Definition

A type of glioma that begins in ependymal cells, which line the fluid-filled spaces in the brain and spinal cord and make cerebrospinal fluid. Ependymal tumors can form anywhere in the brain or spinal cord, but they usually form in the lower back part of the brain in children and in the spinal cord in adults. These tumors can occur at any age but are more common in young children. They can be low grade or high grade, determined by how abnormal the tumor cells look under a microscope and how quickly the tumor is likely to grow, spread, and come back after treatment. Most ependymal tumors are low grade, meaning they tend to grow and spread within the brain and spinal cord slowly. They rarely spread outside the brain and spinal cord. Childhood ependymal tumors often come back after treatment. Also called ependymoma.