Neurology- Childhood Brain Tumors Flashcards
What are some common childhood primary brain tumors?
Pilocytic (low-grade) astrocytoma
Medulloblastoma
Ependryoma
Cranippharyngioma
Describe Pilocytic (low-grade) astrocytomas
these are usually well circumscribed tumors, most often found in the posterior fossa (e.g. cerebellum)
may be supratentorial
What is the prognosis for a Pilocytic (low-grade) astrocytoma?
benign; good prognosis
Pilocytic (low-grade) astrocytoma stain positive for what?
GFAP
What are the main histo findings of a Pilocytic (low-grade) astrocytoma?
Rosenthal fibers (eosinophilic, corkscrew fibers)
Cystic + solid (gross)
Describe medulloblastomas
these are highly malignant cerebellar tumors that are a form of primitive neuroectodermal tumors
How can medulloblastomas present?
they can comrpess the 4th ventricle, causing hydrocephalus
can send “drop METs” to the spinal cord
Describe the histo of medulloblastomas
Homer-Wright rosettes
small blue cells
What is an ependymoma?
a tumor arising from ependymal cells most commonly found in the 4th ventricle (poor prognosis)
Describe the histo of ependymomas
perivascular rosettes
rod-shaped blepharolasts (basal ciliary bodies) found near nucleus
What are craniophayngiomas?
benign childhood tumors often confused with pitutiary adenomas (both can cause bitemporal heminopia)
this is the most common childhood supratentorial tumor
What are craniophayngiomas derived from?
Rathke pouch
What are the major herniation syndromes?
Cingulate herniation (subfalcine)
Downward transtentorial (central) herniation
Uncal herniation
Cerebellar tonsillar herniation into the foramen magnum
Describe Cingulate herniation (subfalcine)
can compress the ACA
Describe Downward transtentorial (central) herniation
caudal displacement of the brain stem leading to rupture of the paramedian basilar artery branches resulting in duret hemorrhages (usually fatal)
