243b CNS tumors

Question 1

what occurs more often in CNS tumors - primary or secondary?

Answer 1

secondary - metastasize from elsewhere to CNS

lung, breast, melanoma

Question 2

CNS general symptoms vs localized

Answer 2

general = headaches, seizures, personality change

localized = weakness, sensory, gait ataxia, visual/language changes

headache is rarely sole presenting symptom of CNS tumor

Question 3

dx of CNS tumors

Answer 3

MRI w/ and w/out contrast

histological dx requires tissue sample

Question 4

Glioblastoma multiforme (grade IV astrocytoma)

Answer 4

Common, highly malignant 1° brain tumor with ~1-year median survival.

astrocyte origins

Found in cerebral hemispheres. Can cross corpus callosum (“butterfly glioma”). Stain astrocytes for GFAP.

“Pseudopalisading” pleomorphic tumor cells - border central areas of necrosis and hemorrhage.

Rx - surgery (as much as possible) –> chemo (temozolomide) + radiation

Question 5

Gliomas - origin

Answer 5

neuro-epithelial tissue

glial = 90% of cells in CNS

Question 6

recurrent GBM rx

Answer 6

chemo impregnated wafers

anti-angiogenic therapy –> delays wound healing

immunotherapy: passive (exogenous Ab targets antigen on cancer cells, t-cells) and active (immunizing patient against tumor cells, creates memory response)

HSP - heat shock proteins; isolate peptide complexes –> peptide chaperones; can use as a vaccine –> activate B and T cells to attack cancer cells

Question 7

Schwannoma (first aid)

Answer 7

Usually found at cerebellopontine angle.

Schwann cell origin, S-100; often localized to CN VIII –> acoustic schwannoma (aka acoustic neuroma). Resectable or treated with stereotactic radiosurgery.

Bilateral acoustic schwannomas found in NF-2.

Question 8

Meningioma (first aid)

Answer 8

Common, typically benign 1° brain tumor.

Most often occurs in convexities of hemispheres (near surfaces of brain) and parasagittal region.

Arises from arachnoid cells, is extra-axial (external to brain parenchyma), and may have a dural attachment (“tail”).

Often asymptomatic; may present with seizures or focal neurological signs.

Resection and/or radiosurgery.

Spindle cells concentrically arranged in a whorled pattern; psammoma bodies (laminated
calcifications).