CNS Neoplasia (Bruch)

Question 1

Which of the following statements about CNS tumors is FALSE?

A. They are one of the most common causes of death in pediatric patients under 20

B. They are more likely to be metastatic tumors in adults

C. The most common location in the CNS for a tumor is intracranial

D. Most adult intracranial tumors are infratentorial

E. Pituitary tumors are common in both adults and children but are not truly considered CNS tumors

Answer 1

D.

Most adult intracranial tumors (ie, GBM, meningioma) are supratentorial, while most child intracranial tumors are infratentorial

Question 2

Most CNS tumors are primary (70%). For the 30% that are metastatic, what is the most common origin?

Answer 2

lung and breast cancers

Question 3

All of the following are common tumor types in children EXCEPT:

A. Meningioma

B. Ependymoma

C. Medulloblastoma

D. Pilocytic blastoma

E. Craniopharyngioma

Answer 3

A. This is more common in adults, as are Astrocytomas (glioblastoma)

*note: ependymomas peak in incidence around age 5 and then again around ages 30-50

Question 4

A high percent this type of cancer metastasizes to the brain

Answer 4

melanoma

Question 5

presenting symptoms of headache, localizing signs, seizures and raised intracranial pressure are relative to supratentorial or infratentorial masses?

Answer 5

supratentorial

*infratentorial masses cause raised ICP as well as cranial nerve defects and cerebellar signs

Question 6

tumors that arise from astrocytes, oligodendrocytes or ependymal cells all fall under the umbrella term “______”.

Answer 6

gliomas

*the most frequent gliomas are astrocytomas

Question 7

Which of the following statements regaring astrocytomas is TRUE?

A. Diffuse astroctyomas are the most common astrocytoma

B. Patients with the 1p/19q deletion oligodendrogliomas have the best prognosis.

C. Patient age, histologic cell type and grade, and preoperative performance status are important in the natural progression of illness, but are not good prognostic factors of gliomas.

D. Pilocytic astrocytoma is the most common astrocytoma in adults

E. Circumscribed variants are much more common than diffuse (infiltrative) variants

Answer 7

B is true - 1p/19q deletion oligos and mutations in IDH1/IDH2 in diffuse gliomas are better prognosis than other kinds.

A is false: Glioblastomas are the most common astrocytoma

C is false: all of these factors are prognostic.

D is false: this is the most common astrocytoma in children

E is false: It is the other way around.

Question 8

Which of the following statements about infiltrating (diffuse) astrocytomas is FALSE?

A. They begin at WHO grade II.

B. They are anaplastic at WHO grade III

C. It is a glioblastoma at WHO grade IV

D. They are non-enhancing on imaging until they reach grade IV

E. Glioblastomas may arise spontaneously or secondarily, but in either case they arise by the same mechanism

Answer 8

E. Primary (spontaneous) glioblastomas arise most often by an EGFR amplification (36%) or PTEN mutation (25%). Secondary GBMs generally arise by a P53 mutation (65%).

Question 9

histopathology of this tumor type shows mildly hypercellular brain parenchyma infiltrated by atypical astrocytes with angular, hyperchromatic nuclei; little to no mitoses.

Answer 9

Astrocytome WHO grade II

*compare to grade III, below, which shows more hypercellularity and is defined by the presence of mitoses:

Question 10

name the ring-enhancing lesion in the image below; what causes the enhancement?

Answer 10

glioblastoma (WHO grade 4); caused by necrosis or vascular proliferation

Question 11

key histopathologic features of this tumor type are pseudopalisading necrosis and vascular proliferation

Answer 11

glioblastoma

Question 12

this WHO grade 1 tumor is the most common type in children and is circumscribed, not infiltrative, arising often in the cerebellum

Answer 12

pilocytic astrocytoma

*note the cystic lesion with enhancing nodule. this is characteristic for pilocytic astrocytoma

Question 13

what tumor cells are depicted in the histological image below?

Answer 13

pilocytic astrocytoma

*has elongated or oval cells with eosinophilic “hair like” processes (Rosenthal fibers, see close up below)

Question 14

this tumor presents with seizures in adults and variable enhancement on imaging; histopathology shows many round hyperchromatic nuclei with perniculear clearing (“halos”), giving it a fried egg appearance:

Answer 14

oligodendroglioma

*like astrocytoma, starts at WHO grade II, but overall people seem to do better with this type than diffuse astrocytomas of the same grade

Question 15

this glial cell tumor is more resectable than others, and tends to occur most commonly in children intraventricularly; but when in adults, it tends to occur supratentorially

Answer 15

ependymoma

Question 16

What key histologic feature is shown below and what type of tumor is this seen in?

Answer 16

pseudorosette clusters, as seen in ependymomas

Question 17

what stain is used to confirm glial cell origin of a neoplasm?

Answer 17

glial fibrillary acidic protein (GFAP)

Question 18

what tumor type is shown below in imaging as an enhancing midline cerebellar mass, commonly in children? what would histopathology show?

Answer 18

Medulloblastoma (WHO IV); histo would show hypercellular small blue neoplasm (below)

Question 19

relatively rare neoplam that arises in teens in the suprasellar region from remnants of Rathke’s puch (embryonic precursor of anterior pituitary); distinct for calicifcations which support diagnosis:

Answer 19

craniopharyngioma (WHO I)

Question 20

presentation of this recurrent tumor type may include visual or endocrine changes, possibly diabetes insipidus

Answer 20

craniopharyngioma

*resembles an adamantinoma (common type of tooth tumor) and has lots of pink calcifications

Question 21

mostly benign enhancing tumor that is common in adults and may cause communicating hydrocephalus

Answer 21

meningioma

Question 22

type of tumor that is usually adherent to the dura, has calcifications called Psammoma bodies, and its cells share eosinohilic cytoplasm

Answer 22

meningioma

Question 23

nearly all primary CNS lymphomas are of this type, which mainly affect the immunocompromised, and have what marker?

Answer 23

B cell lymphomas (CD20)

Question 24

this tumor type shows pleomrophic, hyperchromatic, mitotically active cells that grow around vessels and often cause necrosis:

Answer 24

primary CNS lymphoma

Question 25

systemic lymphomas that metastasize to the CNS as a secondary neoplasm are most often growing where?

Answer 25

on the dura or spreading thru the CSF (leptomeningeal based), as opposed to perivascularly.

Question 26

Which of the following statements is FALSE regarding metastases of malignancies to the brain?

A. They are more common than primary brain tumors in adults.

B. A high percentage of melanomas metastasize to the brain.

C. A single mass will look similar to GBM or an abcess, as a “ring-enhancing lestion”.

D. Metastatic neoplasms often do not infiltrate in a single cell manner, making it possible for them to be scooped out.

E. The most common route of metastases is via the lymphatics.

Answer 26

E. Hematogenous route is most common.

Question 27

the two most common CNS tumor types in children

Answer 27

1: Pilocytic astrocytoma

*tumors in children are usually found below the tentorium

Question 28

the two most common CNS tumor types in adults

Answer 28

1: GBM

*remember that CNS tumors generally grow above the tentorium in adults

Question 29

frequently periventricular in location

Answer 29

primary CNS lymphoma

Question 30

most common types are lung, breast, and melanoma

Answer 30

metastatic tumros

Question 31

most common astroctyic neoplasm

Answer 31

GBM

Question 32

tend to spread via CSF

Answer 32

medulloblastoma

Question 33

benign childhood tumor

Answer 33

pilocytic astrocytoma