Neuro Oncology, ASPHO Flashcards
in terms of prevalence in peds haem/onc, where do brain tumours fall?
most common SOLID malig…second most common malig overall after leukemia
what is the most common brain tumour overall?
- Astrocytomas are the most common brain tumor overall (most commonly low‐grade)
- Medulloblastomas are the most common “malignant” brain tumor
msot common malig brain tumour?
medulloblastoma
CNS tumours: prevalence in boys vs girls?
overall more prevalent in BOYS…1.2:1
5 survival rate for peds CNS tumours?
70-75%…but misleading because some worse survival outcomes and high morbidity
in what ways are peds brain tumours diff from adult ones?
histo
bio
tx
outcomes
etiology of brain tumours generally unknown excepet in what TWO cases?
history of ionizing radiation…typically hx of CNS rads from past CNS tumour or CNS leukemia…..or Genetic brain tumour predisopsoition syndrome
give 8 predisposition syndromes
NNTLGFRR
Nada’s Tumours: Never Let Go of Really Fresh Research
NF1, NF2, Tuberous sclerosis, Li Fraumeni, Gorlin’s syndrome= nevoid basal cell carcinoma sydnrome, Familial Adenomatous Polyposis (Gardner’s Turcot’s), Rhabdoid tumour predisposition syndrome, retinoblastoma (germline)
Neurofibromatosis Type 1: give gene, CNS lesion, other findings
- NF1
- low grade glioma (optic pathway and brainstem)
- Cafe au lait spots, lisch nodules, axillary freckling
Neurofibromatosis type 2: give gene, CNS lesion, other findings
- NF2
- BIlateral acoustic schwannomas, meningiomas, ependymomas
- increased risk of cataracts and seizures
Tuberous Sclerosis: give genes, characteristic CNS lesion, other findings
- TSC1 and TSC2
- Subependymal giant cell astrocytoma= SEGA
- increased risk fo skin adn renal growths
Li Fraumeni: give gene, characteristic CNS lesion, other findings
- TP53
- malig glioma, choroid plexus carcinoma
- nuemrous cancers at younger ages (breast, sarcoma, adrenal cortical carcinoma)
Gorlin’s syndrome= nevoid basal cell ca syndrome…give gene, characteristic cns lesion, other findings
- PTCH
- medulloblastoma
- basal cell ca
rhabdoid tumour predispositon syndrome…give gene, CNS lesion, other findings
- SMARCB1 and SMARCA4
- ATRT= atypical teratoid rhabdoid tumour
- rhabdoid tumours in kidney, schwannomatosis, usually <1 year at dx
retinoblastoma (germline): give gene, charactersitic CNS lesion, other findings
- trilaeral Retinoblastoma (unilateral or bilateral retinoblastoma + pineoblastoma)
- pineoblastoma in these cases is usually dx’ed after the Rb but often before age of 5
majority of brain tumours in kids are in ____ region…what fraction of tumours is this? what’s included in this region?
infratentorial; 2/3; cerebellum, pons, medulla
where’s the lesion: autonomic dysfunction like temp reg, thirst, hunger affected…endocrinopathies
hypothalamus
where’s the lesion? poor/loss of vision
occipital lobe
where’s the lesion? decrased sense of touch/pain, poor spatial and visual perception, poor interpretation of language
parietal lobe
where’s teh lesion? personality changes, decreased motor speech (Broca’s), seizures
frontal lobe
where’s the lesion? ataxia, muscle movement/coordination affected, posture affected
cerebellum
where’s the lesion? weakness/motor control affected, decreased consciousness, sleep/wake cycle affected
thalamus
where’s teh lesion? weakness, cranial neuropathies (III-XII), autonomic dysfunction
brainstem
where’s the lesion? seizures, poor memory, decreased lang comprehension (wernicke’s)
temporal lobe
4 non-localizing neuro onc symptoms?
dev delay
behavioural changes
decline in school perf
sleepiness
5 symptoms/signs of increased ICP?
headache emesis sleepiness/lethargy papilledema full/bulging fontanelle
5 endocrine sx associated with brian tumours
diabetes insipidus hypoT4 wt gain or loss panhypopit precocious puberty
low grade gliomas include WHO grade __ and ___ ___ tumours
1;2;glial
name 5 LGGs
pilocytic astrocytoma oligodendroglioma ganglioma pleomorphic xanthoastrocytoma diffuse fibrillary astrocytoma
LGGs: what % of all brain tumours in kids?
40-50%
give a LGG associated with a cancer predispo
SEGA assocaited with TS!
how do you treat SEGA?
historically with surgery but now MTOR inhibitors are front line
what % of NF1 patients develop a CNS LGG?
15-20%
do you need to biopsy a LGG in NF1?
not if classic appearance
tx indication in NF1-associated LGG?
only treat if affecting vision or other neuro symptoms
tx NF1 associated LGG how?
chemo= first line…usually combo of carboplat and vcr or vinblastine alone
what do you need to AVOID in NF1 patients? (2)
radiation and alkylating chemo! high risk of secondary malig!
dx LGGs how?
biopsy or resection wtih goal of COMPLETE resection whenever possible…exception= NF1 pts with classic appearance of a LGG, typically within the optic pathway (dx can be made by imaging in this case)
other than dx’ing primary, any other eval needed for LGG?
only need additional imaging if symptoms warrant or there’s a specific histo…if there’s back pain, do spine MRI…also pilomyxoid astroctyoma has higher risk of mets, so do spine MRI in this case…do NOT routinely do LP for CSF cytology in LGG
what’s the most common LGG histo?
pilocytic astrocytoma
pilocytic astromcytoma appears how?
low-mod cellularity, GFAP+, dense fibrillary areas…characertized by ROSENTHAL fibers!!!! =astrocytic cytoplasmic inclusions that are corkscrew shaped and eosniophililc on H and E
aberrations of what pathway are most common in LGG?
MAPK
MAPK pathway starts with FGFR…waht are teh 4 next steps?
Ras, BRAF, MEK, ERK
what’s the most common mech of BRAF activation in LGG?
BRAF KIAA1549 fusion…in 60-80%!
other than BRAF fusion give another common BRAF mut in LGG
BRAFV600E…10-15% of pilocytic astrocytoma…also seen in pleomorphic xanthoastrocytoma and ganglioma
Tx LGG how?
try for gross total resection if possible! then observe.:)…if residual disese/no resectable: give chemo= carbo/vcr or vbl alone or combo of thioguanine, procarbazine, ccnu, vcr (PTCV)…should not give this last regimen in NF1 bc procarbazine= alkylating!…radiation effective but avoid in young kids
4 late effects of CNS rads?
neurocognitive changes, endocrine, ototoxicity, secondary malig
what types of targeted therapies are being studied in LGG?
MEK inhibitors, BRAF inhibitors
LGG: OS if GTR?
> 90-95%
COG A9952: compared what? findings?
carboplatin/vcr vs TPCV in LGG…better EFS in TPCV on cure model analysis but more toxic
diencephalic syndrome occurs where?
diencephalon, including thalamus and hypothal
signs and sx of diencphalic syndrome? often caused by?
FTT and emaciation abnormal eye movements and vision issues vomiting hydrocephalus ...oftne caused by LGG
HGG = WHO grade what?
3-4
HGG grade 3=?
anaplastic astrocytoma
HGG gr 4=?
glioblastoma multiforme
HGG more common in kids or adults?
adults
HGGs are more ___ __ __ and have much ___ ___ ___ compared to LGG
resistant to therapy; poorer survival outcomes
3 RFs for HGG?
- previous radiation
- Li Fraumeni syndorme
- Familial Adenomatous Polyposis = APC gene abnormality
dx HGG how?
biopsy/resection and path…except for DIPG!
goal in HGG?
GTR
evaluation for HGG?
- spinal MRI
- NO need for routine LP (CSF cytology)
path in HGG?
"Path in Very Grave CNS Maligs" highly Cellular high Mitotic count Vascular proliferation Pseudopalisating necrosis usually GFAP+
DIPG stands for?
diffuse intrinsic pontine glioma
dx DIPG how?
imaging alone…pons enlarged..typically doesn’t enhance at dx, but this can vary
classic age for DIPG?
5-7 yrs