Ependymoma is the third most common brain tumor in children. Accordingly, the first age peak can already be observed in childhood (at the age of five). In adults, the peak age is in the third decade of life.
In general, ependymomas account for 10 percent of all primary tumors of the central nervous system and are therefore very rare.
Depending on their localization (= site of occurrence), doctors distinguish between
- intracranial (inside the skull) and
- intraspinal (in the spinal column)
tumors.
Intraspinal ependymomas can occur in the entire central canal of the spinal cord. However, they primarily grow at the lower end of the spinal cord - at the so-called conus medularis and filum terminale.
In the case of intracranial ependymomas, the tumour disease is predominantly localized in the IV ventricle (4th cerebral cavity).
Furthermore, ependymomas can be divided into four subtypes based on their histologic differences:
- Subependymomas: Often bulbous protrusion into the cerebral ventricle
- Myxopapillary ependymomas: Almost exclusively at the lower end of the spinal cord and in the section of the spinal canal in which the nerve roots are arranged like a horse's tail (Latin "cauda equina"). It mainly affects adults.
- Ependymomas: In the spinal cord or in the inner ventricles of the brain
- Anaplastic ependymomas: Particularly in children
According to the WHO, these four subgroups are in turn differentiated into three degrees of malignancy. Malignancy describes how aggressively the cancer spreads to the surrounding tissue, organs and the entire organism.
WHO grade I and WHO grade II ependymomas are considered slow-growing, well-limited and benign (= benign ependymomas).
Subependymomas and myxopapillary ependymomas are classified as WHO grade I, ependymomas as WHO grade II.
Anaplastic ependymomas(WHO grade III) grow rapidly and are considered malignant (= malignant ependymomas). They also tend to grow into the adjacent tissue structures (infiltration).
The symptoms associated with an ependymoma depend on
- the exact location of the tumor and
- which nerve endings in the spinal canal are disturbed or compressed by the mass.
In some cases, infants and small children may experience
- impaired development,
- tendency to fall and
- changes in behavior.
In adults, the first symptoms usually appear in early adulthood. In over 60 percent of cases, those affected complain of local pain. Around half of those affected also show sensory disturbances (paresis) at the time of diagnosis.
If the tumor is located in the area of the cervical spine, spinal ataxia can occur. This is a disorder of normal movement sequences and leads to uncontrolled and uncoordinated movements.
In rare cases (2 percent), a bladder-mast bowel disorder also occurs.
If the cancer is located in the ventricular system of the brain, the flow of cerebrospinal fluid is obstructed by the mass. In this case, the cerebrospinal fluid can no longer flow freely. This leads to various impairments (including visual disturbances).
Cerebrospinal fluid circulates in the spaces between the brain and the spinal cord © Martin | AdobeStock
In addition, an increase in intracranial pressure often leads to the formation of hydrocephalus ("hydrocephalus"). Signs of increased intracranial pressure include
headaches.
You should consult your family doctor immediately if you notice the above symptoms. This applies in particular to children with persistent headaches.
If a tumour of the central nervous system is suspected, the family doctor or paediatrician will refer you to a specialized center. There, an interdisciplinary team will carry out further examinations.
The examinations required to diagnose an ependymoma include magnetic resonance imaging(MRI) and myelo-computed tomography.
Ependymomas can develop so-called "drip metastases". Doctors refer to certain tumor metastases as drip metastases. They develop when detached cancer cells migrate within body cavities - here in the cerebrospinal fluid pathway - by gravity alone. They then settle in other parts of the body or organs.
This is why the specialist also checks the entire cerebrospinal fluid space using the imaging procedure. A cerebrospinal fluid examination can also be used to check whether there are tumor cells in the cerebrospinal fluid.
Surgical treatment of ependymomas
Ependymomas are usually encapsulated by the adjacent spinal cord. The oncologist can therefore easily remove the tumor as part of a microsurgical extirpation. Extirpation is the surgical removal of parts of the organ.
Complete removal of the tumor is successful in 9 out of 10 patients.
How much the surgeon has to remove depends on
- the extent,
- the localization and
- the degree of malignancy
of the tumor.
Higher-grade tumors are usually less well encapsulated. The surgeon is therefore not always able to remove them completely. In this case, a subsequent extirpation may be indicated.
Radiotherapy and chemotherapy not always necessary
In some cases, oncologists also recommend radiotherapy to kill the remaining tumor cells in the body. This is necessary if
- incomplete removal of the tumor,
- grade III tumors and
- recurrences (recurrence of the cancer).
Oncologists also usually carry out radiotherapy of the neuroaxis in the event of metastasis in the cerebrospinal fluid.
Chemotherapy is generally not necessary. However, it can be used for high-risk patients or children as part of studies. The doctor may also treat very advanced tumors with chemotherapeutic agents.
Accompanying drug treatment
Medication helps to alleviate symptoms caused by the increased intracranial pressure, such as headaches and nausea. Cortisone preparations, for example, reduce the intracranial pressure and thus also reduce the accompanying symptoms.
Benign grade I and IIependymomas generally do not require concomitant treatment. However, they have a recurrence rate of five percent after five and ten years. This means that there is a five percent probability that an ependymoma will develop again after a few years.
The doctor therefore carries out follow-up examinations at regular intervals (MRI with contrast medium). The first check-up takes place six weeks after the end of treatment.
After that, the doctor checks the success of the treatment every six months for the first two years and then every 12 months.
In rare cases,malignant ependymomas (grade III) tend to metastasize systemically. The oncologist therefore monitors them more closely and carries out check-ups every three months.
Overall, the prognosis is comparatively favorable, especially if the tumor tissue is completely removed. The 5-year survival rate is over 50 percent.
The likelihood of sequelae also depends on the deficits present before the operation. Permanent neurological deficits can occur in around a fifth of those affected. These are caused by the tumor itself or the therapy (especially radiation).
