40% of all cancers spread to the brain
Within the brain and spinal cord, there are nerve cells and also cells that support and protect the nerve cells. The supporting cells are called glial cells. A tumour of these cells is known as a glioma.
Ependymomas are a rare type of glioma. They develop from the ependymal cells which line the ventricles (fluid-filled spaces in the brain), and from the central canal of the spinal cord. They can be found in any part of the brain or spine, and in children are more common in the cerebellum.
Ependymomas may occasionally spread from the brain to the spinal cord in the cerebrospinal fluid (CSF). CSF is the fluid that surrounds and protects the brain and spinal cord.
People of all ages can develop ependymomas, including children. Tumours at the base of the brain, in an area called the posterior fossa, are more common in children. About 1 in 20 brain tumours (5%) is an ependymoma.