Tumor Type |
Incidence |
Location |
Diagnostic Features |
Treatment |
Prognosis |
Astrocytic |
Grade I/Pilocytic astrocytoma |
20% of astrocytomas
Male = Female Peak, 5-14 yo Increased in NF1 |
Cerebellum (most) Brainstem
Optic pathway
Hypothalamus |
CT/MRI: 50% well circumscribed
Cyst with mural nodule Contrast enhancing
Solid parts with low attenuation relative to cerebellar parenchyma
Path: Rosenthal fibers |
Maximal surgical resection
± Chemotherapy
± RT |
Total surgical resection is curative in 95%-100%
May stabilize for long periods |
Grade II/ Diffuse astrocytoma |
15% of astrocytomas
Peak, 2-4 yo and early adolescence |
Frontal and temporal lobes > brainstem and spinal cord |
MRI: heterogeneous
CT: solid parts are low density
Path: ft cellularity, diffuse infiltration of neighboring brain structures |
Maximal surgical resection
± Chemotherapy
± RT |
With gross total resection, 80%-100% survival
With partial resection, 50%-95% survival
Worse prognosis if tumor is midline |
High-grade astrocytoma
Anaplastic astrocytoma/
Grade III Glioblastoma/Grade IV |
10% of pediatric tumors
Peak, 9-10 yo |
Most are supratentorial |
CT/MRI: often with mass effect, variable contrast enhancement, areas of necrosis (if grade IV), restricted diffusion
MRS: low choline, high citrate
Path: increased cellularity, atypia; grade IV with vascular proliferation and necrosis |
Maximal surgical resection
± Chemotherapy and RT |
5-y survival rate is 15%-30% for supratentorial lesions, <10% for pontine |
Pleomorphic xanthoastrocytoma |
<1% of all astrocytomas; typically develops in children and adolescents |
Cortical/hemispheric predominance
Most common origin = temporal lobe |
MRI: peripheral hemispheric mass w/heterogeneous enhancement post contrast
Solid parts show signal intensity similar to gray matter |
Maximal surgical resection
Seizure management |
Recurrence-free survival rates of 72% at 5 y and 61% at 10 y |
Subependymal giant cell astrocytoma |
Almost exclusive to TSC patients
Peak, 1st decade |
Most in lateral ventricle, near foramen of Monro |
MRI: circumscribed, homogenously enhancing mass characteristically located within the lateral ventricle |
Maximal surgical resection
Seizure management CSF diversion mTOR inhibitors |
Survival ˜95% at 5 y |
Oligodendroglioma
Well-differentiated/WHO grade II)
Anaplastic/WHO grade III) |
1% of childhood brain tumors |
Supratentorial |
CT: presence of dense nodular calcification suggests diagnosis; osseous remodeling of skull inner table to the skull is common, mineralization frequent
MRI: predominantly solid mass centered peripherally in the cerebral hemispheres
Histology: honeycomb/ground glass appearance |
Maximal surgical resection
± Chemotherapy and RT if recurrence |
10-y survival rate up to 80% |
Ependymoma |
8%-10% of childhood brain tumors
Peak, 0-5 yo; 30% < 3 yo |
Posterior fossa (60%)
Supratentorial tend to occur in a periventricular location
May have drop metastases at presentation (10%) or at recurrence |
MRI: usually heterogeneously enhancing, along the ventricular lining; cerebellopontine predilection; tend to extend through the outlet foramina of the 4th ventricle; mineralization, necrosis, and hemorrhage common, isointense to gray matter
LP: check for leptomeningeal spread |
Maximal surgical resection ± RT
Chemotherapy may delay RT |
Prognosis depends on extent of resection, age, and tumor location |
Choroid plexus
Choroid plexus papilloma (CPP)
Choroid plexus carcinoma (CPC) |
2%-4%
If <1 yo, 10%-20% (80% CPP, 20% CPC)
Peak, 0-5 yo |
Lateral ventricle (50%); 4th ventricle (40%)
Associated with Li-Fraumeni |
MRI: markedly lobulated, often frondlike, solid mass within ventricle
CPC is more heterogeneous ± necrosis and parenchymal invasion ± CSF dissemination
Both will enhance post administration of IV contrast
MRS: CPP marked inc of myoinositol; CPC marked inc choline |
Maximal surgical resection
Multiagent chemotherapy for CPC |
CPP: 10-y survival, 85% if gross total resection
CPC: 5-y survival, 26% (most deaths occurring within 7 mo of surgery)
May metastasize if associated with Li-Fraumeni |
Neuronal and mixed neuronal-glial |
Dysembryoplastic neuroepithelial tumor (DNET) |
Overall incidence of ˜1%. In one study, 18%-19% of patients undergoing temporal lobe resection for refractory epilepsy had a DNET
Often presents with seizures |
Always centered in cerebral cortex (temporal > frontal lobes) |
CT: peripherally located, low density mass
MRI: circumscribed mass centered within the cerebral cortex; involvement of subcortical WM is not uncommon and tends to show a centripetal tapering
Cystic components are common (soap bubble appearance)
MRS: normal
Pathology: may have surrounding areas of dysplasia |
Maximal surgical resection |
Have potential for recurrence following complete surgical resection
Seizure control may be challenging |
Ganglioglioma |
3% of brain tumors; 6% of all supratentorial tumors in children
Peak, adolescence
Often presents with seizures |
Cerebral cortex, most commonly the temporal lobe |
CT: mineralization common
MRI: peripherally located, intra-axial, wholly solid or partly cystic |
Maximal surgical resection |
Potential for recurrence following complete surgical resection
Seizure control may be challenging |
Germ cell tumors |
Germinoma nongerminomatous germ cell tumor (NGGCT) |
1%-2% of childhood brain tumors
Mean age at diagnosis, 10-12 y
M:F = 2-3:1 |
Suprasellar more common in females; pineal more common in males
Can have synchronous or consecutive tumors |
MRI: predominantly solid, suprasellar mass with signal characteristics approximating that of gray matter
If suprasellar, often pituitary bright spot is absent
Labs: for germinoma, markers negative; for NGGCT, elevated α-fetoprotein and βHCG |
Diagnostic biopsy if markers negative
RT for germinoma
RT+ chemotherapy for NGGCT
May require CSF diversion |
Germinoma: most localized germinomas can be cured with RT therapy alone, survival is 65%-95% @ 5 y
NGGCT survival, 40%-70% @ 5 y. High-dose chemotherapy and stem cell rescue at relapse |
Teratoma |
2nd most common germ cell tumor of the pineal region
Most common neonatal tumor |
Usually pineal |
MRI:
Benign form—marked heterogeneity; coexistence of cystic, solid enhancing, fatty, and mineralized components
Malignant form—a predominantly solid, enhancing mass without associated fat or mineralization |
Diagnostic biopsy if markers negative
May require surgical resection
May require CSF diversion |
Survival is dependent upon location and the patient’s ability to tolerate gross total resections |
Parenchymal tumors of pineal gland |
Pineoblastoma
Pineocytoma |
Each account for up to 45% of all tumors in the pineal region
Peak, 1st decade (pineocytoma are most common in 25-35 yo) |
Pineal |
MRI:
Pineoblastoma—heterogeneous enhancement post contrast administration; leptomeningeal dissemination may occur, and/or necrosis and hemorrhage
Pineocytoma—partially cystic mass, commonly associated with mineralization
Pathology: pineoblastoma; (small round cell tumor; histology similar to PNET) |
Diagnostic biopsy with resection if possible
May require CSF diversion
May consider markers to exclude NGGCT
Pineoblastomarelated RT + chemotherapy |
Operative morbidity high
Pineocytoma often has metastases at diagnosis, prognosis is poor, survival is 86% @ 5 y
Pineoblastoma survival is 58% @ 5 y after treatment with various modalities |
Primitive neuroectodermal tumors (PNET) |
Supratentorial PNET |
5% of all supratentorial tumors in children
Peak, 0-5 yo |
Hemispheric |
CT: calcification and osseous erosion
MRI: large, heterogeneous, often with necrosis, cystic degeneration, and hemorrhage; heterogeneous enhancement; isodense to gray matter
MRS: markedly elevated choline peak |
Maximal surgical resection
Chemotherapy + RT |
Prognosis is dependent upon risk category
Local relapse is a more significant failure pattern in supratentorial PNET than in medulloblastoma |
Primitive neuroectodermal tumors (PNET) |
Medulloblastoma |
15%-20%
Peak, 5-9 yo
M:F = 2.4:1 |
Posterior fossa |
MRI heterogeneous; enhancing mass; 30%—40% disseminated at diagnosis
MRS: elevated choline peak
LP: check for leptomeningeal spread |
Maximal surgical resection
Multiagent chemotherapy
If >3 yo, craniospinal RT with focal boost |
Standard risk, 85% survival High risk, 65% survival Poorer prognosis in infants, large cell/anaplastic variant
Molecular stratification will guide future therapies |
Atypical teratoid rhabdoid |
1.5-2.1% of childhood CNS tumors
Peak, <2 yo |
Posterior fossa Can be supratentorial |
MRI: signal intensity similar to gray matter; heterogeneous secondary to frequent necrosis and sometimes hemorrhage
Path: loss of INI1 staining on immunohistochemistry |
Maximal surgical resection
Multiagent (+ intrathecal) hemotherapy
If >3 yo, craniospinal RT with focal boost |
5-y survival 35% |
Meningeal |
Meningioma (wide range of histopathologic appearances that classify them as WHO grade I/II/III) |
Rare in children and adolescence
May be associated with NF2 or prior history of RT |
Most commonly vertex or orbital in children |
CT/MRI: homogeneous enhancement is the rule with dural tail
Hyperostosis of adjacent osseous structures is suggestive |
Maximal surgical resection if symptomatic
Seizure control |
After surgical resection, WHO grade I recur in 7%-20%; grade II in 29%-40%; grade III in 50%-78%
Malignant histologic features correlate with shorter survival times |
Sellar/Suprasellar |
Pituitary adenoma |
Increased incidence with improved detection
17% of all pituitary neoplasms (and only a minority are symptomatic)
Prolactinoma type is the most common |
Hormonally active > inactive
macroadenoma >1 cm; microadenoma >1 cm |
MRI: relative hypoenhancement compared with normal surrounding pituitary glandular tissue
A significant fraction of macroadenomas are hemorrhagic |
Hormonal therapy
If surgical intervention required, trans-sphenoidal surgery is treatment of choice |
Initial remission rate of 83% |
Craniopharyngioma (WHO grade I) |
7%-10% of all childhood brain tumors
Peak, 2nd decade and 4th-5th decades |
Originate within the sellar or suprasellar region |
MRI: large multilobulated heterogeneous masses with cystic and solid component; may be T1 hyperintense secondary to high cholesterol or protein content
CT: may show calcification
Path: most with adamantinomatous histology |
Maximal surgical resection
RT if incomplete resection or recurrence
Chemotherapy not helpful |
Postoperatively often with panhypopituitarism
May need stress-dose steroids
10-y progression-free survival rate 60%-93% in a large series, the most significant prognostic factor associated with tumor recurrence is the extent of surgical resection |
Hypothalamic hamartoma |
Rare and most occur sporadically; may be associated with TSC or Pallister—Hall syndrome (10%) |
Hypothalamus |
CT: appears as a gray matter density, suprasellar mass
MRI: round or ovoid mass centered at, or pedunculated from, the tuber cinereum. Does not enhance with contrast |
Endoscopic disconnection if possible
Seizure control |
Dependent upon ability to treat seizures (manifesting as several types, including gelastic) in addition to endocrinological and behavioral side effects |
Spinal cord |
2%-4% of all primary CNS tumors, 1/3 in the intramedullary compartment |
Extradural
Metastases (neuroblastoma, sarcoma, medulloblastoma, ependymoma)
Intradural—extramedullar
Meningiomas, nerve sheath tumors (schwannoma, neurofibroma)
Intradural—Intramedullary
Astrocytoma, ependymoma, myxopapillary ependymoma |
MRI: mass; appearance depends on tumor type |
Surgical resection is the mainstay of treatment
Observation for low-grade tumors postresection
Systemic therapy for relapse after maximal surgery and/or radiation
Consideration for radiation therapy depending on histology
Metastases have added increased risk for spinal cord compression |
Depends on tumor histology |
AA, anaplastic astrocytoma; ADC, apparent diffusion coefficient; AT ataxia; CPC, choroid plexus carcinoma; CPP, choroid plexus papilloma; CSF, cerebrospinal fluid; CT, computed tomography; DFA, diffuse fibrillary astrocytoma; DIPG, diffuse intrinsic pontine glioma; DNET, dysembryoplastic neuroepithelial tumor; FLAIR, fluid-attenuated inversion recovery; GBM, glioblastoma multiforme; JPA, juvenile pilocytic astrocytoma; LCH, Langerhans cell histiocytosis; MRI/S, magnetic resonance imaging/spectroscopy; NF-1, neurofibromatosis type 1; NGGCT, nongerminomatous germ cell tumor; OAC, oligoastrocytoma; ODG, oligodendroglioma; PBL, pineoblastoma; PCY, pineocytoma; PNET, primitive neuroectodermal tumor; PXA, pleomorphic xanthoastrocytoma; RT, radiation therapy; TSC, tuberous sclerosis complex; VHL, von Hippel—Lindau; WM, white matter.
From Louis DN, Ohgaki H, Wiestler OD, et al. WHO Classification of Tumors of the Nervous System. Lyon, France: IARC; 2007 and Paldino, Faerber EN, Poussaint TY. Imaging tumors of the pediatric central nervous system. Radiol Clin North Am. 2011:49:589-616, with permission. |