ESTRO 2025 - Abstract Book

S2598

Physics - Detectors, dose measurement and phantoms

ESTRO 2025

3D printed components, dosimetric gel and in target center positioned radiochromic films were irradiated with one fraction dose and compared with planned in TPS. It was estimated phantom components and dose gel densities similarity to patient's tissues in Hounsfield units (HU). All structures met requirements: phantom (plastic/bone) 187HU, target 152HU, gelatin 10-15HU. Gamma passing rate was 95.7% to radiochromic films, 96.8% to dosimetric gels. During TP comparison (Eclipse/Monaco) was found that using SMART treatment method is possible to reduce treatment volume at least 15%. Conclusion: SMART treatment integration into clinical practice could improve access to services for cancer patients, shorten the duration of treatment, preserve laryngeal function, and protect organs at risk. Study is supported by the Research Council of Lithuania S-MIP-24-66. References: 1. Cancer Today – IARC, internet access: https://gco.iarc.fr/today/home; 2. Arboleda LPA, Neves AB, et all. Overview of glottic laryngeal cancer treatment recommendation changes in the NCCN guidelines from 2011 to 2022. Cancer Rep (Hoboken). 2023;6(8): e1837; 3. Yoo J, Lacchetti C, Hammond JA, Gilbert RW; Head and Neck Cancer Disease Site Group. Role of endolaryngeal surgery (with or without laser) versus radiotherapy in the management of early (T1) glottic cancer: a systematic review. Head Neck. 2014;36(12):1807-19; 4. Application of 3D gel dosimetry as a quality assurance tool in functional Leksell Gamma Knife radiosurgery / L.Kudrevicius, E.Jaselske et all. 2022;vol. 8, iss. 2, art. no. 69, p. 1-15. Keywords: dosimetry, individualized phantom, MR-Linac

2098

Digital Poster Modeling and validation of a rotative over-couch support transmission and attenuation properties for TBI VMAT Susana Gonçalves 1,2,3 , Luís Cunha 1,2 , Diana Pinto 1,2 , Joana Lencart 1,2 , Anabela G Dias 1,2 1 Medical Physics Department, Portuguese Oncology Institute of Porto (IPO-Porto), Porto, Portugal. 2 Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Centre (CI-IPO), Portuguese Oncology Institute of Porto (IPO-Porto), Porto Comprehensive Cancer Center (Porto.CCC) & Rise@CI-IPOP (Health Research Network), Porto, Portugal. 3 Escola Internacional de Doutoramento, Universidad de Vigo, Vigo, Spain Purpose/Objective: VMAT is a promising technique for Total Body Irradiation, but its main challenge remains on the limited longitudinal couch movement for patient positioning and irradiation. Rotational couches can be used, which enable safe and