Central Neurocytoma

KEY FACTS

TERMINOLOGY

• Central neurocytoma (CN) = intraventricular neuroepithelial

tumor with neuronal differentiation

IMAGING

• Best diagnostic clue: "Bubbly" mass in frontal horn or body

of lateral ventricle

○ May involve 3rd ventricle

• CT: Usually mixed solid and cystic mass with calcification

○ Hydrocephalus common

○ Rarely complicated by hemorrhage

• MR: Heterogeneous, T2 hyperintense, "bubbly" appearance

○ May be predominantly solid mass

○ Moderate to strong heterogeneous enhancement

• MRS: ↑ Cho, ↓ N-acetylaspartate; glycine peak at 3.55 ppm

• If "bubbly," "feathery," or solid intraventricular mass near

foramen of Monro in young adult, consider CN

TOP DIFFERENTIAL DIAGNOSES

• Subependymoma

• Subependymal giant cell astrocytoma

• Intraventricular metastasis

• Ependymoma

• Choroid plexus papilloma

CLINICAL ISSUES

• Young adults, commonly 20-40 years of age

• Usually benign, local recurrence is uncommon

○ Surgical resection is typically curative

○ If incomplete resection, radiation therapy,

chemotherapy, &/or radiosurgery may be helpful

• 5-year survival rate: 90%

• MIB-1 (Ki-67 labeling) index > 2-3% = poorer prognosis

• Headache, increased intracranial pressure, mental status

changes, seizure are most common presenting features

○ Hydrocephalus secondary to foramen of Monro

obstruction

(Left) Axial graphic shows a

circumscribed, lobular,

"bubbly" mass ﬇ attached to

the septum pellucidum ﬈.

Ventricular dilatation is

related to foramen of Monro

obstruction. This is the classic

appearance of a central

neurocytoma. Complete

surgical resection is often

curative for these WHO grade

II tumors. (Right) Axial NECT

shows a heterogeneous mixed

cystic/solid mass ﬈ in the

lateral ventricles attached to

the septum pellucidum. There

is associated obstructive

hydrocephalus ﬇, typical for

central neurocytoma.

(Left) Axial T2WI MR in a 20

year old with headaches

shows a predominantly solid

ventricular mass in the body of

the lateral ventricle ﬈

attached to the septum

pellucidum with prominent

flow voids ﬊. (Right) Axial

T1WI C+ MR in the same

patient shows diffuse

enhancement ﬈. Central

neurocytoma was diagnosed

at resection. Imaging

differential considerations

include subependymal giant

cell astrocytoma,

subependymoma, and

meningioma. (Courtesy S. van

der Westhuizen, MD.)

Cysts, and Disorders

Brain: Pathology-Based Diagnoses: Neoplasms,

141