Pediatric tumors

Pediatric Neurosurgical Neuropathology● Brain tumors are second only to leukemias in... adult● Adults: 70% of tumors are supratentorial – meningioma – pituitary adenoma – High grade ast

Pediatric Neurosurgical Neuropathology

● Brain tumors are second only to leukemias in

CNS tumors: pediatric vs adult

● Adults: 70% of tumors are

supratentorial

– meningioma

– pituitary adenoma

– High grade astrocytoma

» Anaplastic astrocytoma (grade III)

» Glioblastoma multiforme (grade IV astrocytoma)

● Pediatric: 70% in posterior fossa

– pilocytic astrocytoma (cerebellar

astrocytoma)

– medulloblastoma

Brain tumors: intro

Primary brain tumors: intro

● Primary brain tumors are rare

– 2.5% of all cancer deaths

– Second most common type of tumor in children – There are over 100 different brain tumors

● Most common types

– Astrocytomas

» Grades I-IV– Medulloblastomas

» primitive neuroectodermal tumor-PNET– Meningiomas

– Pituitary adenomas

Clinical presentation

● Clinical symptoms depend upon:

– Age, location, and type of tumor and grade

● Symptoms may include:

– Increased intracranial pressure

» secondary to obstruction of CSF at aqueduct

» hydrocephalus (infants), headache, papilledema,

vomiting

– seizures

– focal neurological deficits

– hormonal changes (pituitary adenoma)

– visual changes (diplopia, field defects)

» Pituitary adenoma - pressure on optic chiasm

» typical of high grade

» also in some low grade, i.e., pilocytic

astrocytomas

CNS tumors: location

● Extra-axial

– meningiomas

● Cerebral hemispheres

– grade II-III astrocytomas, GBM

● Crossing corpus callosum - GBM

● optic nerve - pilocytic astrocytoma 1)

(NF-● Sella - Pituitary adenoma

● Peri-III ventricle - Pilocytic astrocytoma, GBM

Pilocytic astrocytomas

– Most common in children

– Grade I astrocytoma

– Cerebellum (posterior fossa), optic nerve

» Thalamic, spinal cord, cerebral

– Discrete, well circumscribed mass

– Often with associated cystic area

Pilocytic astrocytomas

Tumor of cerebellum, often with cyst, biphasic, Rosenthal fibers, piloid cells

Astrocytoma - high grade

● Astrocytoma grade II and III are very, very rare

in the pediatric population

● Grade IV - glioblastoma multiforme

● Diffusely infiltrating glial tumor of cerebral

Glioblastoma (grade IV)

● Less common in children than adults, typical pathology (necrosis with psuedopallisading)

Pontine glioma

Diffuse expansion of pons, usually high grade astrocytoma (III-IV)

– neuronal or glial differentiation

» Homer Wright rosettes

» GFAP positive cells

Meningiomas

Extra-axial tumor, meningothelial cells, whorls and psammoma bodies

Cerebrum, cervicomedullary, often with cystic component

Increased numbers of neurons (some binucleate) and increased glial cells (usually astrocytic)

● Heterogeneous, cystic mass in suprasellar region

● Basiloid layer, stellate reticulum, “wet” keratin, often calcified

Choroid plexus papilloma

● Lateral ventricle in children (fourth

ventricle in adults)

Germ cell tumors

● Pineal - 99% males, most are germinomas

● Suprasellar - often mixed germ cell tumor, 50% female

● Tertomas are rare

Germinoma Teratoma

Metastatic tumors

● The most common “brain” tumor in

adults is metastatic

● Metastatic tumors are rare in children

● The most common metastatic tumor in children

is osteosarcoma

● Local extension of malignant tumors of

vertebral bodies (Ewing’s sarcoma) or

paravertebral soft tissues (neuroblastoma) are not uncommon

Other tumors

● Subependymal giant cell astrocytoma (SEGA)

– Intraventricular tumor in Tuberous sclerosis

● Desmoplastic infantile ganglioglioma (DIG)

– Superficial cerebral tumor in infants

● Dysembryoplastic neuroepithelial tumor (DNET)

– Hamartomatous lesion associated with seizures

● Atypical teratoid rhabdoid tumor (ATR, AT/RT)

– Infants, posterior fossa, very malignant

● Eosinophilic granuloma

– A type of Langerhans cell histiocytosis

– Single discrete osteolytic lesion in skull

● Meningioangiomatosis

– Hamartomatous superficial cerebral lesion associated with seizures