Combining Clinical and Dosimetric Features in a PBS Proton Therapy Cohort to Develop a NTCP Model for Radiation-Induced Optic Neuropathy

Purpose Radiation-induced optic neuropathy (RION) is a rare, yet severe complication following radiation therapy for brain, head and neck, or skull-base tumors. Although several risk factors, such as age, metabolic syndrome, delivered dose, have been identified, we aimed at expanding the understanding of mechanisms interplay regarding dosimetry patient variables leading to onset RION with focus on proton therapy. Methods Materials In this retrospective study, investigated proton-specific factors by comparing common phenomenological normal tissue probability models multivariate analysis that includes clinical features cohort patients neck cancer treated pencil beam scanning. Results predictive power Lyman-Kutcher-Burman Poisson was limited data set, addition tumor involvement, hypertension, sex remarkably increased model performance. Conclusions Based our assessment, maximum dose in optical apparatus confirmed most intuitive factor. However, above certain threshold, characteristics are deciding RION. We observed tendency toward volume effect that, if confirmed, would imply benefit high precision techniques treatment