Stereotactic radiotherapy and radiosurgery in pediatric patients: analysis of indications and outcome.

INTRODUCTION: We describe indications, outcomes, and risk profiles of fractionated stereotactic radiotherapy (SRT) and single fraction "radiosurgery" (SRS) in pediatric patients compared to the adult population and evaluate the causal role of SRS and SRT in inducing new neurological complications.
MATERIALS AND METHODS: Six children with AVMs and 12 children with neoplastic diseases were prospectively followed for >2 years after SRT/S. The survival, control of pathology, and specified neurological complications were analyzed. In tumor patients, the median overall survival time was 45 months (range 5-103) and the median progression free survival time was 35 months (range 5-98).
RESULTS: Control or regression of the tumor was obtained in 83% of patients with neoplastic disease. Three patients with malignant tumors died from disease progression. In AVMs the median time follow up was 52 months (range 27-100). All AVMs were obliterated. New neurological deficits occurred in 67%. SRT/S was considered the direct cause in 25%. All the neurological deficiencies related to SRT/S were focal and related to the irradiated areas. In tumor patients, midline lesions, malignant diagnosis, and additional treatment with surgery, chemotherapy, and craniospinal irradiation seemed to increase the risk of new deficits after SRT/S. In AVM patients, a high Spetzler-Martin grade seemed to carry a higher complication risk.
CONCLUSION: The risk of uncontrolled tumor disease or the risk of hemorrhage of non-obliterated AVM must be balanced against the overall risks and benefits of SRT/S. Following SRT/S, the risk of worsening pre-existing deficits is relatively high. The risk of inducing new long-term deficits is relatively low.