CNS: GLIOMA TUMORS
infiltrating astrocytomas
Most common brain tumor in adults (80%) usually found in cerebral hemisphere Often presents in 4-6 decade most common presenting signs and symptoms are seizures, headaches, and focal neurologic deficits
diffusely infiltrating astrocytomas localized astrocytomas
What are the two major categories of astrocytic tumors?
pilocytic astrocytomas
What is the most commom localized astrocytoma?
pilocytic astrocytomas
distinguished from the other types by their gross and microscopic appearance and relatively benign behavior They typically occur in children and young adults, and are usually located in the cerebellum but may also appear in the floor and walls of the third ventricle, the optic nerves, and occasionally the cerebral hemispheres neurofibromatosis type 1 show functional loss of neurofibromin (not observed in sporatic forms)
Brainstem Glioma
occur most often in the first 2 decades of life intrinsic pontine gliomas (the most common) cervicomedullary junction tumors dorsally exophytic gliomas
Gliomas
the most common group of primary brain tumors include astrocytomas, oligodendrogliomas, and ependymomas. characteristic histologic features that form the basis for the classification derive from progenitor cell
infiltrating astrocytomas
Clinical deterioration usually occurs after emergence of a more rapidly growing tumor of higher histologic grade The prognosis for individuals with glioblastoma is very poor (usually a year or less when diagnosed)
hydrocephalus
Posterior fossa ependymomas often manifest with ______ secondary to progressive obstruction of the fourth ventricle
Oligodendroglioma
These are infiltrating gliomas comprised of cells that resemble oligodendrocytes common in the fourth and fifth decades lesions are found mostly in the cerebral hemispheres, with a predilection for white matter average survival of 5 to 10 years anaplastic = worse prognosis
Ependymomas
are tumors that most often arise next to the ependyma-lined ventricular system, including the oft-obliterated central canal of the spinal cord In adults the spinal cord is the most common location (frequent in NF2) Fourth ventricle most common in 20 or under Removal is possible if in a favorable position/location (spinal cord)
Pleomorphic Xanthoastrocytoma
occurs most often in the temporal lobe in children and young adults, usually with a history of seizures presence of abundant reticulin deposits, relative circumscription, and chronic inflammatory cell infiltrates, along with the absence of necrosis and mitotic activity, distinguish this tumor from more malignant types
