ESTRO 2025 - Abstract Book

S1647

Clinical – äediatric tumours

ESTRO 2025

Conclusion:

Key findings showed that tumour location, especially in the pelvic and thoracic regions, has a greater impact on set up accuracy than age or anaesthesia. While anaesthesia helps immobilize younger children, it does not significantly improve accuracy or reduce margin size. Tumours in the pelvic and thoracic areas require larger PTV margins and more frequent imaging due to increased motion variability. The study highlights the need for treatment protocols tailored to tumour location to ensure precision and safety in paediatric radiotherapy.

Keywords: paediatric, setup errors, PTV margins

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