ESTRO 2025 - Abstract Book

S3732

Physics - Radiomics, functional and biological imaging and outcome prediction

ESTRO 2025

Conclusion: T2-mapping showed potential in identifying RP patients and in providing an initial segmentation of the RP-affected lung area.

Keywords: radiation-induced pneumonitis, T2-maps, MR-Linac

References: 1. Shioya S, et al. Tissue characterization of pneumonia and irradiated rat lungs with magnetic resonance relaxation times. Magn Reson Imaging. 1994;12(5):799-803. 2. Buzan MT, et al. T2 mapping of CT remodelling patterns in interstitial lung disease. Eur Radiol . 2015;25(11):3167 3174. 3. Benlala I, et al. Quantification of MRI T2 Interstitial Lung Disease Signal-Intensity Volume in Idiopathic Pulmonary Fibrosis: A Pilot Study. J Magn Reson Imaging. 2021;53(5):1500-1507

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Digital Poster Prostate R2* measurements on an MR-Linac are repeatable and sensitive to treatment-induced changes Chris Moore 1,2 , Asher Ezekiel 1 , Ereny Saad 3 , Martin Swinton 2,3 , David L Buckley 4 , Ananya Choudhury 2,3 , Cynthia L Eccles 2,5 , Peter Hoskin 2,3 , Michael J Dubec 1,2 , Damien J McHugh 1,2 1 Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Manchester, United Kingdom. 2 Division of Cancer Sciences, University of Manchester, Manchester, United Kingdom. 3 Clinical Oncology, The Christie NHS Foundation Trust, Manchester, United Kingdom. 4 Biomedical Imaging, University of Leeds, Leeds, United Kingdom. 5 Radiotherapy Services, The Christie NHS Foundation Trust, Manchester, United Kingdom Purpose/Objective: There is a need for robust imaging biomarkers [1] of radiotherapy response in prostate cancer. Through its sensitivity to deoxyhaemoglobin, the effective transverse relaxation rate R2* (1/T2*) from blood oxygen level dependent (BOLD) MRI is a potential quantitative imaging biomarker of hypoxia [2], which is known to negatively affect outcomes for prostate cancer patients [3]. This work extends initial findings [4] to evaluate the repeatability of prostate R2* measurements on an MR-Linac and assess sensitivity to treatment-induced changes.