John Libbey Eurotext

Innovations & Thérapeutiques en Oncologie


Combining radiotherapy and targeted therapy to treat breast cancer Volume 8, issue 4, July-August 2022

1 Institut Curie, Université PSL, Université Paris Saclay, Inserm LITO, 91898 Orsay, France
2 Institut Curie, Université PSL, Département d’oncologie radiologique, Centre de protonthérapie, Centre universitaire, 91898 Orsay, France
3 Institut Curie Département d’oncologie médicale, 26, rue d’Ulm, 75005 Paris, France
4 Institut Curie, Université PSL, Département d’oncologie radiologique, 26, rue d’Ulm, 75005 Paris, France
Tirés à part : A. Beddok
Remerciements et autres mentions :
Financement : aucun.
Liens d’intérêts : les auteurs déclarent ne pas avoir de lien d’intérêt.


The aim of this article is to take stock of current knowledge on the combination of radiotherapy (RT) and targeted treatments which are the most widely used or under development for the treatment of breast cancer.


Preclinical and clinical studies on this combination of treatment were identified and analysed in detail.


Several studies have shown that the combination of RT and tamoxifen increases the risk of radio-induced pulmonary toxicity. Consequently, the two treatments should not be administered at the same time. The combination of HER2 inhibitors (trastuzumab, pertuzumab) and RT appears to be safe. However, trastuzumab emtasine (T-DM1) should not be administered at the same time as cerebral RT, as this combination may increase the risk of cerebral radionecrosis. The combination of RT with new targeted treatments, such as new selective oestrogen receptor degraders (SERD), lapatinib, cell cycle inhibitors, immune checkpoint inhibitors and molecules acting to repair DNA damage, appears to be a feasible option, but this has essentially been evaluated in retrospective or prospective studies on small numbers of patients. Moreover, these studies are highly heterogeneous in terms of the dose and fractionation used in radiotherapy, the dosage of systemic treatments, and the sequence of treatments used.


The combination of RT and the majority of targeted therapies used to treat breast cancer appears to be well-tolerated (with the exception of tamoxifen), however, these results need to be confirmed in randomised prospective studies.