Ependymoma Health Article

Definition

An ependymoma is a rare type of primary brain tumor that develops from the ependymal cells lining the ventricles of the brain and the central canal of the spinal cord. Ependymomas can be found anywhere in the brain or spine but are usually located in the main part of the brain, the cerebrum, and may spread from the brain to the spinal cord via the cerebrospinal fluid (CSF).

Description

Most brain tumors are named after the cells in which they are found, thus the name ependymoma for a tumor of ependymal cells. Ependymomas are classified as either supratentorial (located in the top part of the head) or infratentorial (located in the back of the head). In children, most ependymomas are of the infratentorial type and occur in or close to the fourth ventricle of the brain. Ependymomas may block the flow of cerebrospinal fluid out of the ventricles causing them to enlarge—a condition called hydrocephalus. Unlike other types of brain tumors, ependymomas as a rule do not spread into healthy brain tissue or outside the brain or spinal cord. As a result, it is often the case that they can be removed and cured by surgery, especially spinal cord ependymomas.

Demographics

Ependymomas are infrequent tumors, representing 2% to 8% of all brain tumors. However, ependymomas are the third most common brain tumor in childhood (5% to 10%) and are diagnosed in about 75 to 150 children each year in the United States. More than 50% of all ependymomas are diagnosed during childhood. In adults, ependymomas of the spine account for over half of all spinal tumors. The occurrence of ependymomas is equal among all races.

Causes and symptoms

As is the case for most brain tumors, the cause of ependymoma is unknown. Ependymal cells usually grow in an orderly and controlled way, but if for some reason this process is disrupted, the cells continue to divide and form a tumor. Research is being carried out to identify possible contributing factors. Little is known, but researchers have begun to make progress in the areas of genetic, hereditary, and environmental causes.

The first symptoms of any type of brain tumor are usually due to increased pressure within the skull. This may be the result of a blockage in the ventricles of the brain causing a buildup of CSF or may be induced by swelling around the tumor itself. The increased pressure can cause headaches, vomiting and visual problems. Symptoms specific to ependymomas include swelling of the optic nerve, rapid and jerky eye movements, neck pain and irritability. Seizures, fits and personality changes are also general symptoms associated with a brain tumor. About 25% of children with ependymomas have seizures. Other ependymoma symptoms depend on which area of the brain is affected.

• If located in the frontal lobe of the brain, ependymomas may cause mood swings, personality changes, and paralysis on one side of the body.
• If occurring on the temporal lobe of the brain, coordination, speech, and memory problems may result.
• If located on the parietal lobe of the brain, the condition may affect writing and related tasks.
• If located in the cerebellum, ependymomas may cause unsteady gait and problems with coordination and balance.

Diagnosis

To plan treatment, doctors need to find out as much as they can about the type, location, and size of the ependymoma. A number of diagnostic tests and examinations are scheduled. The first test is a neurological examination to evaluate any effect the tumor may have had on the nervous system. Every patient with ependymoma is usually subjected to diagnostic imaging of the spinal cord and brain. The most sensitive method available for evaluating spinal cord metastasis is spinal magnetic resonance imaging (MRI) performed with gadolinium, a contrast agent injected into the patient before the procedure. Other imaging studies—such as a CT scan—may also be performed to find the exact location and size of the ependymoma. To confirm the diagnosis, a biopsy will be perfomed and an ependymoma specimen will be examined under a microscope. Ependymomas sometimes spread from their original location through the CSF. An additional test called a myelogram may be done to check for this condition and to see if the tumor has spread to the spinal cord.

Treatment team

The primary physician will recommend one or more types of treatment based on the ependymoma diagnosis (size, location, type) and on the patient's medical history, age, and overall health. As a rule, the treatment team includes a neurosurgeon, a neurologist, a radiation oncologist and a medical oncologist.