Chapter 28: CNS Tumors

Question 1

Which are more common, primary CNS tumors or metastatic tumors in the CNS?

Answer 1

Metastatic by far

Especially from the lung

Also breast, melanoma, kidney and GI

Question 2

A 30 y/o male with AIDS presents with neurological symptoms. You get an MRI and find a brain tumor.

Based on the PMH, what type of primary CNS tumor is this most likely to be?

What cell marker will it most likely express?

How will you treat it, at least at first?

Answer 2

Primary CNS lymphoma (most likely B-cell)

CD20

Initially respond well to steroids

*Immunocompromised, or old people, CD20*

Question 3

A 28 y/o female presents with headaches. You find elevated EPO when you run blood tests.

Polycythemia, duh.

UMM…this is the brain chapter, so now I’m going to tell you that your MRI shows a cyst with a mural nodule in the cerebellum (Oh yea, she was also ataxic)

Also forgot to mention Von-Hippel Lindau runs in the fam

What’s she got?

Answer 3

Hemangioblastoma

*Cerebellum, von-Hippel Lindau, secondary polycythemia, inhibin-alpha immunostaining*

Question 4

Your name is Dr. McDreamy. Aside from being insanely gorgeous, you also are a talented neurosurgeon. A patient comes to you because they want their ependymoma taken out.

Where is the most likely location for this tumor?

What commonly develops due to this location?

Answer 4

Fourth ventricle

Hydrocephalus

*Usually kids/young adults, ventricles (esp 4th) hydrocephalus, perivascular pseudorosette, EMA and GFAP positive*

(Ependyma cells line the ventricles, so these tumors are all in the ventricles)

Subtype: myxopapillary ependymoma=lower part of spinal cord of young adults, conus medullaris

Question 5

Your patient presents with bitemporal hemianopia and polyuria/polydipsia. You immediately think pituitary adenoma.

BUT WAIT! Your patient is only 10! What is this more likely to be?

Answer 5

Craniopharyngioma

Tumor in the sella turcica

*Bitemporal hemianopia, kids, Rathke cleft*

Question 6

What epithelial remnants are craniopharyngiomas derived from?

Answer 6

Rathke cleft

Question 7

A 7 y/o boy comes to your office because his mom says he’s “walking funny.” He also can’t bring his heel down his shin when you ask.

Suspecting a tumor, you send him to get an MRI and subsequent biopsy, which comes back looking like the picture. What does he have?

Answer 7

Medulloblastoma

*Cerebellum, kids, neuroblastic rosettes, small blue cells, can fill 4th ventricle and spread thru CSF to spinal card*

Question 8

What embryological tissue are medulloblastomas derived from?

Answer 8

Neuroectoderm

Question 9

Your patient’s pathology comes back with this:

(Hint: tumor cells around blood vessels)

What’s this called? What do they have?

Answer 9

Perivascular pseudorosettes

Ependymoma

Question 10

Where do oligodendrogliomas commonly occur?

What symptoms do they present with?

What food do their cells look like?

Answer 10

White matter of cerebral hemispheres

Seizures

Fried egg/perinuclear halo

*Above, plus commonly adults in 40s/50s, calcification on MRI*

Question 11

What do all glial cell tumors (astrocytomas, oligodendrogliomas, ependymomas etc) stain positively for?

Answer 11

GFAP

Glial fibrillary acidic protein, a type of intermediate filament

Question 12

I say Rosenthal fibers, you say…..

Answer 12

PILOCYTIC ASTROCYTOMA!

Question 13

Your 5 y/o pt has a brain tumor that doesn’t infiltrate the brain, and shows a contrast enhancing cystic lesion on MRI. What do they have?

Answer 13

Pilocytic astrocytoma

*kids, non-infiltrative, contrast enhancing (due to vascular proliferation), cystic with mural nodule, Rosenthal fibers*

Question 14

What is the most malignant type of astrocytic tumor?

Answer 14

Gliobastoma multiforme

Question 15

A 65 y/o man comes in with horrible headaches. You do an MRI and find a tumor that crosses between both hemispheres.

What’s the most likely diagnosis based on that fact alone?

Answer 15

Glioblastoma multiforme

Question 16

What are some glioblastoma buzzwords?

Answer 16

Diffuse astrocytoma, “butterfly” because they can cross hemispheres via corpus callosum

Ring-enhancing lesion with central necrosis, necrosis surrounded by cuff of tumor cells=pseudopalisading necrosis

Question 17

What types of tumors does neurofibromatosis type 2 (NF-2) predispose you to?

Answer 17

Meningiomas, gliomas, and schwannomas/acoustic neuromas

Question 18

Ms. Spider is a 53 y/o who has been having recurrent seizures and lost her sense of smell. You’re thinking tumor and get imaging studies.

You find the tumor, but also a lytic bone lesion. What is this?

Where is this tumor derived from?

Answer 18

Meningioma

Arachinoid cells (get it?! Ms. Spider, ha ha)

*females, seizure, found in locations of arachinoid membrane/meninges, whorled pattern on histology with psammoma bodies, non-infiltrative*

Question 19

What brain tumor is associated with this pathology?

Answer 19

Meningioma

Whorled pattern with psammoma bodies

Question 20

Who are more likely to have infratentorial tumors (below the tentorium cerebelli)?

Answer 20

Kids

Adults are much more likely to have supratentorial tumors (aka not the cerebellum or 4th ventricle)