Lec 63 CNS Tumors Flashcards
What causes localizing symptoms of brain tumors?
those caused by tumor invasion or compression of particular structures
ex: aphasia, weakness, visual field cut, seizure, etc
What causes non-localizing symptoms of brian tumors?
elevation in ICP due to mass itself, cerebral edema, or hydrocephalus secondary to obstruction
ex: N/V, headache, mental status change
What is most common location of tumors in adults vs children?
adults = supratentorial kids = infratentorial
What is mainstay of tumor therapy?
surgical resection
What are glial tumors [gliomas]? 3 types?
tumor of glial cells
- astrocytomas [malignant or not]
- ependymoma
- oligodendroglioma
What is most common type of primary brain tumor [glial or non-glial]?
glial = 80%
Where are gliomas usually located?
- frontal lobe
- insula
- parieto-occipital region
- splenium of corpus callosum
- thalamus
What is glioblastoma multiforme [GBM]?
- grade 4 astrocutyoma
- common, highly malignant primary brain tumor
- 1 year median survival
- found in cerebral hemisphere; can cross corpus callosum = butterfly glioma
What are the 4 grades of glioma called?
grade 1/2 = low grade 1 = fibrillary astrocytoma 2 = astrocytoma or oligodendroglioma 3 = anaplastic astrocytoma / oligodendroglioma 4 = GBM
What is treatment for glioma?
supportive care, surgery, try chemo/radiation
prognosis = < 1 year
What are risks for glioma?
age, male, ionizing radiation
3 pks of incidence: children, 30-40 yrs, > 65 yrs
What are symptoms of glioma?
increased ICP, seizures
What is life expectancy for low grade astrocytoma?
5 yrs
What is hemangioblastoma? where is it usually?
usually cerebellar
fried egg appearance
What is ependymoma? where is it usually?
usually in spaces of posterior fossa but also can be in spinal cord or region of cauda equina
most frequentyl in children/young adults
What are signs of infratentorial ependymoma?
N/V, headahce, other signs related to hydrocephalus, CN signs and symptoms
What is pathology of oligodendroglioma?
fired egg; chicken wire capillary pattern
often calcified
Where are ependymomas commonly found?
in 4th ventricle
What is prognosis of ependymoma?
poor prognosis, associated wtih hydrocephalus
What are characteristic pathologies of ependymoma?
characteristic perivascular rosettes, rod shaped blepharoplasts [basal ciliary bodies] near nucleus
Are ependymomas more frequently seen in children or adults?
children
What are characteristics of glial choroid plexus tumors?
- only tumors causing hydrocephalus by over-secretion of CSF rather than blockage
- classified as papillomas [benign] or carcinomas [malignant]
more common in childhood
most foten occur in 4th ventricle
What are signs of choroid plexus glial tumors?
high ICP [N/V, headache, lethargy], hydrocephalus [excess CSF], deficit eye movement due to pressure on roots of 3, 4, or 6
What are characteristics of meningiomas?
- second most common brain tumor
- arise from meninges
- typically benign primary tumor
- often asymptomatic
- may present with seizure or focal neurological signs, loss of small [if in olfactory groove]
What are risk factors for meningioma?
female, radiation, neurofibromatosis
What is pathology of meningioma?
dural tail = attachment to dura
extra axial = external to brain parenchyma
psammoma bodies and whorls of cells
What is treatment for meningioma??
resect if symptoms present, may need radiosurgery
What type of tumor should you think: pseudopalisading
glioblastoma
Where do meningiomas most often occur?
convexities of hemispheres near surface of brain and parasagittal region
What age group gets meningioma?
age 50-70 but grows slowly
What are characteristics of pituitary adenoma? what is most common type?
most common = prolactinoma
present with: bitemporal heminaopia due to pressure on optic chiasm, hyper or hypo pituitarism
Who commonly gets craniopharyngioma?
young children
What is a cranipharyngioma?
benign childhood tumor
may be confused with pituitary adenoma b/c both can cause bitemporal hemianopia
derived from remnants of rathke pouch, calcification common
What are characteristics of medulloblastoma?
highly malignant common childhood tumor
usually cerebellar tumor = get vermal symptoms and obstructive hydrocephalus
form of primitive neuroectodoermal tumor
can compress 4th ventricle
what are symptoms of pituitary tumors?
hyperprolactinemia [lactating, gynecomastia] or acromegaly [gigantism in children]
What is pathology of medulloblastoma?
homer-wright rosettes
sold [gross]
small blue cells
What is non-glial hemangioblastoma?
syndromic and hereditary = von hippel lindau [mut in tumor suppressor gene VHL]
can secrete erythropoietin
usually originates cerebellum
treated with embolization then surgery
what are characteristics of primary cerebral lymphoma?
associated with HIV, immunosuppression, EBV
primary B cell lymphoma
steroid sensitive + treated with chemo/radiation
often have cognitive impairment and poor outcome
Where do brain metastases usually come from?
lung > breast > melanoma, GI, renal
spread via blood
Are metastases infra or supratentorial?
supratentorial
How does subfalcine herniation present?
headache and as progresses –> contralateral leg weakness
How does transtentorial [central] herniation present?
pupils and respirations change depending on how far down brain it herniates
can lead to stupor, coma
- pupil irregular then fixed at midposition
- oculocephalic movements difficult
- extensor posturing spontaneously
- motor tone increased
What are signs of uncal herniation?
contralateral hemiparesis
CN III palsy [dilated pupil]
duret hemorrhages
can lead do decrease level of consciousness
What should you think if you have dilated pupil in absence of decreased consciousness?
NOT uncal herniation
What is kernohan’s notch?
sign of severe uncal herniation
causes false localizing sign = large mass effect pushes midbrain against opposite side of tentorium –> paradoxical hemiparesis ipsilateral to lesion instead of contralateral
CN3 still on ipsilateral leg: use pupil dilation > hemiparesis to localize the lesion
What are signs of tonsillar herniation?
cerebellar tonsils move down through foramen magnum –> compression of medulla oblongata and upper cervical spinal cord
may cause cardiac and respiratory dysfunction
What is vasogenic edema? cause?
breakdown of tight endothelial junctions [BBB]
due to: trauma, tumors, focal inflammation
What is cytotoxic edema? cause?
BBB intact –> problem in cellular function [NA/K pump]
seen in reyes syndrome, hypothermia, altitude, psuedomotor
What is interstitial edema?
seen in obstructive hydrocephalus
due to impairement in BB with transependymal flow of CSF
What is osmotic edema?
impaired osmolality of blood
