Neoplasms

Question 1

What areas of the brain are most common for brain tumors in adults and in children?

Answer 1

Adults: supratentorial
Children: infratentorial

Question 2

Recap from stroke lectures: which kind of stroke has a more rapid increase in intracranial pressure?

Answer 2

Hemorrhagic stroke –bleeding induces a fast rise in ICP, whereas inflammation in an ischemic stroke develops over a couple days.

Question 3

What are symptoms of increase in ICP?

Answer 3

Headache
Nausea and vomiting
Lethargy

Question 4

“Gliomas” includes malignancies from which cells?

Answer 4

Astrocytoma
Ependymoma
Oligodendroglioma

Question 5

While tumors arise from errant stem cells, they tend to recapitulate ____________.

Answer 5

certain lineages (such as astrocytes, ependymal cells, etc.)

Question 6

What is the only glioma that has a grade I designation?

Answer 6

Astrocytoma (called pilocytic astrocytoma)

Question 7

“Anaplastic gliomas,” regardless of the lineage type, are always grade _________.

Answer 7

III

Question 8

Glioblastomas are always grade _____.

Answer 8

IV

Question 9

The most common subtype of glioma seen in children is __________.

Answer 9

pilocytic astrocytoma

Question 10

What age group are posterior fossa neoplasms more commonly seen in?

Answer 10

Children

Question 11

Describe the histologic appearance of pilocytic astrocytoma.

Answer 11

Long, bipolar cells with hairlike processes
Rosenthal fibers (pink, corkscrew fibers)
Stains for GFAP (glial fibrillary acidic protein)

Question 12

BRAF:________ is a common fusion for pilocytic astrocytoma.

Answer 12

KIAA; this protein’s function is not known, but when fused with BRAF it constitutively activates it

Question 13

Describe the gross appearance of pilocytic astrocytomas.

Answer 13

Cystic

Well-demarcated

Question 14

What feature makes a diffuse astrocytoma an anaplastic astrocytoma?

Answer 14

Increased mitoses

Question 15

Diffuse astrocytomas appear in a “___________ array.”

Answer 15

patternless (“like someone threw Cheerios all over the floor”)

Question 16

Describe the gross appearance (and clinical implication thereof) of diffuse astrocytomas.

Answer 16

Poor-demarcation

This makes them not amenable to surgical resection.

Question 17

Anaplastic oligodendrogliomas usually have markedly elevated _________.

Answer 17

MIB-1

Question 18

What genetic marker is unique to oligodendrogliomas?

Answer 18

1p19q co-deletions

Question 19

Gangliogliomas are ______-growing and as such grade _____.

Answer 19

slow; I

Question 20

Gangliogliomas are a common source of _________.

Answer 20

temporal-lobe seizures (these neoplasms almost always develop in the temporal lobes)

Question 21

Medulloblastoma is, by definition, a tumor of the ___________.

Answer 21

cerebellum

Question 22

Medulloblastomas are more common in what demographic?

Answer 22

males; children under 16

Question 23

Children younger than what age cannot be given radiation therapy?

Answer 23

One year

Question 24

What is the only brain tumor that is staged?

Answer 24

Medulloblastoma

Question 25

What chromosome is commonly affected in medulloblastoma?

Answer 25

17

Question 26

"Rosettes" are histologically found in what CNS tumors?

Answer 26

Medulloblastoma and ependymoma

Question 27

How do cerebellar external granule cells migrate?

Answer 27

Inward along the gradient of sonic hedgehog

Question 28

What kind of herniation does doing an LP on a person with increased ICP cause?

Answer 28

Tonsillar

Question 29

What demographic has the highest rate of meningioma?

Answer 29

Females, 50 - 59 (MENingiomas at MENopause)

Question 30

What cranial nerves have Schwann cells?

Answer 30

3 - 12

Question 31

True or false: the neoplasm with long, hairlike cells that have Rosenthal fibers has a strong tendency to dedifferentiate and upgrade.

Answer 31

False. This tumor (the pilocytic astrocytoma) is grade I and usually remains so

Question 32

What cancer usually presents in the 4th ventricle in adults and the lateral ventricles in children?

Answer 32

Choroid plexus papilloma

Question 33

Two CNS neoplasms almost always possess IDH1 mutations: _____________.

Answer 33

astrocytomas and oligodendrogliomas

Question 34

What is an astrocytoma without IDH1/2 mutations?

Answer 34

Glioblastoma

Question 35

_____________ often presents with a "chicken wire" pattern.

Answer 35

Oligodendroglioma

Question 36

Today, diagnosis of oligodendroglioma requires ______________.

Answer 36

detection of LOH 1p, 19q

Question 37

Which grades of gliomas demonstrate necrosis?

Answer 37

Only grade IV (by definition)

Question 38

True or false: LOH 1p, 19q predicts better outcomes.

Answer 38

True

Question 39

The most common glioma is ____________.

Answer 39

glioblastoma multiforme (unfortunately)

Question 40

How do most glioblastoma multiforme tumors arise?

Answer 40

De novo (i.e., they do not evolve out of lower grade tumors)

Question 41

Of the 180,000 CNS malignancies per year, how many are primary?

Answer 41

1/6

Question 42

What genetic signature do diffuse astrocytomas have?

Answer 42

IDH mutations and loss of 17p

Question 43

Loss of PTEN and amplification of EGFRvIII often causes ___________.

Answer 43

glioblastoma multiforme

Question 44

Isocitrate dehydrogenase usually produces __________; the mutants, however, produce ____________.

Answer 44

alpha-ketoglutarate; 2-hydroxyglutarate

Question 45

Medulloblastomas are thought to develop from __________ cells.

Answer 45

external granule layer