ESTRO 2024 - Abstract Book

S4159

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

ESTRO 2024

Results:

The size of the PTV was reduced by an average of 37% for the tracking-based treatment plans compared to the ITV based plans. The mean lung dose was reduced by 9% on average when using the tracking-based treatment plans.

The motion induced in the tumours had standard deviations of 1.9 mm, 5.9 mm, and 4.2 mm in the left-right, superior inferior, and anterior-posterior directions respectively. The relative motion between targets had standard deviations of 3.3 mm, 4.3 mm, and 4.0 mm in the left-right, superior-inferior, and anterior-posterior directions respectively.

Error to the GTVs was lower when using the multi-target tracking-based approach with average gamma-failure rates of 1.2% ± 1.2% compared to 9.3% ± 8.4% when the ITV-based approach was used.