ESTRO 2025 - Abstract Book

S1394

Clinical - Lung

ESTRO 2025

Conclusion: Dose spill outside the PTV may be essential for local control in lung SABR with a 30% background dose sufficient to control MD. It may therefore be beneficial to define a secondary, larger CTV (with a margin >1 cm) for lung SABR, prescribed at a lower dose, to improve local control. Such a prescription would hardly affect the dose in-plane as it coincides with existing dose spill but adds a low dose bath to control MD out-of-plane.

Keywords: SABR, microscopic disease, loco-regional control

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