Brain tumors 0426

Question 1

primary tumors

Answer 1

rarely undergo mets.
clinical sx due to mass effect - seizures, dementia, focal lesions.
prognosis based on grade - bromodeoxyuridine uptake indicates prolif rate.

Question 2

adult primary tumors

Answer 2

supratentorial

*half of adult brain tumors are mets from other organs - well circumscribed, at gray-white junction

Question 3

childhood primary tumors

Answer 3

infratentorial

Question 4

gliobastoma multiforme

grade IV astrocytoma

Answer 4

adult primary tumor - most common.
grave prognosis < 1 yr.

CEREBRAL HEMISPHERES.
can cross corpus callosum (butterfly glioma).
stain astrocytes for GFAP.

Question 5

glioblastoma multiforme - histo

Answer 5

pseudopalisading pleomorphic tumor cells - bordering central areas of necrosis and hemorrhage.

Question 6

glioblastoma multiforme - sx

Answer 6

“head fullness” and HA when standing

Question 7

meningioma

Answer 7

adult primary tumor.
2nd most common.
benign, resectable.

CONVEXITIES of HEMISPHERES and PARASAGITTAL REGION.

from ARACHNOID cells external to brain.

Question 8

meningioma - histo

Answer 8

spindle cells concentrically arranged in whorled pattern.

PSAMMOMA BODIES (laminated calcifications).

Question 9

schwannoma

Answer 9

adult primary tumor.
3rd most common.
benign, resectable.

SCHWANN CELL ORIGIN.
often localized to CN VIII - acoustic neuroma (hearing loss, tinnitus).
cerebellopontine angle.
S-100 positive.

Question 10

schwannoma assoc. with?

Answer 10

NF type 2 - bilateral schwannomas.

Question 11

oligodendroglioma

Answer 11

adult primary tumor.
rare, slow growing.
malignant but well-circumscribed.

FRONTAL LOBE.

Question 12

oligodendroglioma - histo

Answer 12

delicate chicken-wire capillary pattern.

oligodendrocytes appear “FRIED EGG” cells with round nuclei and clear cytoplasm. often calcified.

Question 13

pituitary adenoma

Answer 13

adult primary tumor.
usually PROLACTINOMA.
pressure on optic chiasm = bitemporal hemianopia.

sequelae: hyper or hypopituitarism.

Question 14

pilocytic (low grade) astrocytoma

Answer 14

childhood primary tumor.
well-circumscribed, benign.

POSTERIOR FOSSA (cerebellum).
GFAP positive.

Question 15

pilocytic astrocytoma - histo

Answer 15

rosenthal fibers - eosinophilic astrocyte processes that look like corkscrew.

gross: cystic and solid.

Question 16

medulloblastoma

Answer 16

childhood primary tumor.
highly malignant CEREBELLAR tumor.
radiosensitive.
primitive neuroectodermal tumor (PNET).
can cross 4th ventricle, cause hydrocephalus.

Question 17

medulloblastoma - histo

Answer 17

small round blue cells.
Homer-Wright rosettes.

gross: solid

Question 18

ependymoma

Answer 18

childhood primary tumor.
ependymal cell tumor in 4th ventricle.
can cause hydrocephalus.
poor prognosis.

Question 19

ependymoma - histo

Answer 19

perivascular pseudorosettes.

rod-shaped blepharoblasts (basal ciliary bodies) near nucleus.

Question 20

hemangioblastoma

Answer 20

childhood primary tumor.
most often cerebellar.
part of von Hippel Lindau syndrome when found with RETINAL ANGIOMA.

can produce EPO - secondary polycythemia.
foamy cells and high vascularity.

Question 21

craniopharyngioma

Answer 21

childhood primary tumor.
most common SUPRATENTORIAL tumor.
confused with pituitary adenoma.
also can cause bitemporal hemianopia.

derived from remnants of RATHKE’s POUCH. calcification common - tooth enamel-like.