ESTRO 2025 - Abstract Book

S3580

Physics - Quality assurance and auditing

ESTRO 2025

Conclusion: The independent dose calculations demonstrate a potential for implementation in PSQA for proton therapy. The results suggest that it is an alternative tool for comprehensive quality assurance program. For reliable treatment verification, careful consideration of confidence limits, tolerance limits, and action limits is recommended.

Keywords: Independent dose calculation, Patient specific QA

References: 1. Ezzell GA, Burmeister JW, Dogan N, et al. IMRT commissioning: multiple institution planning and dosimetry comparisons, a report from AAPM Task Group 119. Medical physics. 2009;36(11):5359-73. doi:10.1118/1.3238104. 2. Zhu TC, Stathakis S, Clark JR, et al. Report of AAPM Task Group 219 on independent calculation ‐ based dose/MU verification for IMRT. Medical physics. 2021;48(10):808-29. doi:10.1002/mp. 15069. 3. Miften M, Olch A, Mihailidis D, et al. Tolerance limits and methodologies for IMRT measurement ‐ based verification QA: recommendations of AAPM Task Group No. 218. Medical physics. 2018;45(4):53-83. doi: 10.1002/mp.12810.

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Proffered Paper Image registration and dose mapping for thoracic reirradiation: Pre-trial quality assurance in the Scandinavian CURE Lung trial Hella Sand 1 , Ane Appelt 2 , Dennis Arp 1 , Maria Fuglsang Jensen 3 , Marianne Marquard Knap 4 , Christina Larsen 5 , Mikkel Drøgemüller Lund 6 , Morten Nielsen 7 , Wiviann Ottosson 5 , Lone Hoffmann 4 1 Department of Oncology, Aalborg University Hospital, Aalborg, Denmark. 2 Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom. 3 Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark. 4 Department of Oncology, Aarhus University Hospital, Aarhus, Denmark. 5 Department of Oncology, Radiotherapy Research Unit, Copenhagen University Hospital - Herlev and Gentofte, Herlev, Denmark. 6 Department of Oncology, Vejle Hospital, University Hospital of Southern Denmark, Vejle, Denmark. 7 Department of Oncology, Odense University Hospital, Odense, Denmark Purpose/Objective: Safe delivery of high-dose reirradiation depends on robust evaluation of previously delivered dose on current patient anatomy, but very little work has been done on standardization and intercentre variation of this process. This study aimed to assess the variability of (1) rigid (RIR) and deformable (DIR) image registration and (2) dose-