Radiotherapeutic management of intracranial ependymoma.

Ependymomas comprise about 10% of all pediatric brain tumors. The most consistent prognostic factor for cure has been the extent of surgical resection. Radiation therapy is considered the standard adjuvant treatment, although there has been no randomized trial comparing surgery alone to surgery and postoperative radiotherapy. Craniospinal irradiation has been used in the past to treat these tumors; however, current data indicate that the most common pattern of failure is an isolated local relapse. Furthermore, prophylactic spinal irradiation has not been shown to prevent spinal dissemination. For this reason, most radiation oncologists currently employ localized radiotherapy fields. Available data indicate that doses greater than 45-50 Gy are needed and associated with better local control. Preliminary data using hyperfractionated radiotherapy doses of greater than 65 Gy indicate an improvement in progression-free survival for subtotally respected ependymoma. Chemotherapy can be used to delay institution of radiotherapy in children less than 3 years of age. The role of hemotherapy in older children needs to be further defined.