CNS Neoplasms Flashcards
Astrocyte neoplasms grading (which are most common)
- diffuse = grade II
- Anaplastic = grade III
- glioblastoma = grade IV
Diffuse and glioblastomas account for 80% of primary brain tumors
CNS tumor epidemiology
- low incidence except in childhood (20% of childhood cancers are CNS tumors)
- rarely metastasize outside the CNS
Anaplastic transformation
Astrocytes mutation - p53 mut/ gain chrom 7, loss of hetero 17p
Astrocytoma - chrom 19q loss/ Rb gene mutation, p16 homo deletion
Anaplastic astrocytoma - chrom 10q: EGFR amplification and PTEN mutation
Diffuse astrocytoma: macro
Diffuse expansion of white matter
Poorly demarcated
Brain stem or thalamus
Spinal cord association with syrinx
Glioblastoma on CT
Ring of enhancement surrounding necrosis
- often butterfly lesion: spanning corpus callosum
- palisading necrosis or vascular proliferation
GBM prognosis
- mean survival = 12 mo (younger PTs. Better prognosis)
- brain stem glioblastoma difficult t rescect -> poor prognosis
Pilocytic astrocytoma: morphology, characteristics, prognosis
Only grade 1 we talk about
- well circumscribed
- common in younger
- rarely progressive
- usually in places other neoplasms avoid
- better prognosis (cyst is good)
Rosenthal fibers
Associated with pilocytic astrocytoma
Oligodendrogliomas presentation and history
- frontal lobe, typically associated with calcification
- adult tumors
- history includes seizures
- loss of 19q and 1p
- chemosensitive
Histo oligodendroglioma and prognosis
Perinuclear halo: fried egg
- loss of both chromosome increases prognosis
Ependymoma
Intercranial: children (typically lateral ventrical)
Spinal: adults
- loss of chrom 22
- normal grading: myxopapillary ependymoma = grade I
- perivascular pseudorossets (may have true rosettes)
Myxopapillary ependymoma: location, association
Grade I ependymoma
- conus medullaris, filum terminale
- associated with syringomyelia
Embryonal neuroepithelial neoplasm: locations, prognosis factors, characteristics
- PNET (primitive neuroectodermal tumor) highly malignant
- generally cerebellar: children vermis, adults lateral
- CSF dessimination common
- increased TrKC = better prognosis
- blue = bad, Homer-Wright rosettes
Primary CNS lymphoma: epi, trt
- most are large B cell lymphomas
- 6th-7th decade for immunocompetant
- 4th decade for immunocompromised
- responds to roids and methotrexate
- tumor cells around blood vessels
Schwannoma
Slowly growing neoplasm
Acousting neuroma (CN VIII) bilateral NF-1
4th-6th decade
Antoni A, Antonio B (hypo, hyper cellular respectively)
- verocay body (looks kind of like a pacinian corpuscle)
