The overexpression of the Human Epidermal Growth Factor Receptor 2 (HER2) is observed in 15% of breast cancers and associated with poor prognosis in terms of overall survival. Trastuzumab is an anti-HER2 targeted therapy, leading to a specific inhibition of the molecular mechanisms triggered by this receptor. In an adjuvant setting, trastuzumab and radiotherapy have each proved their oncologic efficacy in the management of the breast tumours presenting this molecular profile. However, both treatments expose to an increased risk of toxicities, particularly cardiovascular ones. Moreover, the radiosensitizing effect of trastuzumab has been proved in vitro and in vivo. Hence, in clinical practice, the benefit/risk ratio of a concurrent treatment remains to be defined. This literature review has for purposes to describe the rationale making conceivable the administration of trastuzumab concurrently with locoregional breast radiotherapy, and to remind the results of the clinical studies having assessed this therapeutic association.
Keywords: breast cancer; concurrent treatment; literature review; radiotherapy; trastuzumab.