Chordoid glioma : a case report of unusual location and neuroradiological characteristics

Abstract

Since the World Health Organization (WHO) classification for central nervous system neoplasms was declared in 2000, chordoid glioma of the third ventricle has been noted as a newly recognized tumor for central nervous system neoplasms. Although there is not enough universal experience to know the nature of this tumor due to its rarity, the origin of chordoid glioma was guardedly proposed to be the ependymal cells of the third ventricle. Such an idea has been primarily based on the specific location of the tumor, that is, third ventricle, suprasellae, and hypothalamus. However, we report a rare case of histologically confirmed chordoid glioma located in the left thalamus, not attached to any of the midline structures having unusual neuroradiological characteristics.

Keywords: Chordoid glioma; Radiological feature; Third ventricle.

Fig. 1

Magnetic resonance images of the tumor. A : T2-weighted image shows a well-defined high signal mass in the left thalamic pulvinar area without any involvement of the third ventricle. B : T1-weighted image shows low signal intensity of the mass. C : Gadolinium-enhanced T1-weighted image shows scattered dot-like subtle enhancement of the tumor, suggestive of the possibility of intermediate grade glioma.

Fig. 2

Magnetic resonance spectroscopy. Single-voxel MR spectroscopy performed in the central portion of the tumor shows high choline, low N-acetyl aspartate (NAA), and equivocal lactate. The box on the tumor indicates the voxel.

Fig. 3

Histological findings. A : Hematoxylin and eosin staining revealed clusters and cords of epithelioid cells, abundant myxoid and mucinous stroma, well developed capillary network, mild nuclear pleomorphism, no mitosis, no vascular endothelial hyperplasia, and no necrosis (H & E,×100). B and C : Photographs of immunohistochemical stainings demonstrating diffuse cytoplasmic expression for glial fibrillary acidic protien (B) and vimentin (C) (×200).