Outcomes Following Proton Therapy for Pediatric Low-Grade Glioma Indelicato, Daniel J. et al. International Journal of Radiation Oncology • Biology • Physics , Volume 104 , Issue 1 , 149 – 156.
Low-grade gliomas (LGGs) are the most common brain tumors in children, with approximately 800 cases diagnosed each year in the United States. Management of these tumors depends on several elements, including host factors (eg, patient age and comorbidities) and disease characteristics (eg, tumor location and histologic subtype). With a long-term survival rate that exceeds 90%, therapy selection involves careful consideration of minimizing late toxicity from surgery, chemotherapy, and irradiation. Treatment side effects can be permanent or life threatening and include neurocognitive impairment, neurologic deficits, neurovascular compromise, neuroendocrine deficiency, and second malignancies.
Surgery, radiation therapy, and chemotherapy may be used as solitary therapies or in combination, offering different therapeutic ratios depending on the setting. As a result, establishing the ideal treatment choice and sequencing has historically been an area of controversy, presenting challenges that are further complicated by the emergence of molecular targets.
Several studies have attempted to mitigate the impact of late radiation toxicity through selective radiation avoidance, systematic reduction in the size of target volumes, and the use of advanced radiation techniques. Of these radiation techniques, proton therapy is particularly promising because it allows for reductions in the low and intermediate radiation dose to normal tissue outside of the target volume. Accordingly, LGGs in children are considered a “Group 1” indication for proton therapy according to the United States American Society for Radiation Oncology Model Policy, and they have become the third most common pediatric brain tumor type treated with proton therapy worldwide.
Compared with modern photon series, proton therapy reduces the radiation dose to developing brain tissue, diminishing acute toxicities without compromising disease control.