There is an increasing trend to administer adjuvant therapy to patients with all stages of primary breast cancer. However, since only about half of these patients will eventually relapse, it would be useful to have a set of factors that could predict which patients are at high risk for recurrence and which patients are probably cured by local therapy alone.

Using tumour specimens from our San Antonio Tumour Bank, we have confirmed the prognostic significance of axillary nodal status for predicting disease-free and overall survival. Among patients with node-positive disease, both oestrogen-receptors (ER) and progesterone-receptors (PgR) are predictive of patient outcome, but PgR is the more powerful factor. Using multivariate techniques, we have found that amplification and/or expression of the HER-2/neu oncogene provides additional prognostic information for node-positive patients.

Among patients with node-negative disease, ER and tumour size comprise a powerful set of prognostic factors. But ploidy status and S-phase fraction, as measured by flow cytometry, provide additional independent information for predicting disease-free and overall survival. Using these factors, sub-groups of node-negative patients with low risk of recurrence who will probably not benefit from adjuvant systemic therapy might be identified.