[Hypofractionated stereotactic irradiation for optic nerve glioma]

Area of Science:

• Oncology
• Radiation Oncology
• Pediatric Neuro-oncology

Background:

• Optic nerve glioma is a rare tumor primarily affecting children, often associated with neurofibromatosis type I.
• Tumors can cause decreased visual function and exophthalmos, necessitating individualized treatment strategies.
• Radiotherapy is a treatment option, with hypofractionated irradiation being explored as a potential advancement.

Purpose of the Study:

• To evaluate the safety and efficacy of hypofractionated radiotherapy for optic nerve glioma.

Main Methods:

• Sixteen patients (14 children, 2 adults) with optic nerve gliomas received hypofractionated stereotactic irradiation (CyberKnife).
• Treatment involved 5 fractions to a total dose of 27.5 Gy (5.5 Gy per fraction).
• Patient data included age, tumor volume, and pre- and post-treatment visual function and proptosis measurements.

Main Results:

• Tumor growth control was achieved in 100% of patients.
• Partial remission was observed in 32% of patients, with no deterioration in visual function.
• Improvements in visual acuity (19%) and visual field enlargement (67%) were noted, alongside a decrease in proptosis (60%).

Conclusions:

• Hypofractionated stereotactic radiotherapy is a safe and effective treatment for optic nerve gliomas.
• The technique demonstrates significant potential for tumor control, visual function preservation/improvement, and reduction of proptosis.