PROGNOSTIC-SIGNIFICANCE OF C-ERBB-2 NEU AMPLIFICATION AND EPIDERMAL GROWTH-FACTOR RECEPTOR (EGFR) IN PRIMARY BREAST-CANCER AND THEIR RELATION TO ESTRADIOL-RECEPTOR (ER) STATUS/

The aim of this study is to evaluate the prognostic significance of c- erbB-2/neu amplification and epidermal growth factor receptor (EGFR) e xpression in primary breast cancer (BC) and their prognostic implicati ons when combined with estradiol receptor (ER) status. In this work, 8 25 BCs were studied. Neu amplification was evaluated by dot-blot and E GFR expression was evaluated by ligand binding assay using I-125-EGF. Neu, EGFR, estradiol and progesterone receptors (ER and PR) had a mark ed influence on disease free survival (DFS) in univariate analysis. In node-negative (NO) cases only neu was associated with short DFS (p=0. 005). However, in node-positive (N +) cases both EGFR (p=0.005) and ne u (p=0.002) influenced DFS. None of the biological markers were signif icant predictors for overall survival (OS) in NO/BC.. On the contrary, in N +/BC, EGFR + (p=0.003) was associated with short OS. The EGFR +/ neu + phenotype represented a sub-group with an even worse prognosis w ith respect to DFS (p=0.0034) as well as EGFR+/ER- tumors (p=0.005). M oreover, neu+/ER-patients also had a high probability of relapse (p=0. 0000) and death (p = 0.006). C-erbB-2/neu, EGFR, histological grade, p N, pT and ER were subjected to a Cox multivariate regression analysis: neu was the most important parameter in predicting recurrence, and EG FR was a significant predictor for OS. (C) 1997 Elsevier Science B.V.