Prognostic value of HER-23/neu and p53 expression in node-positive breast cancer. HER-2/neu effect on adjuvant tamoxifen treatment

HER-2/neu and p53 expression, conventional clinical and pathologic prognost ic factors, were evaluated in a retrospective series of 283 node-positive b reast cancer patients. Overexpression was determined by immunohistochemistr y in formalin-fixed paraffin-embedded tissue blocks. Twenty one percent wer e HER-2/neu positive and 40% p53 positive. HER-2/neu expression was related to axillary lymph node metastasis (P = 0.014), inflammatory infiltrates (P = 0.004), and the absence of oestrogen (ER) (P = 0.0026) and progesterone (P = 0.01) receptors (PR). p53 expression was related to lymph node involve ment (P = 0.03), necrosis (P = 0.036), absence of ER (P = 0.028) and PR (P = 0.065). p53 was not associated with outcome. HER-2/neu was an unfavourabl e prognostic factor for disease-free (DFS) (P = 0.05) and overall survival (OS) (P = 0.02) in univariate analysis. Multivariate analysis showed that t he number of involved axillary nodes (P < 0.00001), age (P = 0.004), grade (P = 0.04), and PR (P = 0.04) were independent predictors for OS. ER-positi ve patients treated with adjuvant tamoxifen had shorter DFS and OS when the y were HER-2/neu positive. (C) 2000 Harcourt Publishers Ltd.