Adult Brain Tumors Flashcards
List a few genes and their chromosome aberrations that are risk factors for certain (name them) brain tumors.
Li-Fraumeni Ch. 17- p53- glioma, medulloblastoma
Tuberous Sclerosis Ch. 9/16 - TSC1/2- Subependymal Giant Cell Astrocytoma, Cortical tubers, Glioma
NF1 Ch. 17- Glioma (optic nerve), astrocytoma, glioblastoma
NF2 Ch. 22- Meningioma, schwannoma, ependymoma
MEN Type 1 Ch. 11- Menin- Pituitary
Retinoblastoma Ch. 13- RB1- Retinoblastoma
Von Hippel Lindau Ch. 13- VHL- Hemangioblastoma
What are the most common adult brain tumor types?
Astrocytoma > GBM»> others
Describe the relationship of ICP to cerebral perfusion pressure and their relationship to ischemia.
^ ICP = v CPP = ischemic symptoms
What is the gold standard for Dx of a brain tumor?
How do you get your definitive Dx?
MRI- best for distinguishing tumor from other lesions.
CT- superior for IDing calcifications
DDx- biopsy, except in primary CNS lymphoma (check CSF)
Describe the symptoms you would expect with the following herniation:
Cingulate (downward) herniation
Compression of ACA—> contralateral paresis/paresthesia of legs
Describe the symptoms you would expect with the following herniation:
Diencephalic (downward) herniation
Compression of brainstem–> drowsiness due to compression of reticular formation—> coma, death
Horner’s sign- compression of sympathetic fibers around ICA
Describe the symptoms you would expect with the following herniation: Uncal herniation (downward through tentorium)
Ipsilateral CNIII palsy
Contra/ipsilateral hemiparesis- compression of posterior internal capsule (?)
Describe the symptoms you would expect with the following herniation:
Upward herniation of cerebellum through tentorium
Ipsilateral CNIII palsy
Horner’s syndrome- compression of sympathetic fibers around ICA
Contralateral hemiparesis- compression of posterior internal capsule
Describe the symptoms you would expect with the following herniation:
Cerebellar tonsilar herniation (down towards brain stem)
BP/respiratory insufficiency, weakness, Horner’s syndrome (compression of descending sympathetic fibers in hypothalamospinal tract?- 1st order neuron lesion)
Pt’s got a glioma (astrocytoma, ependymoma, oligodendroglioma). They are old. What is it?
Where is it?
Glioblastoma Multiforme (grade 4 astrocytoma) Cerebral hemisphere
Pt’s got a glioma (astrocytoma, ependymoma, oligodendroglioma). They are young. What is it?
Where is it?
Juvenile pilocystic astrocytoma (grade 1)
Cerebral hemispheres
Pt’s got a glioma. What chemo are you going to give?
Temozolomide + bevacizumab
Why are you going to give a pt w/ a brain tumor steroids?
Restore BBB. Reduce inflammation. Temp. relief of symptoms (not a long term solution)
Why do you give brain tumor pts NON-ENZYME INDUCING anticonvulsants?
Enzyme-inducing AEDs reduce the efficacy of chemo agents as well as contribute to the development of a number of comorbidities, including osteoporosis, sexual dysfunction, and vascular disease.
What functional differences would you expect to see between a micro (
Micro = hypersecretion Macro = mass effect = hyposecretion + compression of other structures (optic chiasm)---> superior field bitemporal (upper outer quad) hemianopsia due to upwards compression (whereas craniopharyngioma ---> inferior field bitemporal (lower outer quad) hemianopsia due to downward compression)
How do we tx pituitary adenomas?
Resection
Octreotide for GH secreting tumors
Bromocriptine/Pergolide for PL secreting tumors
Primary CNS lymphoma is a clonal proliferation of what types of lymphocytes?
What are some RFs for PCNSL
B cells
EBV in immunocompromised pts
What is the MC CNS tumor in AIDS pts?
primary CNS lymphoma
Where are the most common places to find primary CNS lymphoma?
Leptomeninges (Subarachnoid space) and periventricular parenchyma
How do we tx primary CNS lymphoma?
It is a VERY resistant cancer
Tx w MTX, as it crosses the BBB
Steroids
Prog. is still 3-4 yrs for young, otherwise healthy pts
Meningiomas are derived from this type of cell:
Are these tumors considered axial or extra-axial?
Are they usually malignant?
Histology?
Tx?
arachnoid “cap cells” from arachnoid villi
Extra axial bc outside of brain
Usually benign
Look for psammoma bodies on histo (dural tail calcifications on CT)
Observe, resect, radiation
Bilateral acoustic neuromas are associated with what genetic aberration?
How will it present?
NF2 (Ch. 22) inactivating mutation
Hearing loss, tinitis, dizziness, ataxia
List the metastatic cancers to the brain by prevalence.
Lung (50%) Breast Melanoma Colon Renal
How will secondary mets to brain look on CT. Is this specific for mets?
Ring enhancing lesion on T1 MRI. Not specific for mets. Could also be abscess, CVA, high grade glioma, lymphoma, demyelination
