2. Epidemiology
Half of all brain and spinal cord tumors are
metastatic
The most frequent primary CNS tumors are
glioblastoma multiforme and meningiomas
Primary malignant CNS tumors account for 2-
3% of all cancer deaths in the U.S.
3. Clinical manifestations
Headache – often worse at night or early
morning
Seizures – tumors involving cerebral cortex
Mental changes – deficits in memory,
concentration, reasoning
Focal neurological symptoms are related to
involvement of specific brain regions
Symptoms related to increased ICP are due to
the presence of a space-occupying mass w/in
the cranial cavity, blockage of CSF flow, and
peritumoral edema
4. Primary Versus Metastatic Tumors
Primary
Poorly circumscribed
Usually single
Location varies according to
specific type
Metastatic
Well circumscribed
Often multiple
Usually located at the junction
between gray and white matter
6. Glioblastoma multiforme (Grade IV
astrocytoma
The most common CNS primary
malignancy in adults
Most common location is white
matter in the centrum semiovale
Characteristic histopath. feature is an
area of necrosis surrounded by rows
of neoplastic cells (pseudopalisading
necrosis)
Aggressive tumors – poor prognosis, 1 yr.
median survival
Originate from astrocytes and immunoreact
w/ GFAP
Has a tendency to cross the midline by
involving the corpus callosum – “butterfly
glioma”
8. Meningioma
Common, typically benign
Originates from meningothelial cells
of the arachnoid
Women more than men
Attach to dura and push underlying
brain w/o invasion
Composed of spindle shaped cells w/
indistinct borders; arranged in whorls or
fascicles
Psammoma bodies are frequent
Rx: resection and/or radiosurgery
12. Schwannoma
Originates from schwann cells of
cranial or spinal nerves
Most frequent location is on the 8th
CN at the cerebellopontine angle
Classical presentation of tinnitus and
loss of hearing
Good prognosis after surgical resection or
treated w/ stereotactic radiosurgery
Bilateral acoustic schwannomas are
pathognomonic of NF Type 2
The neoplastic cells are immunoreactive with
S-100 protein
14. Oligodendroglioma
Most often in frontal lobes white
matter
30-50 year old patients
Often manifests w/ seizures
Relatively rare, slow growing, 5-10
year survival
Tend to recur after surgery and eventually
degenerate into high-grade gliomas over
time
Neoplastic cells similar to oligodendroglia
w/ pronounced perinuclear halo
16. Pituitary Adenoma
Most commonly prolactinoma
Manifests w/ bitemporal hemianopia
due to pressure on optic chiasm
Hyper or hypo-pituitarism are
sequelae
Monomorphic neoplastic cells
18. References
Le, T., Bhushan, V., & Sochat, M. (2014). First Aid for the USMLE Step 1: Adult primary
brain tumors. McGraw-Hill Education New York, NY.
Sanchez, H. and Barone, J. (2011). Kaplan Medical USMLE Step 1 Pathology: CNS
Pathology. Kaplan Publishing. New York, NY.
Fischer, C. (June 2015). Master the Boards USMLE Step 2 CK: Oncology. Kaplan
Publishing. New York, NY.
