ESTRO 2025 - Abstract Book

S600

Clinical - Breast

ESTRO 2025

References: 1- ESTRO. Using the axillary vein & artery to validate metrics for high tangents within the POSNOC trial (2023). Available from: https://www.estro.org/Congresses/ESTRO 2023/1388/technicalimprovementsinradiotherapypractice/12829/usingtheaxillaryvein-arterytovalidatemetricsforhig 2- Offersen BV, Boersma LJ, Kirkove C, Hol S, Aznar MC, Biete Sola A, Kirova YM, Pignol JP, Remouchamps V, Verhoeven K, Weltens C, Arenas M, Gabrys D, Kopek N, Krause M, Lundstedt D, Marinko T, Montero A, Yarnold J, Poortmans P.Radiother Oncol. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer. Radiother Oncol 2015, 114(1):3-10

3815

Digital Poster Is Radiotherapy Safe? Assessing Cardiotoxicity in Breast Cancer Treatments

Darwin Pozo Jiménez, Paola Anna Jablonska, Ignacio Visus Fernandez De Manzanos, Irene Martinez Montesinos, Lucia Biscari Garcia, Ana Manterola Burgaleta, Laura Bragado Alvarez, Mario Martin Veganzones, Rodrigo Astudillo Olalla, Sara Lopez Garcia, Libe Amondarain Elgarresta, Ujue Ruiz, Elena Villafranca Iturre Radiation Oncology, Navarra University Hospital, Pamplona, Spain Purpose/Objective: To evaluate the incidence of cardiotoxicity in breast cancer (BC) patients treated with external beam radiotherapy (EBRT), analysing its association with treatment laterality, use of the breath-hold (BH) technique, and subsequent need for cardiological assessment. Material/Methods: A retrospective study was conducted in our institution. Patients’ characteristic, treatment laterality, use of BH technique and fractionation scheme were recorded. Cardiotoxicity was assessed by reviewing patients’ charts since the end of EBRT for new cardiological consultations (CC), new cardiological diagnosis (CD) (cardiac arrhythmia and insufficiency, valvular pathology, cardiomyopathy, ischemic heart disease, cardiac conduction disorder and pericarditis), as well as new cardiological treatment(CT), defined as prescription of beta-blockers, antiarrhythmics, antihypertensives, anticoagulants, diuretics, vasodilators, calcium antagonists, antiplatelets, statins, and cardiac stimulants. Variables were summarised using contingency tables. Proportions were compared using Pearson and Fisher Chi-Square tests for categorical variables. SPSS v.25 was used for statistical analysis. Results: A total of 2,424 BC patients with a median follow-up of 76 months (9-153) were treated between 2012-2018 in our institution. Mean age was 58 years (28-95). A progressive increase in hypofractionation was observed from 2012(4.19%) to 2018 (82.61%). Left breast (LB) tumours accounted for 51.16% cases. BH technique was used in 160 patients (6.60%). CC were required in 418 patients (17.24%), with no statistical differences between LB(8.83%) and RB (8.42%) [p=ns]. New CD were recorded in 274 cases (11.30%), with no statistical differences between LB (5.49%) and RB (5.82%). A total of 1,253 patients (51.69%) were prescribed new CT, and no statistical differences were found between LB (26.65%) and RB (25.04%).