CNS Brain Tumors

Question 1

Pilocytic astrocytoma

Answer 1

Grade I
Most common in children.
Like the posterior fossa
BRAF mutation (favorable prognosis)
Distinct from diffuse astrocytoma 
Noninfiltrative
Often have cystic component

Question 2

Ganglioglioma

Answer 2

Grade I
Often temporal lobe
Often cystic 
Well demarcated
Calcification

Question 3

Choroid plexus papilloma

Answer 3

Grade I
Morphologically similar to choroid plexus, but more papillary formations
Most common in lateral ventricles in children
4th ventricle in adults
Can cause hydrocephalus through blockage of CSF flow

Question 4

Diffuse astrocytoma

Answer 4

Grade II
IDH and TP53 mutation
Young adults
Surgery rarely effective

Question 5

Mitosis level measured by _______

Answer 5

MIB1

Question 6

Anaplastic astrocytoma

Answer 6

Class III
IDH and TP53 mutation AND 9p loss
Increased mitotic rate
Does not typically show necrosis

Question 7

Oligodendroglioma

Answer 7

Grade II
Obscures cortical white/gray border
Seizures
Fried egg appearance
IDH AND 1p/19q codel

Question 8

Ependyoma

Answer 8

Grade II
Ependymal cells in ventricles (4th)
First two decades of life
Obstructive hydrocephalus

Question 9

Glioblastoma

Answer 9

Grade IV
Synonymous with astrocytoma 
Primary: lots of different mutations
Secondary: IDH, 10q loss
Nuclear abnormalities
Mitotic activity 
Micro vascular 
Proliferation necrosis

Question 10

What do we do for grade II?

For grade III/IV?

Answer 10

Resect and observe

Resect and radiate

Question 11

Medulloblastoma

Answer 11

Grade IV
Usually in children
External granular cell layer of cerebellum

Question 12

Meningiomas

Answer 12

Most grade I
Attached to dura
Arachnoidal cells
Solid tumor
NF2 mutation

Question 13

Schwannomas

Answer 13

Commonly on roots of spinal cord

Question 14

Familial Tumor Syndromes

Answer 14

NF1/2 (Schwannomas and meningiomas)
Tuberous sclerosis
Li-fraumendi (p53)