[Initial medical treatment for breast cancer]

Rationale for primary medical treatment of breast cancer relies on experimental data showing that the incidence of metastatic disease is dependent on the primary tumour mass and tumoral angiogenesis. Although this concept may be applied to both chemotherapy and hormonotherapy, only the first was extensively explored for patients with locally advanced breast cancer, and more recently in smaller tumours. Despite high clinical +/- radiological response rates, only pathologic information, carefully assessed in both the primary and axillae lymph nodes, stands out as the major source of prognostic information on patients' outcome. Recent developments in chemotherapy (dose-intensity, new drugs) do not seem to influence these results, indicating the possible limitations of conventional chemotherapy. Of 6 published randomized trials comparing neo versus adjuvant strategy, none showed any significant impact of primary chemotherapy on survival, with in some a trend towards delayed and/or distant recurrences if neoadjuvant treatment given. That some recent reports suggest that local relapse rate might be increased after conservative treatment following induction chemotherapy in subgroups analyses should cause oncologists to revise the role for post neoadjuvant treatment conservative surgery without calling into question the global strategy. Through sequential samplings, neoadjuvant medical treatment provides indeed the opportunity (a) to identify molecular mechanisms associated with pathologic response and (b) to study the possibility to guide the choices for induction treatment and patients' populations submitted to primary medical treatment.