ESTRO 2025 - Abstract Book

S3591

Physics - Quality assurance and auditing

ESTRO 2025

Conclusion: We successfully implemented an automated QA system and carried out prospective central case review for all patients in the experimental arm of the hypo-FLAME 3.0 trial.

Keywords: Clinical trial, prostate cancer, quality assurance

References: 1) Zhong et al. Clinical Impact of Contouring Variability for Prostate Cancer Tumor Boost. Int J Radiat Oncol Biol Phys. 2024 Nov 15;120(4):1024-1031. doi: 10.1016/j.ijrobp.2024.06.007 2) van Schie et al. Contouring of prostate tumors on multiparametric MRI: Evaluation of clinical delineations in a multicenter radiotherapy trial. Radiother Oncol. 2018 Aug;128(2):321-326. doi: 10.1016/j.radonc.2018.04.015.

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Digital Poster The role of the Off-Axis Winston-Lutz test in routine modern linear accelerator quality assurance. Joel Poder 1,2,3 , Harry Porter 1 , Ryan Brown 1 , Robert Chambers 1 , Andrew Howie 1 1 Medical Physics, St George Cancer Care Centre, Kogarah, Australia. 2 Institute of Medical Physics, University of Sydney, Camperdown, Australia. 3 Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia Purpose/Objective: Over the past decade, the use of multiple-target single-isocenter (MTSI) stereotactic radiosurgery (SRS) with linear accelerators (linacs) has grown substantially [1]. Errors in mechanical axes of linacs can affect the accuracy of off axis target positioning in such plans [2]. The off-axis Winston-Lutz test (OAWLT) is effective in identifying these