Comparison of Symptom Burden/Toxicity, Neurocognitive Change, and Functional Outcomes in Pediatric Brain Tumor Patients Treated with Proton vs. Photon Radiotherapy.

PROJECT SUMMARY Most children treated for cancer in the US will achieve long-term survival, and survivorship presents unique challenges for this growing population. Pediatric brain tumor survivors, in particular, are at risk for neurocognitive impairments, educational difficulties, social problems, and medical disabilities. Cranial radiation therapy is an

essential lifesaving treatment but is associated with cognitive decline. Proton beam radiation therapy (PBRT) is one of the most promising recent advances in pediatric brain tumor treatment. The proposed medical advantage of PBRT lies in the precision of radiation delivery with proton beams, depositing maximum dose to clinical targets

while minimizing radiation to surrounding tissues. By reducing dose to healthy brain tissue, PBRT may spare cognitive functioning and reduce symptom burden better than conventional photon or x-ray irradiation (XRT) leading to greater functional independence in survivorship. The proposed Diversity Supplement Study leverages data collected on the Parent R01 at on-radiotherapy

(RT) time points to examine acute experiences of symptom burden and toxicity in this multi-national study. Comparisons of prospectively assessed acute outcomes between PBRT and XRT pediatric brain tumor groups have not been published to date, making this a novel study that will inform our understanding of RT modality

differences. The following aims, which map onto Aim 1 of the Parent R01, are proposed: (1a) to compare acute symptom burden/toxicity by RT type (PBRT vs. XRT) in pediatric brain tumor patients and (1b) to examine risk factors of symptom burden/toxicity during RT. The Diversity Supplement Study is within the scope of the Parent

R01 while also providing a clinically meaningful expansion of this line of research.