ESTRO 2024 - Abstract Book

S640

Clinical - Breast

ESTRO 2024

1) J. O. Archambeau, et al, Pathophysiology of irradiated skin and breast. International Journal of Radiation Oncology* Biology* Physics, 31(5):1171 – 1185, 1995.

2) T. Liu, et al, Measurements of radiation-induced skin changes in breast- cancer radiation therapy using ultrasonic imaging. In 2008, International Conference on BioMedical Engineering and Informatics, volume 2, pages 718 – 722. IEEE, 2008. 3) FA Hussein et al, Ultrasonographic Evaluation of Skin Toxicity Following Radiotherapy of Breast Cancer: A Systematic Review. Int J Environ Res Public Health. 2022 Oct 18;19(20):13439. doi: 10.3390/ijerph192013439. PMID: 36294025; PMCID: PMC9603505.

4) M. Avanzo et al. Prediction of skin dose in low-kv intraoperative radiotherapy using machine learning models trained on results of in vivo dosimetry. Medical physics, 46(3):1447 – 1454, 2019.

5) Iacovacci J et al. Dependence of the AUC of NTCP models on the observational dose range highlights cautions in comparison of discriminative performance. Phys Med. 2023 Sep;113:102654. doi: 10.1016/j.ejmp.2023.102654. Epub 2023 Aug 12. PMID: 37579522. The study was supported by AIRC (Associazione Italiana per la Ricerca sul Cancro), IG25951 and IG23150 grants and by Fondazione Regionale per la Ricerca Biomedica, project nr. 110 - JTC PerPlanRT ERA PerMed, GA779282. D Raspanti of Tema Sinergie is gratefully acknowledged for support in the use of MIM and MIMassistant software.”

2330

Digital Poster

DOSIMETRIC COMPARISON OF HEART SUBSTRUCTURES FOR DIBH BETWEEN FREE BREATHING FOR BREAST CANCER

Ingrid Romera-Martínez 1,2 , Irene Oliveras 3 , Maria Buxó 4 , Joan Martínez 4 , Rafel Fuentes Raspall 3,2 , Arantxa Eraso Urien 3,2 , Elisabeth Pinart Nadal 5 , Joan Carles Vilanova 6 1 Institut Català d'Oncologia (ICO), Medical Physics and Radiation Protection, Girona, Spain. 2 Girona Biomedical Research Institute (IDIBGI), ONCORFIM Group, Girona, Spain. 3 Institut Català d'Oncologia (ICO), Radiation Oncology, Girona, Spain. 4 Girona Biomedical Research Institute (IDIBGI), Statistics Deparment, Girona, Spain. 5 University of Girona, Medicine Faculty, Girona, Spain. 6 Clinica Girona, Radiology, Girona, Spain

Purpose/Objective:

Nowadays, radiotherapy increases cure rates in breast cancer. However, cardiac exposure in left sided tumours, might increase cardiotoxicity. Deep inspiration breath hold (DIBH) allows separate the planning target volumes (PTV) of the heart. Advanced dosimetric techniques as volumetric modulated arc therapy (VMAT) or hybrid plans (H VMAT) reduced heart doses. Duane et al (1) describes the methodology to delineate the heart substructures in planning radiotherapy CT. The relationships between doses to different heart substructures and subsequent injury of these structures have not yet been investigated. The aim of this study is to compare dosimetric parameters of