Adult and childhood primary brain tumors

Question 1

Glioblastoma multiforme (grade IV astrocytoma)

Answer 1

Adult
Most common 1st brain tumor
Malignant with pheomorphic tumor cells
Border central areas of necrosis and hemorrhage

Question 2

Meningioma

Answer 2

Adult
2nd most common 1’ brain tumor
Most often occurs in convexities of hemispheres
(near surfaces of brain) and parasagittal region

Arise from arachnoid cells, are extra axial (external to brain parenchyma), and may have a dural attachement (tail)

Typically benign and resectable.
Often asymptomatic; may present with seizures or focal signs.

Spindle cells concentrically arranged in a whorled pattern: psammoma bodies (laminated calcification)

Question 3

Schwannoma

Answer 3

Adult
3rd most common 1’ brain tumor
Schwann cell origin; often localized to CN 8 -> acoustinc schwannoma (aka acoustic neuroma).

Resectable or treated with stereotatic radiosurgery.
Usually found at cerebellopontine angle, S-100 positive.

Bilateral acoustic schwannoma found in NF2

Question 4

Oligodendroglioma

Answer 4

Adult
Relatively rare, slow growing.
Most often in frontal lobes
Chicken wire capillary pattern.
Oligodendrocytes = fried egg cell, round nuclei with clear cytoplasm. Often calcified in oligodendroglioma

Question 5

Pituitary adenoma

Answer 5

Adult
Most commonly prolactinoma
Bitemporal hemianopsia
Due to pressure on optic chiasm and hyper- and hypo
pituitarism are sequelae.

Question 6

Pilocytic (low grade) astrocytoma

Answer 6

Childhood
Well circumscribed, often in posterior fossa (cerebellum)
May be supratentorial
GFAB positive
Benign good prognosis

ROSENTHAL FIBERS: eosinophilic corkscrew fibers.
Cystic  solid (gross)

Question 7

Medulloblastoma

Answer 7

Childhood
Highly malignant cerebellar tumor
A form of primitive neuroectodermal tumor
Can compress 4th ventricle, causing hydrocephalus
Can send drop mets to spinal cord

Homer-Wright rosettes. (vs perivascular pseudorosette of ependydymoma)

Solid (gross), small blue cells (histology)
Radiosensitive

Question 8

Ependymoma

Answer 8

Ependymal cell tumors most commonly found in 4th ventricle
Can cause hydrocephalus
Poor prognosis

Characteristic perivascular pseudorosettes
Rods shaped blepharoplasts (basal ciliary bodies)
Found near nucleus

Question 9

Hemagioblastoma

Answer 9

Most often cerebellar, associated with VHL syndrome when found with retinal angiomas

Can produce EPO-> 2nd polycythemia

Foamy cells and high vascularity are characteristic

Question 10

Craniopharyngioma

Answer 10

Benign childhood tumor, confused with pituitary adenoma
(can also cause bitemporal hemianopsia)
Most common childhood supratentorial tumor

Derived from Remnants of Rathe’s pouch
Calcification is common (tooth enamel like)