31b - Pediatric Brain Tumors Flashcards
(38 cards)
Where is the most common site for PED tumors: supratentoria, infretentorial, or midline?
infratentorial most common in PEDs.
What are supratentorial peds tumors?
suprasellar (chiasmal glioma, craniopharyngioma)
hemispheric (astrocytoma)
pineal
What are infratentorial tumors in peds?
Most common are cerebellum and 4th ventricle
>posterior fossa (medulloblast, astrocy, ependy, and glioma)
What is most common pediatric solid tumor?
brain tumor
What is survival rate for brain tumors in 1st decade?
65%
What is most common Peds tumor?
astrocytoma>PNET>gliomas>ependymomas
What are Cowden (xPTEN) syndromes risks for?
high mTOR. dysplastic gangliocytoma in cerebellum
What are nevoid basal cell carcinoma/gorlin syndrome risks for?
medulloblastoma (ch. 9, PTCH mutation)
What is an APC gene mutation a risk for?
turcot syndrome, medulloblastoma and GBM
What is likely location of a tumor causing localized seizures and hemiparesis?
supratentorial
What symptoms would you expect for a midline tumor?
endocrinopathies, hydrocephalus (early AM headache with n/v, bulging fontanelle, sundowning eyes, CN6 palsy)
What are signs of a infratentorial tumor?
high ICP due to compression of 4th ventrical.
papilledema w/blurring of optic disk
What are signs of brainstem tumor?
diplopia, dysarthria, dysphagia. crossed weakness (lesion rostral to pyramidal decussation) = ipsilateral CN function and contralateral UMN findings.
What is JPA? Where is it commonly olcated?
juvenile pilocystic astrocytoma (grade 1).
usually supra or infratentorial, most on posterior fossa.
What can JPA progress to?
GBM
What is pathogenesis of JPA?
mutation of BRAF (fusion or v600e) and NF1 cause oncogenic process of MAPK path.
mtuations activate RAF and MAPK pathways that incrase nuclear transcription.
Where are BRAF fusion mutation tumors common?
BRAF v600e?
fusion = cerebellum v600e = extracerebellum
Whhere are NF1 mutation types of JPA common?
optic pathways
What is gross appearance of JPA?
cYSTIC.
what is microscopic pathology of JPA?
pilocytic, hair like projections off neoplastic cells ROSENTHAL FIBERS that are GFAP+.
Hyalinization of blood vessels
What is prognosis for JPA?
good, it is low grade
What is medulloblastoma?
a highly malignant primitive tumor of the CEREBELLUM.
What is PNET?
highly malignant primitive tumor of the CEREBRUM
What are histochemical markers for medulloblastoma and PNET?
TrkC, Erb, C-myc, neurotrophinin
