Low Grade Gliomas

Question 1

What are the two most common types of LGG in childhood

Answer 1

Pilocytic astrocytoma

Diffuse fibrillary astrocytoma

Question 2

What are 5 other types of LGG that occur in pediatric a

Answer 2

SubependymAl giant cell astrocytoma
Pleiomorphic xanthroastrocytoma
Pilomyxoid astrocytoma
Oligodendrioglioma
Ganglioglioma

Question 3

What is the most common cytogenetic feature in LGG ( especially JPA) in childhood?

Answer 3

BRAF KIAA1549 fusion

Question 4

What is another mutation that is seen commonly and what types of LGG is thus in

Answer 4

BRAF V600E

Seen often in pleiomorphic xanthroastrocytoma and ganglioglioma

Question 5

What are some other types of mutations that can occur in a LGG?

Answer 5

Anything in the RAS-RAF- MEK- ERk pathway

FGFR1 in DNET
PTPN11, KRAS

CDK2NA- poor prognostic

Question 6

What type of cytogenetics change is prognostic in oligodendrogliomas ( especially adult type)?

Answer 6

1p and 19q co deletion associated with a good prognosis

Question 7

What are the most common locations for the various LGG?

Answer 7

JPA and diffuse fibrillary- cerebellum
Pleiomorphic XA- temporal lobe
Pilomyxoid A- hypothalamus/ chiasm
Oligodendroglioma- frontal lobe
Ganglioglioma - supratentorial

Question 8

What is the PFS for completely resected and incompletely resected JPAs?

Answer 8

Completely resected- 90%

Incomplete- 40-50%

Question 9

What are three chemo regimens you can use to treat LGGs?

Answer 9

Vinblastine monotherapy
Carboplatin/vincristine
TPCV

Question 10

What are 5 prognostic factors in LGG?

Answer 10

Histology- JPA better
Biology BRAF fusion associated with lower progression to HGG then the BRAF point mutation 
Complete resection better prognosis
CDKN2A - worse prognosis 
NF-1 has better prognosis

Question 11

What are categories of gliomas?

Answer 11

Astrocytoma

Oligodendroglioma

Ependymoma

Mixed glial- neuronal tumors