Primary chemotherapy or hormonotherapy for patients with breast cancer

Scientific rationale for primary treatment of breast cancer relies on experimental data showing that the incidence and growth of disease correlate with the primary tumour mass and tumoral angiogenesis. Although the strategy may be applied to both chemotherapy and hormonotherapy, only the first was extensively explored for patients with locally advanced breast cancer in order to improve survival and to avoid mastectomy through the achievement of a downstaging of the tumour. Encouraging results obtained in this clinically advanced setting combined with renewed interest for tumoral angiogenesis brought clinicians to apply this strategy to smaller tumours. Despite high clinical and 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 recent developments in chemotherapy. Of 6 published randomized trials comparing primary vs adjuvant chemotherapy, none showed any significant impact of primary chemotherapy on survival, with a trend towards delayed/less distant recurrences in patients treated by primary chemotherapy in some. Some recent reports suggest that local relapse rate might be increased after conservative treatment following induction chemotherapy in subgroups analyse and this should cause oncologists to revise and define the role for conservative surgery after primary medical treatment 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 patient populations submitted to primary medical treatment.