brain tumors

Question 1

intra-axial tumor

Answer 1

w/in brain parenchyma

Question 2

extra-axial tumor

Answer 2

not in brain parenchyma

Question 3

NF1

Answer 3

aka von recklinghausen 
NF1 on 17q
plexiform neurofibroma
MPNST
optic and other gliomas
phenochromocytoma
GIST
cafe au lait spots

Question 4

NF2

Answer 4

NF2 on 22q
vesticular and PN schwannoma
menigiomas

Question 5

TS

Answer 5

TSC1 on 19q
TSC2 on 16p
SEGA
renal AMLs
lung LAM
cardiac rhabdomyomas

Question 6

VHL

Answer 6

VHL on 3p
hemangioblastoma
renal cell carcinoma
pheochromocytomas

Question 7

Li-fraumeni

Answer 7

TP53 on 17p
astrocytomas
breast carcinoma
bone and soft tissue sarcomas

Question 8

turcot syndrome

Answer 8

FAP on 5p
medulloblastoma
GBM
GI polyps 
colorectal CA

Question 9

gorlin syndrome

Answer 9

PTCH on9q
desmoplastic medulloblastoma
nevoid BCC
odontogenic keratocysts

Question 10

what are the most common CNS tumors

Answer 10

meningiomas 35%
glioblastomas 17%
pituitary 13%
astrocytomas 7%

Question 11

meningiomas

Answer 11

arise for arachnoid but anchor to dura
F>M
loss of chr 22 -> loss of merlin 
multiple in NF2 and post radiation
good prognosis
locally invades into bone, but most are benign
can be fatal dependent upon location

Question 12

histo characteristics of meningiomas

Answer 12

calcifications
whorls
psammoma bodies

Question 13

gliomas

Answer 13

most common grp of priamry brain tumors
include:
astrocytomas
oligodendrogliomas
ependymomas
thought to derive from stem cells in periventricular area

Question 14

pilocytic astrocytoma

Answer 14

grade I astrocytoma
most frequent glial tumor of kids
almost alwasys in cerebellum
well circumscribed
cystic w/solid tumor inside cyst
increased ICP
TP53 mutations very rare
good prognosis

Question 15

diffuse astrocytoma

Answer 15

ill defined, infiltrating
any site in CNS
seizures, HA, focal signs
progress
no matter what 5-7yr survival

Question 16

astrocytoma grade IV

Answer 16

usually called glioblastoma

Question 17

grade II astrocytoma mutations

Answer 17

TP53

Question 18

grade III astrocytomas

mutations

Answer 18

aka anaplastic astrocytoma

TP53

Question 19

secondary IV glioblastomas mutations

Answer 19

IDH1 and IDH2 point mutations
LOH
EGFR
p16 deletion
TP53
PTEN

Question 20

primary glioblastoma

Answer 20

do not go thru other phases, originate as grade IV
LOH
EGFR (more then progressive
p16 deletion
TP53 (fewer then progressive)
PTEN

Question 21

oligodendroglioma

Answer 21

ill defined, infiltrating
supratentorial, mostly white matter
frontal most common
4th-5th decades
long history of HAs, seizures
frequently calcified
prognosis is 6yrs
fried egg appearance on histo

Question 22

Oligodendroglioma mutations

Answer 22

IDH1/2 mutaiton in 90% and portend better prognosis

deletions of chrom 1p with 19p can be used for Tx

Question 23

medulloblastoma

Answer 23

grade IV malignant tumor of kids
most in vermis
ataxia and signs of ICP
tendency to disseminate via subarachnoid space and CSF
can live to 5 yrs old

Question 24

medulloblastoma CSF

Answer 24

increased pressure
high protein
low glucose

Question 25

cerebral lymphoma

Answer 25

rare as primary tumor
typically a diffuse large B cell lymphoma
almost all are immunocompromised pts who are EBV +
meningneal spread common
corticosteroid Tx so successful tumor usually disappears

Question 26

ependymoma

Answer 26

slow growing tumors
hydrocephalus, increased ICP, ataxia
well circumscribed, but can disseminate

Question 27

schwannoma

Answer 27

much much more common in PNS
does occur in vestibular system
4-6th decades
solitary
b/l in NF2
benign