ESTRO 2024 - Abstract Book

S652

Clinical - Breast

ESTRO 2024

2553

Digital Poster

Locoregional hypofractionated radiotherapy and T-DM1 in breast cancer: a single center experience

Giuseppina Apicella 1 , Claudia Scaringi 1 , Elisabetta Ponti 1 , Angela Damiana Andrulli 1 , Rosamaria Adorisio 2 , Leopoldo Costarelli 3 , Mauro Minelli 4 , Lucio Fortunato 5 , Daniela Musio 1 1 San Giovanni Addolorata, Radiation Oncology, Rome, Italy. 2 San Giovanni Addolorata, Pharmacy, Rome, Italy. 3 San Giovanni Addolorata, Pathology, Rome, Italy. 4 San Giovanni Addolorata, Medical Oncology, Rome, Italy. 5 San Giovanni Addolorata, Surgery, Rome, Italy

Purpose/Objective:

The standard care of patients with breast HER2+ disease is neoadjuvant chemotherapy with HER2-targeted therapy. Adjuvant radiotherapy (RT) remains a milestone of treatment, with volumes depending on surgery type and on the presence of high-risk factors. According to Katherine trial [1] adjuvant Trastuzumab-emtansine (TDM1) must be administered during the RT course to all patients with residual disease. Moderate hypofractionation represents the standard of care for whole-breast radiotherapy, and encouraging results regarding simultaneous integrated boost (SIB) on tumor bed and hypofractionation for regional nodes irradiation are available in literature [2].

Our aim was to examine the incidence of acute side effects following the concurrent use of hypofractionated RT and T-DM1 therapy.

Material/Methods: