ESTRO 2023 - Abstract Book

S529

Sunday 14 May 2023

ESTRO 2023

Conclusion Our results suggest the possibility that early cardiac hospitalization post-RT can be minimized by prioritizing dose reduction to the combined structure and provides a further rationale to avoid dose to the base of the heart, where these structures are located. This is so far the biggest single cohort study linking substructure dose to cardiac related hospitalization post- RT. Patients with history of cardiac admission should be monitored closely. MO-0639 Variation in planned heart radiation dose in 5806 breast cancer patients in 2008-2014: A DBCG study E.R. Skarsø 1,2 , L.H. Refsgaard 3,2 , A. Saini 4 , E.L. Lorenzen 5 , E. Maae 6 , E. Yates 7 , I. Jensen 8 , K. Andersen 9 , K. Boye 10 , L.W. Matthiessen 9 , M. Maraldo 10 , M. Berg 6 , M.H. Nielsen 11 , M. Møller 8 , S.A. Al-Rawi 4 , B. Offersen 3,7,1,2 , S.S. Korreman 1,2,7 1 Aarhus University Hospital, Danish Center for Particle Therapy, Aarhus, Denmark; 2 Aarhus University, Department of Clinical Medicine, Aarhus, Denmark; 3 Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus, Denmark; 4 Zealand University Hospital, Department of Clinical Oncology and Palliative Care, Næstved, Denmark; 5 Odense University Hospital, Laboratory of Radiation Physics, Odense, Denmark; 6 Vejle Hospital, University Hospital of Southern Denmark, Department of Oncology, Vejle, Denmark; 7 Aarhus University Hospital, Department of Oncology, Aarhus, Denmark; 8 Aalborg University Hospital, Department of Oncology, Aalborg, Denmark; 9 Herlev and Gentofte Hospital, Department of Oncology, Herlev, Denmark; 10 Copenhagen University Hospital – Rigshospitalet, Department of Oncology, København, Denmark; 11 Odense University Hospital, , Department of Oncology, Odense, Denmark Purpose or Objective In this study, 5806 patients from the Danish Breast Cancer Group (DBCG) RT Nation cohort were collected, with the aim of verifying the effect of DBCG cardiac related guidelines. We evaluated use of gating, dose to the heart and use of different structures for heart avoidance in treatment planning. Materials and Methods We included clinical structure sets, dose plans and CT scans from 5806 high-risk breast cancer (BC) patients treated with adjuvant radiotherapy (RT) across the nation during 2008-14. To ensure consistency in reporting heart dose, an in-house developed deep learning (DL) model was used to segment heart structures for all patients.