Brief overview
- Causes: The reasons for the development of an ependymoma are unclear. Possible risk factors are certain diseases such as neurofibromatosis type 2, which are based on a disorder in the genetic material. Exposure to radiation, for example during treatment for other cancers, is also suspected to be a trigger.
- Symptoms: Depending on the severity, possible symptoms include headaches (especially in the morning and at night), nausea and vomiting, an accelerated increase in head circumference in small children and neurological disorders.
- Diagnosis: Medical history, physical examination, magnetic resonance imaging and computer tomography (MRI, CT), tissue, blood and cerebrospinal fluid tests
- Treatment: As a rule, the doctor operates on the tumor, removing it partially or completely depending on its severity. In addition, radiotherapy and, less frequently, chemotherapy may be considered.
- Prognosis: If the tumor is completely removed, the prognosis is quite good. The more malignant the tumor is, the more difficult it is to treat and the lower the chances of recovery.
What is an ependymoma?
However, adults also sometimes develop this tumor, albeit much less frequently. Ependymomas account for only two percent of all brain tumors in adults.
An ependymoma forms from ependymal cells, which belong to the supporting cells (glial cells) of the central nervous system. These line the inner wall of the individual cerebral ventricles and the spinal canal, in which the cerebrospinal fluid is located. The ventricles are connected to each other and to the spinal canal via so-called cerebrospinal fluid pathways.
In principle, it is possible for the tumor to form at any point on these inner walls. In children and adolescents, it most frequently develops in the fourth ventricle of the posterior fossa. From there, the ependymoma often spreads towards the cerebellum, brain stem or upper cervical cord. In some cases, it also develops in the cerebrum. An ependymoma in the spinal canal occurs more frequently in adults and is not as common overall.
Metastasis formation
WHO classification
The World Health Organization (WHO) divides ependymoma, like all other brain tumors, into different degrees of severity:
- WHO grade 1: Subependymoma and myxopapillary ependymoma
- WHO grade 2: Ependymoma
- WHO grade 3: Anaplastic ependymoma
The subependymoma is a benign tumor. It bulges into the inner ventricles of the brain and is often only discovered by chance.
Myxopapillary ependymoma is also benign. It grows exclusively in the lowest part of the spinal canal and occurs in adults.
An anaplastic ependymoma is mainly found in children. It grows very quickly and has a less good prognosis as it grows into the adjacent tissue – in contrast to the first and second degree tumor types, which are usually well demarcated from healthy brain tissue.
What are the signs of an ependymoma?
Due to its proximity to the cerebrospinal fluid pathways, it is often the case that an ependymoma obstructs these pathways. As a result, the cerebrospinal fluid may no longer drain properly and the pressure on the brain increases. This often results in severe headaches that can hardly be alleviated by medication.
In younger children in particular, an ependymoma often increases the circumference of the head (macrocephalus). In some patients, the tumor becomes noticeable through a seizure. In addition, there are problems with walking, seeing, sleeping and concentrating. An ependymoma sometimes causes paralysis.
Read more about the symptoms of brain tumors in the article Brain tumor – symptoms.
What causes an ependymoma?
Why an ependymoma develops has not yet been conclusively researched. It is also still unclear whether this form of brain tumor is hereditary.
People who have undergone radiotherapy as part of cancer treatment have an increased risk of developing the disease. Children sometimes receive radiotherapy for leukemia (white blood cancer) or the malignant eye tumor retinoblastoma and are more likely to develop a brain tumor even years later.
Ependymomas in the spinal cord occur more frequently in connection with the hereditary disease neurofibromatosis type 2.
How is an ependymoma diagnosed?
Affected persons with symptoms often first consult their family doctor or pediatrician. They ask about the exact symptoms and their course, any previous and underlying illnesses and the general state of health (medical history).
An ependymoma is best visualized in a magnetic resonance imaging (MRI) scan. The doctor usually injects the patient with a contrast agent into a vein before the examination. The tumor absorbs this contrast agent and lights up irregularly in the MRI image. This allows its location, size and spread to be determined very well.
The cerebrospinal fluid examination (cerebrospinal fluid diagnostics) supplements a detailed diagnosis of ependymoma. Here it is possible to detect individual tumor cells. In addition, the doctor usually takes a tissue sample from the tumor and examines it under the microscope. This is necessary in order to tailor the subsequent therapy optimally to the patient.
Treatment of an ependymoma
The first therapeutic step for an ependymoma is the complete surgical removal of the tumor, which is often possible nowadays for tumors in the spinal cord. Tumors in the brain, on the other hand, cannot usually be completely removed.
Other medications are used to treat accompanying symptoms such as headaches or nausea. Ependymoma can also be treated with cortisone preparations. They reduce swelling in the brain tissue and thus reduce existing intracranial pressure.
Further information on examinations and treatment can be found in the article Brain tumor.
What is the course of the disease with an ependymoma?
The course of the disease and the prognosis for an ependymoma depend on various factors and are therefore very different in each individual case. Decisive factors include where the tumor is located, whether it can be completely removed surgically and whether it has already spread.
If the tumor region is completely removed with post-irradiation, 60 to 75 percent of patients are still alive five years later and 50 to 60 percent ten years later. The prerequisite for this is that the disease does not progress. If it is not possible to remove the ependymoma completely and those affected have received follow-up radiotherapy, the survival rate drops to 30 to 40 percent after ten years.
