DNA was extracted from tumour samples of 77 patients with primary breast carcinoma and HER-2 proto-oncogene amplification was assessed. Prognostic indices such as number of positive lymph nodes, tumour size and histological grading were strongly associated with overall survival. No statistically significant correlation between amplification of HER-2 and overall survival was observed. In addition, prognostic indices, HER-2 amplification and disease-free interval was not correlated. Analysis of HER-2 amplification alone is not a useful guide in the management of patients with mammary carcinoma.