An induction chemotherapy, before any local treatment, allows to precise the chemosensitivity of the primary tumor. These data may help to improve indication and type of a further adjuvant chemotherapy. However there are many biological differences between different sites of the same tumor and along the time, without or after treatment. It is thus impossible to be sure that a chemotherapeutic regimen effective as first treatment on the primary will be equally active on micro-metastases some months later. Many questions in this field will be answered only by controlled studies and careful observations.