Pediatric Brain Tumors
Second most common malignancy in children, 20% of all tumors (leukemia is the first)
Most common solid tumor in children
In children < age 2 and in adolescents, about 1/2 of brain tumors are infratentorial
2/3 of brain tumors in children ages 2‑12 are infratentorial (posterior fossa)
think: if < 1 y/o supratentorial, if 1-10 yo mostly infratentorial, > 10yo, infra=supra
Cell of origin:
Glial cell: astrocytoma, ependymoma, glioblastoma multiforme
Meningioma, teratoma, neurocytoma
Neuroectodermal: arise from a primitive cell line
Causes
Hereditary: NF, tuberous sclerosis
NF I ‑ increased incidence of optic glioma and low‑grade astrocytoma
NF2 ‑ increased incidence of acoustic neuroma. and meningioma
Embryonic remnants: craniopharygnioma (Rathke's pouch), teratoma
Radiation: meningiomas, ALL
Immune deficiency: CNS lymphomas
Clinical manifestations:
Signs/symptoms of ICP due to CSF obstruction, hydrocephalus: headache, nausea/vomiting (80%), diplopia, papilledema, bulging fontanelle/macrocephaly
Headache typically occurs in the morning and improves with standing, vomiting
Headache worsens with coughing/sneezing/defecation
Headaches are recurrent, localized and unresponsive to meds
Seizures in 15%
Alterations of personality/behavior can be an early signs
Supratentorial tumors are more likely to present with focal deficits (ie hemiparesis) and seizures than infratentorial tumors
Midline tumors tend to present with: vision disturbance (diplopia, bitemporal hemianopsia), endocrinopathy, diencephalic syndrome, Parinaud syndrome
Infratentorial tumors present with: hydrocephalus, macrocephaly, ataxia, increased ICP, diplopia
Treatment, in general
treatment is surgery for all except brainstem gliomas
radiation is deferred in children because of cognitive impairment risk
chemotherapy, especially used in infants
where radiotherapy is too dangerous; see
Complications of
chemo: general
Questions:
what are the 5 most common brain tumors in children?
what is the most common posterior fossa tumor in children?
what is the second most common ... ?
what is the most common brain tumor in children under 7 y/o?
what is the third most common posterior fossa tumor in children?
what is the most common supratentorial tumor in children
which malignant tumor has the best px?
which primary brain tumor has the worst px?
5 most common brain tumors in children: ABCPE
Astrocytoma 40%
brainstem glioma 10%
craniopharyngioma 10%
PNET (medulloblastoma) 20%
Ependymoma 10%
Infratentorial/posterior fossa tumors:
Cerebellar astrocytoma has the best prognosis and is the most common posterior fossa tumor in children (>90% 5 year survival after resection), usually treat with resection alone; as opposed to cerebral astrocytoma (poor px)
Medulloblastoma (PNET is the official name)
the second most common posterior fossa. tumor
"small blue cells"
age 3-6 y/o (younger); is the most common brain tumor in children < age 7
It often originates in the roof of the fourth ventricle and may rapidly fill the ventricle and invade the cerebellum. 2/3 arise in cerebellar vermis.
may have spinal sx i.e. bowel/bladder incontinence, back pain.
most common X-ray finding is sutural diastasis
It also has a propensity to metastasize to distant sites, incl spinal cord, brain
80‑90% 5 year survival with resection/chemo/radiation
Brain stem glioma is the third most common posterior fossa tumor and can be divided into two types: tumor that infiltrates diffusely in the pons and brainstem (anaplastic astrocytoma), and low‑grade focal tumors of the midbrain or medulla. The first type has a very poor prognosis (10% 2 year survival) and treatment is radiation, no surgery. The second type has excellent survival rates after resection alone. These usually present first with cranial nerve deficits and later with ICP (once the tumor is large enough to obstruct CSF).
Ependymoma
accounts for 10% of posterior fossa tumors
70% infratentorial
arises from the fourth ventricle; cells line ventricle/spinal canal
present with signs of ICP as well as possible nuchal rigidity and torticollis secondary to herniation of the cerebellar tonsils.
treatment: surgical resection
rare mets within CNS
(50% 5 year survival except for anaplastic ependymoma which has poor prognosis)
Supratentorial tumors:
Cranio‑pharyngioma is one of the most common supratentorial tumors in children. These tend to start in the sella turcica and may expand; patients present with signs of pituitary involvement, ICP. Endocrine disorders may develop post‑op.
age 7-12 (older)
Calcifications seen with 90%
visual field deficits: bitemporal hemianopsia
treatment - surgery
Optic nerve glioma presents with visual changes and disc pallor. Most are low-grade astrocytornas
Cerebral astrocytoma has a worse prognosis than cerebellar astrocytoma and survival depends on the grade of the tumor.
Pineal gland tumor is a category which includes various germ cell tumors, pinealomas, pineoblastomas, and teratomas which vary greatly in their degree of malignancy and local invasion.
Choroid plexus papilloma presents as slowly progressive hydrocephalus due to excess CSF production. This tumor has an excellent prognosis after resection.
Leukemic infiltrates
Meningiomas: arise from meninges; rare (<2% of brain tumors); headache, seizure, weakness
Both Supra and Infratentorial: astrocytoma, ependymoma, meningioma
Pseudotumor cerebri
Pseudotumor cerebri is a syndrome which may present similarly to a brain tumor
ICP may be secondary to alterations in CSF absorption/production, cerebral edema, abnormalities in cerebral blood flow, and/or venous obstruction.
Causes include metabolic disorders, infections, drugs, hematologic disorders, venous thrombosis, Guillain‑Barre, obesity, pregnancy, etc.
These patients have signs of ICP but do not have focal neurological deficits (the latter of which may be more suggestive of tumor or other disease)
Self‑limited disease but complications include optic atrophy and blindness
Adapted from Nelson Textbook of Pediatrics
CHLA Board Review 2005