Ependymoma
Encyclopedia
Ependymoma is a tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...

 that arises from the ependyma
Ependyma
Ependyma is the thin epithelial membrane lining the ventricular system of the brain and the spinal cord. Ependyma is one of the four types of neuroglia in the central nervous system. It is involved in the production of cerebrospinal fluid ....

, a tissue of the central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...

. Usually, in pediatric cases
Pediatric Ependymoma
Pediatric ependymomas are similar in nature to the adult form of ependymoma in that they are thought to arise from radial glial cells lining the ventricular system. However, they differ from adult ependymomas in which genes and chromosomes are most often affected, the region of the brain they are...

 the location is intracranial, while in adults it is spinal
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...

. The common location of intracranial ependymoma is the fourth ventricle
Fourth ventricle
The fourth ventricle is one of the four connected fluid-filled cavities within the human brain. These cavities, known collectively as the ventricular system, consist of the left and right lateral ventricles, the third ventricle, and the fourth ventricle...

. Rarely, ependymoma can occur in the pelvic cavity
Pelvic cavity
-External links:* * *...

.

Syringomyelia
Syringomyelia
Syringomyelia is a generic term referring to a disorder in which a cyst or cavity forms within the spinal cord. This cyst, called a syrinx, can expand and elongate over time, destroying the spinal cord. The damage may result in pain, paralysis, weakness, and stiffness in the back, shoulders, and...

 can be caused by an ependymoma.
Ependymomas are also seen with neurofibromatosis type II
Neurofibromatosis type II
Neurofibromatosis Type II is an inherited disease. The main manifestation of the disease is the development of symmetric, non-malignant brain tumours in the region of the cranial nerve VIII, which is the auditory-vestibular nerve that transmits sensory information from the inner ear to the...

.

Symptoms

  • severe headache
  • visual loss
  • vomiting
  • bilateral Babinski sign
  • drowsiness (after several hours of the above symptoms)


Morphology

Ependymomas are composed of cells with regular, round to oval nuclei. There is a variably dense fibrillary background. Tumor cells may form gland-like round or elongated structures that resemble the embryologic ependymal canal, with long, delicate processes extending into the lumen; more frequently present are perivascular pseudorosettes in which tumor cells are arranged around vessels with an intervening zone consisting of thin ependymal processes directed toward the wall of the vessel.

It has been suggested that ependymomas are derived from radial glia.

Ependymoma tumors

Ependymomas make up about 5% of adult intracranial glioma
Glioma
A glioma is a type of tumor that starts in the brain or spine. It is called a glioma because it arises from glial cells. The most common site of gliomas is the brain.-By type of cell:...

s and up to 10% of childhood tumors of the central nervous system (CNS). Their occurrence seems to peak at age 5 years and then again at age 35. They develop from cells that line both the hollow cavities of the brain and the canal containing the spinal cord, but they usually arise from the floor of the fourth ventricle, situated in the lower back portion of the brain, where they may produce headache, nausea and vomiting by obstructing the flow of cerebrospinal fluid. This obstruction may also cause hydrocephalus
Hydrocephalus
Hydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...

. Other symptoms can include (but are not limited to): loss of appetite, difficulty sleeping, temporary inability to distinguish colors, uncontrollable twitching, seeing vertical or horizontal lines when in bright light, and temporary memory loss. It should be remembered that these symptoms also are prevalent in many other illnesses not associated with ependymoma.

About 85% of ependymomas are benign myxopapillary ependymoma (MPE). MPE is a localized and slowly growing, low-grade tumor. Although some ependymomas are of a more anaplastic and malignant type, most of them are not anaplastic. For this reason, well-differentiated ependymomas are usually treated with radiation therapy only. For other ependymomas, total surgical removal is the preferred treatment and those that cannot be totally removed also require radiation therapy. The malignant (anaplastic) varieties of this tumor, malignant ependymoma and the ependymoblastoma, are treated similarly to medulloblastoma
Medulloblastoma
Medulloblastoma is a highly malignant primary brain tumor that originates in the cerebellum or posterior fossa.Previously, medulloblastomas were thought to represent a subset of primitive neuroectodermal tumor of the posterior fossa...

 but the prognosis is much less favorable. Malignant ependymomas may be treated with a combination of radiation therapy and chemotherapy. Ependymoblastomas, which occur in infants and children younger than 5 years of age, may spread through the cerebrospinal fluid and usually require radiation therapy. The subependymoma, a variant of the ependymoma, is apt to arise in the fourth ventricle but may occur in the septum pellucidum
Septum pellucidum
The septum pellucidum , and not to be confused with the medial septum, is a thin, triangular, vertical membrane separating the anterior horns of the left and right lateral ventricles of the brain...

 and the cervical spinal cord. It usually affects people over 40 years of age and more often affects men than women.

Extraspinal ependymoma (EEP), also known as extradural ependymoma, may be an unusual form of teratoma
Teratoma
A teratoma is an encapsulated tumor with tissue or organ components resembling normal derivatives of all three germ layers. There are rare occasions when not all three germ layers are identifiable...

 or may be confused with a sacrococcygeal teratoma
Sacrococcygeal teratoma
Sacrococcygeal teratoma is a teratoma located at the base of the coccyx . It is thought to be a derivative of the primitive streak.-Natural history:...

.

External links


Images and technical information


Treatment Information

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