Fractionated stereotactic radiotherapy of optic pathway gliomas: tolerance and long-term outcome

PURPOSE: To evaluate the effectiveness and toxicity of fractionated stereotactically guided radiotherapy (FSRT) in the management of optic glioma. METHODS AND MATERIALS: Fifteen patients with optic pathway gliomas were treated with FSRT at our institution between 1990 and 2003. A median target dose of 52.2 Gy (range, 45.2-57.6 Gy) was applied using a median fractionation of 5 fractions of 1.8 Gy weekly using a linear accelerator. RESULTS: The median follow-up time was 97 months (range, 8-151 months). Of the 15 patients, 1 died of tumor progression during the follow-up period. The progression-free survival rate at 3 and 5 years was 92% and 72%, respectively. The median overall survival after FSRT was 90 months (range, 8-151 months). The 5-year survival rate after FSRT was 90%. We did not observe secondary malignancies. CONCLUSION: Fractionated stereotactic radiotherapy was safe and well tolerated in all patients. The good tumor control and the potential of sparing normal brain tissue, especially the pituitary gland in lesions involving the optic chiasm, permit effective treatment of patients with optic nerve gliomas. Longer follow-up is needed to assess the incidence of late effects fully.