Term
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Definition
1. Glial (intra-axial) - Diffuse astrocytoma, glioblastoma - Oligodendroglioma - Ependymoma - Mixed glioma 2. Meningeal (extra-axial) - Meningioma 3. Neuronal (intra-axial) - Ganglioglioma (temporal lobe) - Central neurocytoma (lateral ventricles) 4. Metastases (intra- of extra-axial) 5. Pituitary adenoma |
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Term
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Definition
1. Pilocystic astrocytoma WHO grade I (cerebellum) 2. Medulloblastoma WHO grade IV (cerebellum) |
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Term
| Brain tumor take home msg |
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Definition
- Common adult primary brain tumors are meningioma, glioblastoma, and pituitary adenoma - Glial/neuronal are intraaxial, meningioma are extraaxial (outisde the brain parenchyma) - Secondary tumors (metastases) are common - Medulloblastoma and pilocytic astrocytoma are common in children |
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Term
| Causes of intracranial mass effect |
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Definition
Intracranial hemorrhage (hypertensive common)
Infection (e.g. abscess)
Tumors
Infarct (with secondary edema)
Edema |
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Term
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Definition
| Normal BBB disrupted. Fluid in extracellular spaces. (around tumor and absecesses) |
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Term
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Definition
| Injury to cells. Fluid in intracellular spaces. E.g. ischemia |
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Term
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Definition
Uncal-medial temporal lobe (uncus) compresses against tentorium cerebelli. CN III and PCA are compressed
Subfalcine-cingulate gyrus under falx. ACA compressed.
External- brain tissue thru dural/skull defect
Tonsillar-cerebellar tonsils thru foramen magnum. Brainstem/respiratory centers compressed. (can kill)
Duret hemorrhages-brainstem herniation causes hemorrhages. often linear and midline in Bst. secondary to tearing of blood vessels |
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Term
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Definition
- Law of 2: NF2, chromosome 22, 2 CP angle schwannomas
- Bilateral CN8 schwannomas diagnostic of NF2
-NF2 gene is Merlin, schwannomin, or neurofibromin 2
- Meningioma, schwannoma, ependymoma can arise in NF2 (occurrence variable)
- Schwannoma is most common (verocay bodies), meningioma (psammoma bodies), ependymoma (perivascular pseudorosettes-cells around a blood vessel)
- Germiline mutations in a tumor suppressor gene predisposes to tumors |
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Term
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Definition
-Most common is meningioma
-Most are benign-slow growing. Even Grade I tumors can recur.
-A subset of sporadic meningiomas will have NF2 mutations |
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Term
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Definition
-Mostly benign Grade I tumors (about 80%)
-Extra-axial (meningeal)
-Histology:whorls, nuclear pseudoinclusions, psammoma bodies
-All grade can recur. Gr III can metastasize
-While NF-2 germline mutations (NF2 syndrome) predisposes to meningiomas, sporadic meningiomas may have somatic NF2 mutations |
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Term
| Intraaxial brain tumors (1ary or 2ary) |
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Definition
-The most common primary intrinsic brian tumor is glioblastoma (a high grade tumor with astrocytic features)
-secondary brain tumors are also common (lung, breast, renal, melanoma, colon) |
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Term
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Definition
- High grade astrocytic tumor
- Median survival: 1 year
- Cancer stem cells (CD133+) present in many gliomas and may drive the tumor |
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Term
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Definition
-Mostly begning Grade I tumors (~80%)
-Extra-axial
-Histology:whorls, nuclear pseudoinclusions, psammoma bodies
-All grades can recur. Gr III can metastasize
-While NF2 germline mutations (NF2 syndrome) predisposes to meningiomas, sporadic meningiomas may have somatic NF2 mutaitons |
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Term
| Biomarkers and targeted therapy |
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Definition
-Similar histologic tumors may evolve different molecular pathways to drive growth and invasion
-MGMG-response to Temodar
-EGFR VIII, PTEN-response to EGFR kinase inhibitors (PI3K/pAKT pathway) |
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