ESTRO 2025 - Abstract Book

S2762

Physics - Dose prediction, optimisation and applications of photon and electron planning

ESTRO 2025

sparing with partial arcs could achieve to a mean carotid dose of 12.1Gy. This technique would increase doses to the spinal cord max dose by 26% to 28.1Gy which is still below OAR tolerance. Minimal dosimetric impact on constrictor muscles. Laterality of the larynx primary has impact on carotid doses due to PTV 55Gy isodose level. Therefore, carotid artery sparing can be delivered safely. Optimal arc selection The most optimal VMAT technique for early glottic cancers is partial arc arrangements. Full arcs are inferior to partial arcs with carotid sparing optimisation resulted in 53% increase of mean dose to combined bilateral carotid mean doses.

Conclusion: Carotid artery sparing is feasible in early stage glottic cancers achieving safe and acceptable dosimetric impact on major adjacent OARs of spinal cord and constrictor muscle. VMAT radiotherapy with partial arcs arrangements offer the best dosimetry for carotid sparing in early glottic cancers. Future studies should explore the optimal constraints of carotid artery doses in head and neck cancer radiotherapy planning.

Keywords: carotid artery, dose sparing, glottic cancers

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