What is ependymoma?

➢ Bright mass with cystic areas fills the fourth ventricle (most common site of an ependymoma in children). ➢ This neoplasm arises from the ependymal lining cells. ➢ Enlargement of the tumor with blockage of the CSF flow in the fourth ventricle may produce obstructive (noncommunicating) hydrocephalus. ➢Although ependymomas tend not to be invasive, they can be close to vital brain stem structures, and they can spread into the CSF and can be difficult to eradicate. ➢In adults, most ependymomas are found within the spinal cord, and some are associated with neurofibromatosis type 2 ➢ The microscopic appearance of an ependymoma from the fourth ventricle reveals a rosette pattern with the tumor cells arranged around a central vascular space (perivascular pseudorosette). ➢ The ependymal processes stain positively for GFAP. ➢ A particular variety : myxo- papillary ependymoma typically arises in the filum terminale of the spinal cord of an adult. ➢The cuboidal tumor cells are arranged around papillations that have a myxoid connective tissue core.