CNS neoplasms Flashcards
(41 cards)
How common are primary malignant brain tumors?
- 2% of all cancers in US adults
- over 120 types of brain tumors
- incidence higher in men than women
- peaks b/t 65-79 years
- more in children and older adults
- 2nd leading cause of death in children behind leukemia
RFs of primary malignant brain tumors?
- genetic mutation
- neurofibromatosis (assoc of tumors all over body)
- exposure to high dose ionizing radiation:
radiation therapy
atomic bomb survivors
CT scans, dental xrays
-studies show slight increase in these groups:
lab researchers, healthcare professionals
electric workers
prior head trauma
Classification of CNS neoplasms?
- based on cellular origin and histologic appearance:
grade 1-IV:
I: benign (still dangerous)
II: malignant
III: malignant tissue that has cells that are actively growing
IV: malignant tisue has cells that look most abnormal and tend to grow quickly
Tumor classification?
- neuroglial (glioma): astrocytoma oligodendroglioma ependymoma -meningioma -schwannoma: acoustic neuroma
What is glial tissue? How common are gliomas?
- is supportive tissue of the brain
- derived from astrocytes, oligodendrocytes, or ependymal cells
- encompasses 30% of all primary brain tumors and 80% of malignant brain tumors
Astrocytic tumors?
- glioblastomas
- astrocytomas
- together these make up 76% of gliomas
Grading of astrocytic tumors?
- grade I: benign (excision is curative) almost always dx in childhood
- grade II: slow growing and invade surrounding tissue
- grade III: rare and require aggressive tx due to tentacle like growth are hard to resect
- grade IV: called glioblastoma, aggressive fast growing cancer
Glioblastoma -location, tx, and survival?
- generally located within cerebral hemispheres of brain
- usually HIGHLY malignant
- most common malignant brain tumor
- 60-75% of all astrocytomas
- very difficult to remove due to finger like tentacles
- survival is about 2 years
- tx: surgery, radiation and chemo (debulk tumor - cause less sxs, if inoperable - chemo/rad)
What are oligodenrogliomas?
Grade? Growth?
- 2% of primary brain tumors
- can be grade II-III (malignant)
- most common in frontal or temporal lobes
- can have areas of hemorrhage
- generally slow growing and present for years before dx
Most common presenting sxs of oligodendrogliomas?
Tx?
- most common: seizure
- if frontal lobe tumors - may cause:
weakness on one side of body, personality changes, behavior changes, difficulty with short term memory
(TBI sxs)
Tx:
surgery
radiation
chemo
Prognosis of oligodendrogliomas?
- better prognosis compared to astrocytic tumors
- from time of dx to median time of surviva; 4-10 years
Ependymoma occurrence?
- ependymal cells line ventricles and center of spinal cord
- relatively rare in adults (2-3% of brain tumors)
- more common in children
- bimodal distribution peaks at age 5-6 and 20-30 years
Most common in kids? spinal cord or intracranial? sxs assoc with this?
- intracranial more common
- poor prognosis
- sxs are from IICP:
hydrocephalus
HA
N/V
ataxia
strabismus
irritability
altered mental status
Most common ependymoma tumor in adults? sxs?
- spinal cord
- better prognosis
- may cause cord compression sxs: paralysis, weakness, herniated disc sxs, won’t present with seizures or other UMNL sxs,
What is a meningioma? How common is this?
- derived from meningothelial cells that arise from coverings of brain and spinal cord
- 20-30% of primary brain tumors
- most common primary brain tumor
Meningioma characteristics?
Tx?
- more common in women
- often benign
- usually grow inward putting pressure on brain and spinal cord
- can grow outward and cause thickening of skull
- tx: surgery and radiation
Meningioma prognosis?
- est 5 year survival rate is 73-94%
diff to estimate due to many people found to have meningiomas die from other causes - tx: surgery and radiation
Sites where meningiomas can develop? Sxs?
suprasellar, optic sheath, paranasal/olfactory, foramen magnum, clivus
sxs:
- irritation: seizures
- compression: HA, focal weakness, dysphagia, apathy, somnolence
- stereotypic: CN deficits, change in mentation, visual changes, anosmia, exopthalmos, tongue atrophy
- vascular: compression of cerebral arteries
- misc: hydrocephalus, panhypopituitarism
Tumors of the cranial and paraspinal nerves?
- schwannoma
- neurofibroma
- perineurioma
- malignant peripheral nerve sheath tumor
What are schwannomas?
- nerve sheath tumor composed of schwann cells
- relatively slow growing
- mostly benign and less than 1% become malignant
- tumor cells always stay on outside of nerve (tumor itself may either push the nerve aside and/or up against a bony structure thereby possibly causing damage
Most common schwannoma?
- acoustic neuromas
Characteristics of acoustic neuromas?
- arises from 8th CN
- benign
- usually slow growing
- can cause serious complications and even death if they grow and exert pressure on nerves and eventually on brain
- other locations include spine and more rarely along nerves that go to the limbs
Sxs of acoustic neuromas?
- unilateral hearing loss
- tinnitus
- occasional dizziness
- difficulty swallowing
- impaired eye movement
- taste disturbance
- unsteadiness
- HA
Tx of acoustic neuromas?
- surgical excision
- stereotactic radiation surgery to arrest growth
- in some cases tehy are followed by observation for growth:
small tumor size, not sig sx, elderly, poor surgical candidates or pt declines other tx