CNS TUMORS
DEFINITION:
A solid tumor of the CNS characterized usually by increased
intracranial pressure and/or focal neurologic signs.
EPIDEMIOLOGY:
- incidence: 3.3/100,000
- most common solid tumor of childhood
- 2nd most common form of childhood CA (20%)
- 2nd most common cause of childhood CA-related deaths (< 15
yrs)
- age of onset:
- medium age at time of diagnosis: 5 yrs
- only 15% occur in infants < 2 yrs.
- risk factors:
- neurocutaneous syndromes
- immune dysfunction
- AIDS
- ataxia telangiectasia
- Non-Hodgkin's Lymphoma
- environmental factors
- parental exposure to organic carcinogens
- radiation exposure in utero
- therapeutic radiation for tinea capitis or primary CA
- familial
- chromosomal abnormalities
PATHOGENESIS:
- represent primitive undifferentiated cells
- involve the cerebrum, pineal gland (pineoblastoma),
cerebellum (medulloblastoma), spinal cord
2. Glial Tissue
- most CNS tumors arise from glial tissue
- this supporting tissue is ectodermal in origin
- 3 types:
- star-like cells arising from astroblasts
- give rise to astrocytomas
- cerebrum, corpus callosum, optic chiasm & nerve,
cerebellum, brain stem, around 3rd ventricle
2. Ependymal Cells
- give rise to ependymomas
- cerebrum, ventricles, cerebellopontine angle
3. Oligodendrocytes
- tree-like cells arising from oligodendroblasts
- give rise to oligodendroglioma
- cerebrum, corpus callosum, around 3rd ventricle
CLINICAL FEATURES:
- two distinct patterns of presentation:
- diplopia, headache, papilledema, vomiting
2. Cerebellar Signs
- vermis - truncal ataxia enhanced with sit/standing
- lateral - ipsilateral extremity ataxia,
dysdiadocho-kinesia
- anterior - broad-based gait
- visual - nystagmus, obscuration of vision, head
tilting & nuchal rigidity
3. Coning
- hydrocephalus, Cushing's Reflex, coma
2. Supratentorial
- hemiparesis, complex partial seizures
2. Personality Changes
2. Metastases
INVESTIGATIONS:
3. Biologic
MANAGEMENT:
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