ESTRO 2025 - Abstract Book

S3311

Physics - Intra-fraction motion management and real-time adaptive radiotherapy

ESTRO 2025

great vessels and lung regions. The HI (Figure 2) varied with the initial phase, showing an increased impact at lower frequencies and fewer fractions.

Conclusion: The operator-free quantification of DIR uncertainties has been successfully integrated into the treatment planning system. The proposed methodology allows clinicians to assess respiratory motion and interplay effect on 4D accumulated doses, highlighting their impact on dose degradation in PBSPT, along with tumor movement and location.

Keywords: DIR, interplay effect, 4D dose accumulation.

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