Brain Tumor Genetic Disorders

Question 1

Mutation of TP53 (ch 17).

Answer 1

Li-Fraumeni syndrome

Question 2

Brain tumor types with Li-Fraumeni.

Answer 2

Glioma

• Astrocytoma
• Medulloblastoma

Question 3

Mutation in TSC1 (ch9) and TSC2 (ch16).

Answer 3

Tuberous sclerosis

Question 4

Brian tumor types with Tuberous sclerosis.

Answer 4

*Subependymal Giant Cell Astrocytoma
Cortical Tubers
Glioma

Question 5

What is the mnemonic for Tuberous Sclerosis?

Answer 5

HAMARTOMAS:
Hamartomas in CNS and skin
Angiofibromas
Mitral regurgitation
Ash-leaf spots
Rhabdomyoma (cardiac)
Tuberous Sclerosis
dOminant
Mental retardation
Angiomyolipoma (renal)
Seizures/Shagreen patches

Question 6

What chromosome is NF1 located on?

Answer 6

17q11

Question 7

What chromosome is NF2 located on?

Answer 7

22q12

Question 8

What brain tumors are associated with NF type 1?

Answer 8

*Glioma (optic nerve)
Astrocytoma
Glioblastoma
Ependymomas

Question 9

What brain tumors are associated with NF type 2?

Answer 9

*Schwannoma (bilateral acoustic neuromas)
Meningioma
Ependymomas

Question 10

What does NF1 code for?

Answer 10

neurofibromin (negative regulator of Ras)

Question 11

What chromosome is RB1 located on?

Answer 11

13q14

Question 12

What chromosome is VHL located on?

Answer 12

3

Question 13

What tumors are seen in Von Hippel Lindau disease?

Answer 13

Hemangioblastomas

Question 14

What does VHL do?

Answer 14

if mutated, it allows constitutive expression of HIF and activation of angiogenic growth factors

Question 15

What is the mutation in Gorlin syndrome (nevoid basal cell carcinomas)?

Answer 15

PTCH mutations

Question 16

What type of brain tumor is seen in those with Gorlin syndrome?

Answer 16

medulloblastoma

Question 17

What is the mutation in Cowden syndrome?

Answer 17

loss of function in PTEN (leading to hyperactivity of mTOR pathway)

Question 18

What types of brain tumors are seen in Cowden syndrome?

Answer 18

Dysplastic gangliocytoma of cerebellum

Question 19

What is the mutation in Turcot syndrome?

Answer 19

germline mutation in APC gene or mismatch repair in hMLH1 or hPMS2

Question 20

What types of brain tumors do patients with Turcot syndrome get?

Answer 20

Medulloblastomas

Glioblastoma multiforme