P05.05 * radiosurgery in the management of pediatric brain tumors

BACKGROUND: Brain tumors are the most frequent solid tumors in the pediatric age. Their treatment is usually neurosurgical, followed by chemo and/or radiation therapy. Radiosurgery allows the administration of a high radiation dose to a well defined target in 1 to 5 fractions, with minimal dose to the surrounding tissues. This fact would make it especially indicated for certain situations of children with these tumors. There are scarce publications, all retrospective studies, with specific attention to this treatment in the pediatric population. METHOD: The aim of this study has been to review our experience of the pediatric patients with brain tumors treated at our Radiosurgery Unit from 1993 to 2013. Data were obtained retrospectively from a prospectively maintained database. We have reviewed 94 patients with central nervous system tumors below the age of 16 (range 8m- 15y, median 12y) with a complete follow-up in 71.7%, during a mean of 56.2 months. RESULTS: The treated tumors have a miscellanea of different diagnosis, the most frequent being 26 low grade gliomas (LGG), 19 craniopharyngiomas (CFG), 8 ependymomas (EP), 6 medulloblastomas-PNET (M-PNET) and 6 patients with tumors related to neurofibromatosis. Among the 21 followed LGG, control was achieved in 90.5%. In CFG, and as part of the multimodal treatment of these tumors, visual, hormonal and solid tumor stability was obtained in 14 out of 18, although in 3 patients stereotactic evacuation of the cystic component was necessary. As EP and M-PNET had already received radiotherapy, radiosurgery was a good option as a boost or salvage treatment, with good local control, but with outfield relapses, that could be further treated when necessary. CONCLUSION: This advanced technique of focalized radiation therapy, with high precision and accuracy, provides dosimeric characteristics especially relevant in children that are more susceptible to irradiation. It produces promising results in selected patients.