. This statistical significance was also seen on multivariate analysis (Cox' s logistic regression, P=0.004). p53 protein overexpression is an inde pendent prognostic marker in node-negative breast carcinoma for overal l survival and should be used with other prognostic factors. (C) 1997 Published by Elsevier Science Ltd.