An ependymoma is a

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

that arises from the

ependyma The ependyma is the thin neuroepithelial ( simple columnar ciliated epithelium) lining of the ventricular system of the brain and the central canal of the spinal cord. The ependyma is one of the four types of neuroglia in the central nervous syst ...

, a tissue of the

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...

. Usually, in pediatric cases the location is

intracranial The cranial cavity, also known as intracranial space, is the space within the skull that accommodates the brain. The skull minus the mandible is called the ''cranium''. The cavity is formed by eight cranial bones known as the neurocranium that in ...

, while in adults it is spinal. The common location of intracranial ependymomas is the

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 ve ...

. Rarely, ependymomas can occur in the

pelvic cavity The pelvic cavity is a body cavity that is bounded by the bones of the pelvis. Its oblique roof is the pelvic inlet (the superior opening of the pelvis). Its lower boundary is the pelvic floor. The pelvic cavity primarily contains the reproduc ...

Syringomyelia Syringomyelia is a generic term referring to a disorder in which a cyst or cavity forms within the spinal cord. Often, syringomyelia is used as a generic term before an etiology is determined. This cyst, called a syrinx, can expand and elongate o ...

can be caused by an ependymoma. Ependymomas are also seen with

neurofibromatosis type II Neurofibromatosis type II (also known as MISME syndrome – multiple inherited schwannomas, meningiomas, and ependymomas) is a genetic condition that may be inherited or may arise spontaneously, and causes benign tumors of the brain, spinal cord, ...

Signs and symptoms

Source: * severe headache * visual loss (due to

papilledema Papilledema or papilloedema is optic disc swelling that is caused by increased intracranial pressure due to any cause. The swelling is usually bilateral and can occur over a period of hours to weeks. Unilateral presentation is extremely rare. In ...

) * vomiting * bilateral

Babinski sign The plantar reflex is a reflex elicited when the sole of the foot is stimulated with a blunt instrument. The reflex can take one of two forms. In healthy adults, the plantar reflex causes a downward response of the hallux (flexion). An upward re ...

* drowsiness (after several hours of the above symptoms) * gait change (rotation of feet when walking) * impaction/constipation * back flexibility

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

pseudorosette In histopathology, a palisade is a single layer of relatively long cells, arranged loosely perpendicular to a surface and parallel to each other. A rosette is a palisade in a halo or spoke-and-wheel arrangement, surrounding a central core or hub. ...

s 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, despite their name suggesting an ependymal origin. Image:Myxopapillary ependymoma - high mag.jpg,

Micrograph A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a m ...

of a myxopapillary ependymoma.

HPS stain In histology, the HPS stain, or hematoxylin phloxine saffron stain, is a way of marking tissues. HPS is similar to H&E, the standard bearer in histology. However, it differentiates between the most common connective tissue (collagen) and musc ...

. File:Ependymom ax T2.jpg, Ependymoma of 4.ventricle in MRI. File:Ependymom sag FLAIR.jpg, Ependymoma of 4.ventricle in MRI. File:Ependymom cor T1KM.jpg, Ependymoma of 4.ventricle in MRI. Left without, right with contrast-enhancement.

Ependymoma tumors

Ependymomas make up about 5% of adult intracranial

glioma A glioma is a type of tumor that starts in the glial cells of the brain or the spine. Gliomas comprise about 30 percent of all brain tumors and central nervous system tumours, and 80 percent of all malignant brain tumours. Signs and symptoms ...

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 is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary inc ...

. They may also arise in the spinal cord, conus medullaris and supratentorial locations. 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 10% of ependymomas are benign myxopapillary ependymoma (MPE). MPE is a localized and slow-growing low-grade tumor, which originates almost exclusively from the lumbosacral nervous tissue of young patients. On the other hand, it is the most common tumor of the lumbosacral canal comprising about 90% of all tumoral lesions in this region. Although some ependymomas are of a more anaplastic and malignant type, most of them are not anaplastic. Well-differentiated ependymomas are usually treated with surgery. For other ependymomas, total surgical removal is the preferred treatment in addition to radiation therapy. The malignant (anaplastic) varieties of this tumor, malignant ependymoma and the ependymoblastoma, are treated similarly to

medulloblastoma Medulloblastoma is a common type of primary brain cancer in children. It originates in the part of the brain that is towards the back and the bottom, on the floor of the skull, in the cerebellum, or posterior fossa. The brain is divided into two ...

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 The septum pellucidum (Latin for "translucent wall") is a thin, triangular, vertical double membrane separating the anterior horns of the left and right lateral ventricles of the brain. It runs as a sheet from the corpus callosum down to the f ...

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 A teratoma is a tumor made up of several different types of tissue, such as hair, muscle, teeth, or bone. Teratomata typically form in the ovary, testicle, or coccyx. Symptoms Symptoms may be minimal if the tumor is small. A testicular ter ...

or may be confused with a

sacrococcygeal teratoma Sacrococcygeal teratoma (SCT) is a type of tumor known as a teratoma that develops at the base of the coccyx (tailbone) and is thought to be primarily derived from remnants of the primitive streak. Sacrococcygeal teratomas are benign 75% of the ...

Treatment

Guidelines for initial management for ependymoma are maximum surgical resection followed by radiation. Chemotherapy is of limited use and reserved for special cases including young children and those with tumor present after resection. Prophylactic craniospinal irradiation is of variable use and is a source of controversy given that most recurrence occurs at the site of resection and therefore is of debatable efficacy. Confirmation of cerebrospinal infiltration warrants more expansive radiation fields. Prognosis of recurrence is poor and often indicates palliative care to manage symptoms.

References

External links

Brain and Spinal Tumors: Hope Through Research (National Institute of Neurological Disorders and Stroke)
{{Authority control Brain tumor Rare cancers Infectious causes of cancer Ventricular system