ESTRO 2024 - Abstract Book

S4073

Physics - Inter-fraction motion management and offline adaptive radiotherapy

ESTRO 2024

Conclusion:

A substantial portion of the considered patients (35%) were found not to need re-planning during CK pancreas SBRT. An easy-to-calculate geometric parameter was validated which successfully identified those patients who are not at risk of exceeding dose tolerances and, on reverse, showed good performances in predicting patients who may benefit from plan adaptation.

Keywords: SBRT, pancreatic cancer, organ motion

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Digital Poster

Internal motion variations associated with respiratory phase changes during amplitude gating VMAT

Ryo Takahashi, Hidenobu Tachibana

National Cancer Center Hospital East, Section of Radiation Safety and Quality Assurance, Kashiwa, Japan

Purpose/Objective:

Currently respiratory-gated VMAT is common to reduce treatment volume in chest while keeping OARs sparing. Breathing is managed using amplitude or phase mode in respiratory-gated VMAT. Duty cycle is determined after gated window is set in amplitude mode. A constant amplitude of abdominal wall should be expected. However, we