ESTRO 2025 - Abstract Book

S4024

Radiobiology - Tumour radiobiology

ESTRO 2025

Conclusion: Faster Truebeam delivery times resulted in mean BEDs significantly greater than either Cyberknife or GK. Therefore, we conclude that linac-based SRS delivers an effectively hotter treatment compared to these platforms for the same physical dose. Additional margins can exaggerate the BED differential further, increasing toxicity risk to critical structures. These results provide critical guidance to clinicians who may migrate SRS to linac-based systems.

Keywords: BED, SRS, Schwannoma

References: 1. Benedict SH, Lin PS, Zwicker RD, Huang DT, Schmidt-Ullrich RK. The biological effectiveness of intermittent irradiation as a function of overall treatment time. Int J Radiat Oncol Biol Phys. 1997 37(4):765-769 2. Wang X, Xiong XP, Lu J, Zhu GP, He SQ, Hu CS, Ying HM. The in-vivo study of the radiobiological effect of prolonged delivery time to tumor control in C56BL mice implanted with Lewis lung cancer. Radiat Oncol. 2011 Jan 12:6:4 3. Jones B, Hopewell JW, Paddick I, Lindquist C, Nordstrom H, Lidberg P, Garding J. The role of the concept of biologically effective dose (BED) in treatment planning in radiosurgery. Physica Medica 2015 31:627:633

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Digital Poster Meta-analysis of publicly available transcriptomics data reveals predictive biomarkers for neoadjuvant chemoradiotherapy in rectal cancer Aleksandra Stanojevic 1 , Rafael Stroggilos 2 , Mladen Marinkovic 3,4 , Suzana Stojanovic-Rundic 3,4 , Radmila Jankovic 1 , Sergi Castellvi-Bel 5 , Remond J.A. Fijneman 6 , Antonia Vlahou 2 , Jerome Zoidakis 2,7 , Milena Cavic 1 1 Department of Experimental Oncology, Institute for Oncology and Radiology of Serbia (IORS), Belgrade, Serbia. 2 Department of Biotechnology, Biomedical Research Foundation, Academy of Athens (BRFAA), Athens, Greece. 3 Clinic for Radiation Oncology and Diagnostics, Department of Radiation Oncology, Institute for Oncology and Radiology of Serbia (IORS), Belgrade, Serbia. 4 Faculty of Medicine, University of Belgrade, Belgrade, Serbia. 5 Gastroenterology Department, Fundació Clínic per la Recerca Biomèdica-Institut d’Investigacions Biomèdiques August Pi i Sunyer (FRCB-IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Hospital Clínic, University of Barcelona, Barcelona, Spain. 6 Department of Pathology, Netherlands Cancer Institute Antoni van Leeuwenhoek Ziekenhuis (NKI AVL), Amsterdam, Netherlands. 7 Department of Biology, National and Kapodistrian University of Athens, Athens, Greece