Optimization of radiation therapy in the treatment of recurrent anaplastic ependymomas in children and adolescents

Primary brain tumors, which include ependymomas (E.), are the most common group of solid tumors in children and adolescents. E. account for 9% of all brain and spinal cord tumors in children and adolescents and are the 3rd most common among CNS tumors. E. arise from ependymal cells that line the ventricles of the brain. They can be located supratentorially, infratentorially, and in the spinal cord. In children, the most frequent localization of E. is in the brain (65-75% infratentorially, 20-25% supratentorially), less frequently in the spinal cord: 10-15%. There are not enough studies in the literature to evaluate the results of overall and recurrence-free survival after extended radiation therapy of E., the frequency of late radiation reactions; there are no generally accepted approaches to the treatment of E. recurrences and few data on complications after retreatment. Our work shows higher efficacy of conformal radiation therapy (RT) compared to conventional irradiation for anaplastic ependymomas of the brain in children and adolescents, which is consistent with the data of studies of treatment of other tumors (prostate cancer, malignant liver tumors, cervical cancer, lung cancer, pharyngeal cancer). We see further progress in this area in the improvement of conformal RT.