Module 7:CNS: Brain Tumors

Question 1

This card deck will focus on the last topic of brain tumors. First are primary brain tumors, what are intrinsic vs extrinsic and supratentorial vs infratentorial?

Answer 1

Intrinsic: gliomas (astrocytic, oligodendroglial)
Extrinsic: meningiomas, schwannomas
Supratentorial in adults
Infratentorial in children

Question 2

Secondary brain tumors are considered metastases, which is the most common brain tumor. What are the most common sources of these mets?

Answer 2

1. Small cell lung cancer

2. Breast ( her 2 positive and triple negative)

Question 3

What will the CT scan show for mets to the brain?

Answer 3

Multiple ring enhancing lesions in the cerebral hemisphere

Question 4

Lymphoma is another common metastases to the brain, from what?

Answer 4

Esp in immunocompromised /HIV patients

–associated with multiple sexual partners

Question 5

The first primary brain tumor to discuss is Glioblastoma Multiformes, what is the pathogenesis?

Answer 5

Most aggressive malignant tumor in the brain

• -origin = glial cells/astrocytes
• -high grade astrocytoma (Space occupying lesion) That spreads from one hemisphere (White matter) to the next through the corpus callosum

Question 6

What is seen on gross and histology for a Glioblastoma Multiformes?

Answer 6

Butterfly appearance on gross
Located in the cerebral hemisphere (cross over at the corpus callosum)
Very hemorrhagic and necrotic
Histology: central area of necrosis surrounded by pseudo-pallacading of the malignant cells

Question 7

What is the presentation for a Glioblastoma Multiformes?

Answer 7

Found in adults (40-60 yr olds)
–supratentorial
Sudden Onset
Recurrent headaches (Worse in the AM and while straining), seizures, papilledema, contralateral hemiparesis and projectile vomiting

Question 8

What is the tumor marker for Glioblastoma Multiformes?

Answer 8

GFAP tumor marker (glial fibrillary acidic protein)

Question 9

What is a poor prognosis for Glioblastoma Multiformes?

Answer 9

Infiltrate
Unresectable
Resistant to treatment

Question 10

What is a better prognosis for Glioblastoma Multiformes?

Answer 10

Younger 
-EGFR
\+IDH-1
\+p53
\+MGMT methylation

Question 11

What is the overall prognosis for patients with Glioblastoma Multiformes?

Answer 11

High grade astrocytoma (so patient dont live very long maybe a year)

Question 12

The next brain tumor is an Oligodendroglioma, what kind of tumor is that?

Answer 12

Well differentiated glioma in 3rd and 4th decade

–indolent course and often calcified

Question 13

What is the etiology for Oligodendroglioma?

Answer 13

Loss of heterozygosity for ch 1 & 19

Question 14

What is the prognosis for Oligodendroglioma?

Answer 14

Good prognosis b/c chemosensitive

–better prognosis if 1p and/or 19q deletions

Question 15

The next brain tumor is a Meningioma, what is the etiology?

Answer 15

Benign tumor with Benign Behaviors (slow growing and well circumscribed)

• mostly sporadic and in older patients over 40
• -if familial: associated with neurofibromatosis II NF2 (also associated with this is vestibuloschwannoma + meningioma)
• -common in black women

Question 16

What is the pathogenesis for a Meningioma?

Answer 16

Dome shaped tumor of the meningothelial cells of the arachnoid attached to the underside of the dura

Question 17

What are the signs and symptoms of a Meningoma?

Answer 17

Gradual onset
Headaches, Projectile vomiting and papillemdema
Seizures (irritates the cerebral cortex)

Question 18

What is seen on CT and excisional biopsy (Best investigation) for a patient with a meningoma?

Answer 18

See calcifications on CT: psammoma bodies

Excisional Biopsy: papillary projection (Whorled pattern of cell growth) with psammoma bodies

Question 19

What are the complications associated with a meningioma?

Answer 19

Complications: Compression of the cerebellar hemisphere — focal neuro deficits, cranial nerve problems and seizures
High degree of recurrence after removal but good prognosis

Question 20

There are two types of Nerve Sheath Tumors, neurofibroma and schwannoma. What are some features of a schwannoma?

Answer 20

Middle aged and elderly (earlier in NF2)

Slow growing tumor that arises from Schwann Cells

Question 21

Schwannoma most commonly affects, what?

Answer 21

CNVIII: acoustic neuroma

Spinal Sensory nerve roots

Question 22

Nerve sheath tumors are cured by what?

Answer 22

Resection (Risk to perent nerve function)

Question 23

The next brain tumor is seen in kids called a Pilocytic Astrocytoma, what are some features?

Answer 23

Most common primary CNS tumor in childhood
–well differentiated glioma in the cerebellum & hypothalamus (composed of compactly and loosely arranged delicate hair like astrocytes)

Question 24

What is seen on CT/MRI in a patient with a pilocytic astrocytoma?

Answer 24

Cystic with enhancing rim and mural nodule

Question 25

How is pilocytic astrocytoma cured?

Answer 25

Resection

Question 26

The last brain tumor for this section is a Medulloblastoma, who is this seen in and what is the origin?

Answer 26

Seen in Children
–intratentorial
Origin: Cerebellar Vermis (can co-exist with Ewings tumor)

Question 27

What is seen on presentation for patients with Medulloblastoma?

Answer 27

Cerebellar Signs (ataxia, slurred speech, intention tremor, nystagmus, 3Ds)

Question 28

What is seen on histology for a medulloblastoma?

Answer 28

Excisional Biopsy (Best investigation): 
--homer-wright rosettes (pseudorosettes) - small round blue cells

Question 29

What are the complications of a Medulloblastoma?

Answer 29

Malignant tumor — spreads via CSF — spreads to ventricles – hydrocephalus (obstructive or non communicating)
Drop Metastasis: tumor cells detach, enter ventricles (Can reach cauda equina — cauda equina syndrome and nerve pain)

Question 30

What is the prognosis for a Medulloblastoma?

Answer 30

Radiosensitive
-risk of papillary thyroid cancer
Beta-Catenin positive so good prognosis

Question 31

If Medulloblastoma is familial what diseases is it associated with?

Answer 31

Tuckers

Ghorlin