Tumors of the CNS

Question 1

Most frequent primary tumor of the CNS

Answer 1

Infiltrative astrocytoma

Question 2

Risk factors for CNS tumors

Answer 2

• ionizing radiation
• immunosuppresion
• genetic syndromes

Question 3

Do we need to know all of these hereditary syndromes assoc with brain cancer?

Answer 3

ask

Question 4

Cerebreal perfusion pressure is the difference between

Answer 4

MAP and intracranial pressure. Intracranial pressure remains fairly constant until the brain compliance threshold is reached. Then small increases in the size of a tumor can lead to large increases in intracranial pressure and thus drive down cerebral perfusion

Question 5

General signs and symptoms of CNS tumors

Answer 5

headache
vomitting
mental status change

Question 6

Focal signs and symptoms

Answer 6

papilledema
Seizures
focal neuro deficits

Question 7

Stop at 17

Answer 7

ok

Question 8

Subfalcine herniation

Answer 8

herniation of the cingulate gyrus under the falx cerebri.

May compress anterior cerebral artery and CVA

Question 9

Diencephalic downward herniation

Answer 9

• may cause drowsiness, impaired vertical gaze or small pupils bilaterally

Question 10

Uncal herniation

Answer 10

ipsilateral oculomotor nerve palsy and contra or ipsilateral hemiparesis

Question 11

Upward herniation through tentorium

Answer 11

may cause ipsilateral oculomotor, horner, and contralateral hemiparesis

Question 12

Tonsilar herniation

Answer 12

causes BP changes, weakness, respiratory disturbance, horner syndrome

Question 13

T1 weighted MRI scan

Answer 13

Water is hypointense (dark); ie tumor, swelling, CSF darker than surrounding brain

Injected contrast that leaks across the disrupted BBB appears hyperintense with an increased signal or brighter than the surrounding brain.

Question 14

T2 weighted MRI scan

Answer 14

CSF Edema and tumors appear hyperintense.

Question 15

What does Glioma mean?

Answer 15

tumor derived from glial cells

Question 16

Most common primary CNS tumors are gliomas, of glial origin

Answer 16

know

Question 17

Low grade tumors most commonly seen in

Answer 17

younger population

Question 18

High Grade Tumors more commonly seen in

Answer 18

those older than 50

Question 19

Low grade tumor characteristics

Answer 19

well differentiated, show no nuclear atypia, and have low mitotic index.

Question 20

Increasing de-differentiation, higher mitotic index, vascular proliferation, and necrosis determine higher tumor grade.

Answer 20

Know

Question 21

How many tumor grades are there

Answer 21

4

Question 22

radiation modalities

Answer 22

• conventional: no longer used
• conformal: tumor gets more dose while normal brain dose is reduced
• radiosurgery: high dose of conformal radiation given in a single fraction
• brachytherapy: insertion of radioactive material in tumor cavity

Question 23

What is bad about conventional radiation

Answer 23

tumor tissue and normal tissue receive the same dose

Question 24

Meningioma

Answer 24

outside of the brain (extra-axial) tumors characterized on MRI by diffuse enhancement and a DURAL TAIL.

Generally benign and resectable

May show seizures or focal signs due to brainstem compression. Remember that it is the second most common primary brain tumor

Question 25

3rd most common primary brain tumor

Answer 25

Pituitary tumors

Question 26

Classifications of pituitary tumors

Answer 26

• Microadenomas: most often hrmone secreting
• Macroadenomas: most often do not secrete hormones, often grow large enough to cause sompression and hypofunction of gland or pituitary stalkP

Question 27

Pituitary tumors often compress what?

Answer 27

Optic chiasm

Question 28

Acoustic neuroma also called

Answer 28

vestibular schwannoma- benign tumor of schwann cells surrounding CN VIII

• Benign slow growing tumors that often present with hearing loss, tinnitus, headache, dizziness, facial numbness or weakness
• treatment= observation, surgical excision, excellent outcome with experienced neurosurgeon

Question 29

Primary CNS lymphoma

Answer 29

on the rise, due to malignant transformation on trafficking B lymphocytes. Highly chemo and radiosensitive tumor.

Question 30

Most common brain neoplasm is really mets

Answer 30

most common sites for tumors to met from is Lung, breast, melanoma, colon