Ward: Cns Tumors

Front 1

What type of stain is required to see the processes of microglial cells?

Back 1

Silver or gold stains
(Invisible in H/E)

Front 2

What type of cell has no known tumors that develop from it?

Back 2

Microglia

Front 3

What does GFAP stand for?

Back 3

Glial Fibrillary Acidic Protein

Front 4

What is GFAP used for?

Back 4

Determining whether a tumor is a primary astrocytic process or it metastasized from another location.
If GFAP +, it is astrocytomatous.

Front 5

What is corpora amylacea?

Back 5

Believed to be an excretory product of astrocytes. No clinical significance.
More common in older people.

Front 6

What are Rosenthal fibers?

Back 6

Protein aggregations that may assume the appearance of streaks or balls.
Protein has certain homology (molecular overlap) with the protein of the lens (of eye). Unknown relation.

Front 7

Where are most (70%) of CNS tumors located in children?
In adults?

Back 7

C: In posterior fossa
A: Supratentorial (hemispheric)

Front 8

What is the ratio of primary to metastatic tumors?

Back 8

50/50 %
Critical!

Front 9

What is the distribution of CNS tumors?

Back 9

Intracranial: 10-17 / 100,000
Intraspinal: 1-2 / 100,000

Front 10

What are the S/S of an astrocytoma?

Back 10

Headache
Focal S/S (depending on anatomical site of involvement)
Seizures

Front 11

Astrocytomas constitute what % of primary brain tumors in adults?

Back 11

80%
Usually hemispheric (but also found in cerebellum, brain stem, spinal cord)

Front 12

At what age do astrocytomas typically present?

Back 12

4th - 6th decades of life.

Front 13

Because it is a space-occupying lesion, what could an astrocytoma cause in the brain?

Back 13

As it continues to expand, it cause herniation d/t increased ICP.

Front 14

What should one think if an astrocytoma is variegaed?

Back 14

Glioblastoma multiforme (Grade IV - worst AC-oma to get)

Front 15

For what reason are astrocytomas notorious?

Back 15

The location is difficult to predict.
Even when "well-demarcated", tumor ALWAYS extends beyond apparent margins!

Front 16

What components are responsible for the colors seen in variegation?

Back 16

Colors generally allude to the effect of necrosis (with necrosis comes hemorrhage, then break down product of hemoglobin catabolism (broken into biliverdin, bilirubin, and hemosiderin – which give the colors). Most of these colors are d/t hemoglobin.

Front 17

Why is the brain asymmetric in an astrocytoma?

Back 17

There is edema d/t neovascularization (new BV are leaky).

Front 18

What can the mass effect of an astrocytoma cause?

Back 18

Uncal herniation
Tonsillar herniation
Kernahan's notch

Front 19

What is a "butterfly glioblastoma"?

Back 19

Glioblastoma involving the corpus callosum

Front 20

At what age does a brain stem glioma typically present?

Back 20

Mostly in first two decades
(These make up 20% of CNS tumors in this age group)

Front 21

To what other CNS problem do brain stem gliomas tend to progress (50% of time, upon autopsy)?

Back 21

GBM = glioblastoma

Front 22

How is a brain stem glioma treated? What is the prognosis?

Back 22

Radiation only (no surgery)
At 5 years: 20-40% (all grades)

Front 23

What are some features of "well-differentiation" of astrocytomas?

Back 23

More variably pleomorphic astrocytes
Intervening feltwork of GFAP+ foot processes

Front 24

What is the histologic grading system used in this course?

Back 24

Simple (3)
1. Low grade
2. Anaplastic
3. Glioblastoma

Front 25

Astrocytomas are anaplastic. What are the 4 features of this?

Back 25

More densely cellular
Greater nuclear pleomorphism
Mitoses
Some endothelial proliferation

Front 26

What is Astrogliosis?

Back 26

Astrocytoma getting into the sub-arachniod space (via pia)

Front 27

What are characteristics of gemistocytic?

Back 27

eosinophilic cell bodies
abundant stout processes

Front 28

What is Gemistocytic?

Back 28

* Gemistocytic = somewhere between grade 2 & 3.
* Is a fairly aggressive astrocytoma

Front 29

Describe the histology of Glioblastoma multiforme.

Back 29

Same as anaplastic, but with:
* Serpentne necrosis and palisading
* Increased formation of VEGF with major endothelial proliferation and formation of "glomeruloid" bodies.

Front 30

What does VEGF stand for?

Back 30

Vascular endothelial growth factor

Front 31

What is the purpose/function of VEGF?

Back 31

It is a cytokine made by endothelial cells and tumor cells
It makes tumors grow and has an effect of their blood vessels.

Front 32

When there's a lot of VEGF around capillaries, what structure do they resemble?

Back 32

Glomeruli (from kidney)

Front 33

What does necrosis look like histologically?

Back 33

Pink, amorphous, no nuclei

Front 34

What is a quick/dirty way to Dx astrocytoma?

Back 34

Frozen section. Take material from biopsy, place it between two slides and pulls them apart.

Front 35

What is the prognosis of well-differentiated astrocytoma?

Back 35

Progress slowly or stay the same.
Most become anaplastic.

Front 36

What constitutes Triple Treatment?

Back 36

Chemo, Radiation, Surgery (any order)

Front 37

What is the prognosis of Glioblastoma?

Back 37

Mean = 10 months.
< 10% alive at 2 years.

Front 38

What are the molecular aspects of low grade astrocytoma?

Back 38

Inactivation of p53
Overexpression of PDGF-A and its receptor

Front 39

What are the molecular aspects of the transition to high grade astrocytoma?

Back 39

Disruption of:
* RB gene
* p16/CDKNZA gene
* 19q gene

Front 40

What are the molecular aspects of secondary glioblastoma?
(Low to high grade already)

Back 40

Mutation of p53

Front 41

What are the molecular aspects in older patients with short clinical history?

Back 41

Amplification of EGF(R)

Front 42

What are the molecular aspects of Adult de novo?

Back 42

No known gene abnormalities

Front 43

In which age group do pilocytic astrocytomas occurs?

Back 43

In children and young adults

Front 44

Where in the CNS do pilocytic astrocytomas occur?

Back 44

Cerebellum > 3rd ventricle, optic nerves, hemispheres

Front 45

What are some characteristics of Pilocytic astrocytomas?

Back 45

* Often cystic with mural nodules
* Behave like hamartomas (this begets up to 40 year survival)

Front 46

Microscopically, what constitues the loose tissue of Pilocytic astrocytomas?
The dense?

Back 46

loose: bipolar cells with GFAP(+) “hairs”
dense: Rosenthal fibers

Front 47

What are the 3 types of tumors lumped together as "glioma"?

Back 47

Astrocytoma
Oligodendroglioma
Appendymoma

Front 48

What is the typical S/S of oligodendroglioma?
(Make up 5-15% of gliomas)

Back 48

Seizures

Front 49

When do Oligodendroglioma typically present?

Back 49

4th or 5th decade

Front 50

What is the prognosis for Oligodendroglioma (with triple Rx)?

Back 50

5-10 years

Front 51

How do Oligodendroglioma appear grossly?

Back 51

Mostly in white matter of hemispheres
Sharply circumscribed
Grey, Gelatinous
May or may not have cysts or hemorrhages

Front 52

How do Oligodendroglioma appear microscopically?

Back 52

Cells have round nuclei and cytoplasmic halos.
There's a delicate network of capillaries.
Calcification in 90% (dystrophic type)

Front 53

What does metabolic calcification require?

Back 53

Hypercalcemia

Front 54

Where are the codeletion of Oligodendroglioma located?

Back 54

1p, 19q
(Occurs in 50-80% of cases)

Front 55

What do these genetic characteristics mean for the patient?

Back 55

Prolonged survival
Favorable response to chemo/rad

Front 56

Where are ependymoma typically located in children?
In adults?

Back 56

Near 4th ventricle
In cord (myxopapillary)

Front 57

In children, what does ependymoma usually manifest as?

Back 57

Hydrocephalus
(Why? Obstruction of lower aqueducts (thus non-communication HC) - CSF cannot get out)

Front 58

What is the prognosis of ependymoma in children?

Back 58

Poor, slow growing.
Survival = 4 years post Tx (surgery, rad)

Front 59

Why is CSF dissemination common in ependymoma?

Back 59

Because likely to be exfoliatory (as it arises from ependyma) - thus more likely to get out into CSF.

Front 60

What do ependymomas look like grossly?

Back 60

Solid/papillary masses - floor of 4th ventricle.
More demarcated than astrocytomas

Front 61

When can an ependymoma be extirpated (surgically removed)?
When can't it?

Back 61

Can: when in spinal cord
Can't: when close to vital centers

Front 62

What are some microscopic characteristics for ependymoma?

Back 62

GFAP+ (50%)
Round/oval nuclei
Dense Fibrillary background
Canals, pseudorosettes, rosettes

Front 63

When a canal is seen in ependymoma, what is it trying to create?

Back 63

Small ventricles (lined by ependymal cells

Front 64

What is lacking in a true rosette?

Back 64

A lumen

Front 65

What structure does myxopapillary ependymoma involve?

Back 65

Filum terminale

Front 66

What degenerates in myxopapillary ependymoma?

Back 66

Mucin / myxoid

Front 67

What does myxoid mean?

Back 67

Gelantinous

Front 68

Why are myxopapillary ependymoma amenable to surgery?
What is a possible complication of the surgery?

Back 68

Because it is peripheral (no vital centers around)
Localized Paralysis (not fatal)

Front 69

With any sort of papillary object, what is also present and why?

Back 69

Vascular core
Need to sustain life

Front 70

In which age group are medulloblastoma typically found?

Back 70

Children

Front 71

In which structure are medulloblastoma found?

Back 71

Cerebellum (exclusively)
Midling in children

Front 72

What kind of hydrocephalus can medulloblastoma produce?

Back 72

Obstructive (non-communicating)

Front 73

How does medulloblastoma get into the SAS?

Back 73

Seeding
"Drop" Metastases

Front 74

What is the best treatment for medulloblastoma?

Back 74

Radiation therapy
(+ surgery = 75% 5 year survival)
* Without Tx, Px is dismal

Front 75

Describe gross features of medulloblastoma.

Back 75

Well-circumscribed, grey, friable tumor; may involve meninges (seeding)

Front 76

Describe microscopic features of medulloblastoma.

Back 76

* Sheets of small, dark anaplastic cells
*Cells are elongated/crescentic
* Lots of mitoses
* Homer-Wright rosettes
* Neuronal or glial markers (thus, the tumor is a hybrid)

Front 77

What is the genetic component of medulloblastoma?

Back 77

i(17q)
i = isochromasome (part of chr is turned upside down)

Front 78

What are the two disease processes that are candidates for seeding?

Back 78

medulloblastoma, ependymoma
(more likely in MB - often seed interventricularly)

Front 79

Where else are Homer-Wright rosettes seens?

Back 79

In tumor of adrenals - "neuroblastoma"

Front 80

What is present inside rosettes that have neuronal parentage?

Back 80

Fibrils that are "neurophil"

Front 81

A tumor with which characteristic is highly amenable to chemo/rad?

Back 81

Lots of mitotic activity

Front 82

What is the most common CNS tumor in immunosuppressed patients?

Back 82

Non-Hodgkin Lymphoma (NHL)
(but accounts for 1% of all primary tumors)

Front 83

Where do cells congregate in NHL?

Back 83

* Are easily detectable in CSF
* Cluster around nerve roots

Front 84

What is rare in NHL?

Back 84

Extracranial extension
(Note: Brain is involved in only 2% of extranodal NHLs)

Front 85

What cells make up the majority of primary brain lymphomas?

Back 85

B-cells

Front 86

What virus is present in all transformed B-cells (in immunocompromised patients)?

Back 86

EBV (not necessarily causative, may be a passenger or epi-phenom)

Front 87

What is the progression / prognosis of primary brain lymphomata?

Back 87

Agressive, large-cell NHL
Poor response to chemo

Front 88

What sets CNS tumors apart from tumors found elsewhere?

Back 88

* Less distinction btw benign and malignant lesions
* Limited ability to surgically remove neoplasms without compromising neurological functions.
* Anatomical site of tumor can have lethal consequences, no matter what the histology.
* Different pattern of spread (even very malignant tumors rarely spread outside the CNS)

Front 89

What provides a pathways for spread of tumors?

Back 89

Subarachnoid space

Front 90

What are the four classes of brain tumors?

Back 90

1. Gliomas
2. Neuronal tumors
3. Poorly differentiated neoplasms
4. Meningiomas