ESTRO 2025 - Abstract Book

S3620

Physics - Quality assurance and auditing

ESTRO 2025

Conclusion: EPID-based IVD is a feasible and effective QA tool for CBCT-based oART, complementing vendor-provided methods. It improves detection of beam delivery deviations and anatomical changes, enabling tighter gamma criteria due to the exclusion of inter-fractional variations. Routine integration of EPID IVD could enhance QA in oART workflows, provided that technical barriers, such as automation of image retrieval and analysis, are addressed.

Keywords: in-vivo dosimetry, EPID, adaptive radiotherapy

References: [1] Med Phys. 2023;50:e865–e903.

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Poster Discussion Development and clinical implementation of patient-specific quality assurance for Lattice Radiation Therapy Makan Farrokhkish 1 , Veng Jean Heng 1,2 , Jan Seuntjens 1,3 , Ming Liu 1 , Harald Keller 1,3 , Amy Parent 1 , Yat Tsang 1 , Jelena Lukovic 1,3 , Monica Serban 1,3 1 Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Canada. 2 Department of Radiation Oncology, Stanford University, Stanford, USA. 3 Department of Radiation Oncology, University of Toronto, Toronto, Canada Purpose/Objective: To establish patient specific quality assurance (PSQA) for bulky tumors treated with Lattice Radiotherapy (LRT), and to evaluate the accuracy and deliverability robustness of VMAT-based LRT across various lattice configurations and dose prescription protocols. Material/Methods: A total of 10 patients with various tumor sites and gross tumor volume (GTV) ranging from 139cm 3 to 3183cm 3 were planned with LRT using the RayStation Treatment Planning System (Figure1a). Depending on patient’s GTV