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Flashcards in Neuro - Tumors Deck (51)
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1
Q

How would glioblastoma multiforme present histologically?

A

Marked cellularity with pleomorphic, hyperchromatic, anaplastic cells.
Prominent areas of necrosis are seen with pseudopalisading tumors cells surrounding them

2
Q

What type of tumor (cell type) is glioblastoma multiforme?

A

a glial tumor

grade IV astrocytoma

3
Q

If a patient presents with a 5-year history of neurological symptoms, and a tumor is suspected, why would you or wouldn’t you suspect glioblastoma multiforme?

A

It would be unlikely for this patient to have glioblastoma multiforme because of the long duration of symptoms. Glioblastoma is a highly malignant brain tumore with an approximately 1 year median survival. This tumor is aggressive and would likely kill the patient before 5 years have passed.

4
Q

Anatomically, where and how does glioblastoma multiforme present?

A

in the cerebral hemispheres; it can cross the corpus callosum: “butterfly glioma”

5
Q

What would cells in glioblastoma multiforme stain positive for?

A

GFAP (glial fibrillary acidic protein)

6
Q

A five-year history of neurologic symptoms, seizures, headaches, bilateral leg weakness, hyperostosis and a whirling pattern of cells on histology. What is the likely diagnosis?

A

Meningioma.

Meningiomas often occur in the convexities of the the hemispheres of the brain and the parasagittal region. The symptoms they cause are due to mass effect; the bilateral leg weakness in this scenario would be due to compression of the precentral gyrus due to a meningioma being located in the parasagittal region.

7
Q

What is the classic histology of a meningioma?

A

*spindle cells arragned in a whorling pattern.

psammoma bodies (a round collection of calcium, seen microscopically)

8
Q

From what cells does a meningioma arise?

A

From arachnoid cells. This tumor is outside the brain parenchyma.

9
Q

How do metastatic tumors usually present?

A

Lesions that are:

  • -multiple
  • -round
  • -well-circumscribed
  • -at the white-gray junction
10
Q

How can a meningioma present?

A

This tumor compresses the underlying cortex, causing symptoms via mass-effect.

It may present with seizure, or focal neurologic deficits

11
Q

From what cell do schwannomas arise?

A

schwann cells (peripheral nerves)

12
Q

Where do schwannomas typically present?

A

Most frequently involves CN VIII at the cerebellopontine angle

(this is also called an acoustic schwannoma, aka, acoustic neuroma)

13
Q

For what protein are schwannomas positive?

A

S-100

14
Q

In what disease are bilateral acoustic schwannomas found>

A

Neurofibromatosis type 2 (NF-2)

15
Q

Is glioblastoma multiforme benign or malignant?

A

malignant

16
Q

Is meningioma benign or malignant?

A

benign

17
Q

Is schwannoma benign or malignant?

A

benign

18
Q

Is oligodendroglioma benign or malignant?

A

malignant

19
Q

What is the classic histological presentation of oligodendrogliomas?

A

round nuclei with clear cytoplasm, giving a “fried egg” appearance

20
Q

Where are oligodenrogliomas usually present?

A

In the frontal lobes

21
Q

How might an oliodenroglioma present?

A

May present with seizures or focal deficits (similar to meningiomas)

An oliodendroglioma can be differentiated from a meningioma based upon histology. Also, oligodendrogliomas do not cause hyperostosis of the calverium, whereas meningiomas often do

22
Q

Common presentation of a pituitary adenoma?

A

Bitemporal hemianopia due to compression of the optic chiasm.

This can be described in a case scenario as “reduced peripheral vision”

23
Q

What might be a common second symptom of a person presenting with bitemporal hemianopia due to a pituitary adenoma?

A

Galactorrhea (spontaneous flow of milk from the breast).

This is because the most common type of pituitary adenoma is a prolactinoma, which would secrete increased amounts of prolactin. Prolactin stimulates the breast to produce milk.

24
Q

What are common adult primary brain tumors?

A

(1) glioblastoma multiforme
(2) meningioma
(3) schwannoma
(4) hemangioblastoma
(5) oligodendroglioma
(6) pituitary adenoma

25
Q

From what cell type does a medulloblastoma arise?

A

Characterized by both glial and neuronal differentiation.

This is unique to medulloblastomas

26
Q

Where do medulloblastomas typically arise (anatomically)?

A

In the cerebellar vermis.

27
Q

What are the consequences of the location in which medulloblastomas arise?

A

Because they arise in the cerebellar vermis, this accounts for the cerebellar symptoms that can be present (ataxia).

Because of this location, these tumors can also compress the fourth ventricle, causing non-communication hydrocephalus

28
Q

What would we see on histology with a medulloblastoma?

A

Homer-Wright rosettes.

sheets of densely-packed, poorly differentiated, small, blue cells.

29
Q

What are Homer-Wright rosettes?

A

A halo of tumor cells surrounding a central region containing neuropil.

30
Q

Are medulloblastomas benign or malignant?

A

malignant

31
Q

What protein can a medulloblastoma stain positive for?

A

GFAP (glial fibrillary acidic protein)

32
Q

What is a feared progression of medulloblastoma?

A

The tumor can enter the 4th ventricle and spread via the CSF. Metastases can then travel to the spinal cord and the cauda equina. These are called “drop metastases”

33
Q

Where are ependymomas commonly found?

A

In the fourth ventricle.

34
Q

What complication/symptom results from the common location of ependymomas?

A

Because they are found in the 4th ventricle, they can obstruct the flow of CSF and cause non-communicating hydrocephalus.

35
Q

What is a characteristic finding of ependymomas on biopsy/histology?

A

Perivascular rosettes.

36
Q

Are ependymomas benign or malignant?

A

Malignant

37
Q

What tumor can be confused with a pituitary adenoma, as it also causes bitemporal hemianopia?

A

craniopharyngeoma

38
Q

From what structure are craniopharyngeomas derived?

A

Derived from remnants of Rathke’s pouch

39
Q

What is commonly seen on imaging with craniopharyngeomas that would differentiate it from a pituitary adenoma?

A

Calcifications.

These are common in craniopharyngeomas; as they are derived from “tooth-like” tissue from the floor of the mouth.

40
Q

Are craniopharyngeomas benign or malignant?

A

benign

41
Q

Where are pilocytic astrocytomas most often found?

A

In the posterior fossa (e.g., the cerebellum)

42
Q

What would imaging show with a pilocytic astrocytoma?

A

A cystic lesion with a mural nodule (a nodule growing on its wall)

43
Q

What protein would pilocytic astrocytomas stain positive for?

A

GFAP (glial fibrillary acidic protein)

44
Q

From what type of cell are pilocytic astrocytomas derived?

A

glial cells

45
Q

What would we see on histology with a pilocytic astrocytoma?

A

Rosenthal fibers: eosinophilic, corkscrew fibers

46
Q

Are pilocytic astrocytomas benign or malignant?

A

benign

47
Q

What are the common childhood primary tumors?

A

(1) pilocytic astrocytoma
(2) medulloblastoma
(3) Ependymoma
(4) craniopharyngeoma

48
Q

What tumors tend to metastasize to the brain? (5)

A

(1) lung
(2) breast
(3) kidney
(4) colorectal
(5) melanoma

49
Q

What tumors in children are known to occupy/compress the 4th ventricle, leading to hydrocephalus?

A

Medulloblastoma and ependymoma

50
Q

How would you differentiate between an ependymoma and a medulloblastoma?

A

Histologically:

  • -Medulloblastomas are neuroectodermal tumors that have glial and neuronal differentiation. They would be GFAP (+)
  • -Medulloblastomas classically have Homer-Wright rosettes, whereas ependymomas characteristically have pervascular rosettes
  • -the medulloblastoma tumor consists of sheets of densely-packed, poorly differentiated small blue cells
51
Q

Symptoms of a parasagittal meningioma

A
  • -headache
  • -spastic paresis
  • -urinary incontinence