Stereotactic radiosurgery in pediatric patients

Although stereotactic radiosurgery has been studied extensively in adults, the data demonstrating its efficacy in children is limited. Medical records were reviewed to identify the indications for and outcomes of patients treated with this modality. Linear accelerator-based radiosurgery was used to treat 11 recurrent brain tumors and one posterior fossa arteriovenous malformation over 3 years. The mean and median age of those treated was 10 and 8 years, respectively (range 1-20 years). Patients received 700 to 3,000 cGy delivered to the 50-90% isodose line in a single fraction. The mean and median follow-up was 15 and 17 months, respectively. Three of the four children with malignant disease died 6 to 9 months after treatment. One patient died of recurrence outside the treatment field. Another child died of complications related to radiation injury, and the third died of disease progression. All children with low-grade tumors remain alive without complications. Six of eight (75%) children exhibit substantial radiographic reductions in tumor size. The child with a vascular malformation has been followed for 26 months, without hemorrhage and with a radiographically proved decrease in size. Our series suggests that radiosurgery has limited usefulness in malignant disease. Therapeutic response is influenced by lesion size and/or location. Stereotactic radiosurgery appears to be effective in children with low-grade intracranial tumors or arteriovenous malformations. Further experience is required to establish the role and long term side effects of radiosurgery in pediatric patients.