[Towards an individualization of systemic treatment of breast tumors]

Clinical trials of adjuvant treatment of breast cancers have been limited for a long time to overall comparisons of heterogeneous populations. A new generation of clinical trials should be implemented, with especially the selection of the patients as a function of the molecular characteristics of their tumour. Unquestionable biological data must be taken into account to raise relevant questions, such as the role of topoisomerase II in the response to anthracyclines or the role of p53 in the response to taxanes. Microarrays technology, which allows the establishment of expression profiles of the whole genome, are very powerful tools which have allowed to reclassify breast tumours and to obtain "molecular signatures" characteristic for the risk of metastatic recurrence. A large randomised prospective study has been recently initiated with the aim of comparing the prognostic value of this signature to that of classical histopathologic criteria. In the next future, it will be possible to consider an individualisation of the prescription of cancer chemotherapies on molecular validated bases.