2474 - Impact of Cranial Proton Therapy on White Matter Development and Quality-of-Life in Pediatric Patients
Presenter(s)
S. H. Seo1,2, S. K. Yoo3, H. Park2, D. H. Lim4, N. Kim4, and J. S. Kim3,5; 1Department of Clinical Medicine, Sungkyunkwan University School of Medicine, Suwon, Korea, Republic of (South), 2Oncosoft Inc., Seoul, Korea, Republic of (South), 3Department of Radiation Oncology, Yonsei Cancer Center, Heavy Ion Therapy Research Institute, Yonsei University College of Medicine, Seoul, Korea, Republic of (South), 4Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, Republic of (South), 5Oncosoft, Seoul, Korea, Republic of (South)
Purpose/Objective(s): Proton therapy (PT) may influence quality-of-life (QOL) by affecting white matter (WM), which is critical for cognitive function but vulnerable to radiation-induced damage. However, the relationship between WM changes and QOL trajectories remains unclear. This interim analysis of a prospective cohort study examines the association between longitudinal QOL changes and WM alterations in pediatric patients after PT.
Materials/Methods: This prospective cohort study included pediatric patients who underwent PT since April 2018. QOL was assessed using the PedsQLTM 4.0 Generic Core, reported by both patients and parents at baseline, every 3-6 months, and annually. Total QOL scores encompassed physical and psychosocial domains, with poor QOL defined as <70 (patients) or <65 (parents). Patients were categorized into three groups: improved (=2 instances of good QOL after a poor baseline), deteriorated (=2 instances of poor QOL after a good baseline), and sustained QOL (consistently poor or good). WM segmentation was performed using an in-house auto-segmentation model that achieved a Dice similarity coefficient of 0.81. This analysis focused on 3-year follow-up data, examining longitudinal QOL trajectories and WM changes using a linear mixed model.
Results: From April 2018 to April 2023, 90 patients were enrolled (median age: 10 years; interquartile range, 5-14), including 12 patients under 3 years. Germ cell tumors were the most common diagnosis (44.4%). Half of patients received whole brain or cranio-spinal irradiation, with a median total dose of 36 GyE. Both patients and parents reported significant improvements in physical and psychosocial QOL over time (p<0.05). At baseline, 34/90 patients and 40/90 parents reported poor QOL. During follow-up, 14/34 patients and 20/40 parents exhibited sustained poor QOL, which was associated with smaller WM volume increases or slight decreases compared to those with improved QOL (p=0.023, p=0.001). Patients with improved physical/psychosocial QOL showed gradual WM volume increases (p<0.05). No significant difference in WM change was observed between patients with sustained good QOL and those with deteriorated QOL. Additionally, PT dose = 30GyE was associated with a significantly smaller WM volume increase (p=0.008), while PT field (partial vs. whole-brain) had no significant impact (p=0.158).
Conclusion: QOL improved over time after PT, but some patients experienced persistent deficits. WM volume changes were associated with QOL trajectories, with smaller increases in those with sustained poor QOL. Higher radiation dose was related to reduced WM volume increases, emphasizing the need for dose optimization to mitigate long-term effects.