Central neurocytoma: clinical, pathological and neuroradiological findings

To evaluate the clinical, pathological and neuroradiological features of intraventricular central neurocytoma in six patients.

Six patients were imaged using non-enhanced and contrast-enhanced magnetic resonance imaging (MRI); three of them were also examined using non-enhanced computed tomography (CT). Two radiologists read the images retrospectively. The imaging data were studied with regard to location, size, margin, signal intensity, enhancement characteristics and presence of calcifications. Clinical data (i.e. presenting signs and symptoms, physical findings and medical histories) were collected and histopathological and immunohistochemical studies were performed by two pathologists.

All lesions were located in the lateral ventricles. Three tumors were confined to the left side, one to the right side and two cases involved both lateral ventricles. The growth of central neurocytoma was of close spatial relation to the septum pellucidum. On MRI, most of the cases showed a heterogeneous hypointensity on T1-weighted images and hyperintensity on T2-weighted images or FLAIR with a well-defined margin. The presence of cystic components, necroses and calcifications caused these internal heterogeneities. After intravenous administration of gadolinium (Gd-DTPA) all tumours showed a heterogeneous enhancement. CT provided additional information by distinguishing intratumoural calcifications in all three evaluated cases. Immunohistochemical analysis showed positive synaptophysin staining in all cases and positive neuron-specific enolase staining in four cases. In three cases a small proportion of the tumour cells could be labelled with antibodies to glial fibrillary acid protein (GFAP).

Central neurocytoma should be considered when the following conditions occur: young patients with lesions in the lateral ventricle, which contain calcifications and show some enhancement. This is especially applicable for tumours involving both lateral ventricles with symmetrical growth around the centre of septum pellucidum or for unilateral ventricular tumors with a wide base attachment to the septum pellucidum.