Radiation Necrosis in Pediatric Proton Therapy for Central Nervous System Tumors: Current Evidence and Future...

Area of Science:

• Pediatric Oncology
• Radiation Oncology
• Neurology

Background:

• Radiation necrosis (RN) is a significant late complication following central nervous system irradiation in children.
• Proton beam therapy (PBT) is increasingly used to minimize normal-tissue exposure, necessitating a deeper understanding of RN.
• Factors influencing RN incidence in pediatric PBT include tumor characteristics, dose-volume parameters, follow-up duration, and linear energy transfer (LET).

Purpose of the Study:

• To review and synthesize current knowledge on risk factors, imaging evaluation, and management of radiation necrosis in pediatric patients treated with proton beam therapy.
• To highlight the unique considerations of PBT, such as elevated LET, in the context of RN.
• To emphasize the need for improved risk prediction and management strategies.

Main Methods:

• Review of existing literature on radiation necrosis following pediatric proton beam therapy.
• Analysis of reported incidence rates and associated risk factors.
• Evaluation of advanced magnetic resonance imaging (MRI) techniques for differentiating RN from tumor progression.
• Summary of current management strategies.

Main Results:

• RN incidence following pediatric PBT varies and is influenced by tumor specifics, dose-volume metrics, follow-up length, younger age, chemotherapy, and peritumoral white-matter dose.
• Elevated LET may present a unique risk profile compared to photon therapy.
• Advanced MRI techniques aid in distinguishing RN from progression, though accuracy is not perfect.
• Management options include corticosteroids, bevacizumab, hyperbaric oxygen, and surgery.

Conclusions:

• Understanding RN in pediatric PBT is crucial for optimizing treatment outcomes and preserving neurocognitive function.
• Prioritizing LET-aware planning, vigilant imaging surveillance, and prospective studies with radiogenomic profiling is essential for improved risk prediction and management.
• Further research is needed to refine strategies for managing RN and enhancing long-term quality-of-life in pediatric patients.