[Radiobiology and breast cancer molecular classification: present or future?]

Breast cancer treatment guidelines are based on usual prognostic factors such as size, histological grade, axillar lymph node involvement, expression of hormonal receptors. The intrinsic molecular classification is giving additional information over clinical and pathological features. Predictive models for systemic relapse have been established and are currently under clinical investigation to determine precisely when chemotherapy is needed. This review will look after the implications of this classification in terms of radiobiology: on one hand, we will look if this classification helps for loco-regional relapse prediction and on the other hand, if it is able to change the radiotherapy schedule within the molecular classification.