Immunohistochemical overexpression of C-erbB-2 in the prognosis of breast cancer.

Immunohistochemical c-erbB-2 protein overexpression was detected in 34 of 124 (27.4%) paraffin-embedded breast cancer specimens. Although no difference was seen between the c-erbB-2 positive and negative groups in 5-year disease-free survival, 5-year overall survival was significantly less favorable in the c-erbB-2 positive group. Furthermore, patients graded as having positive c-erbB-2 staining and aneuploid DNA showed significantly poorer survival than those in other categories. The significant prognostic factors, determined by a multivariate analysis, were nodal status and c-erbB-2 overexpression. Our findings therefore suggest that c-erbB-2 expression is a prognostic factor in breast cancer and that it could be useful in the determination of postoperative adjuvant therapy.