Primary intraventricular gliosarcoma on MRI: A challenging diagnosis

Abstract

Gliosarcoma (GS) is an uncommon central nervous system tumor with several characteristics of a malignant neoplasm and poor prognosis. The majority of GS reports describe a predilection for the cerebral hemispheres, and cases of intraventricular GS are extremely rare, with only a few reported. In addition, intraventricular GS has not been associated with any unique radiographic or clinical features, which can result in misdiagnosis as other intraventricular tumor types. In this report, we present the case of a 32-year-old woman with GS in the trigone of the lateral ventricle and provide a retrospective review of similar, previously reported cases.

Keywords: Gliosarcoma; Intraventricular; Magnetic resonance imaging.

Fig. 1

(A–F) A mixed-signal mass (star) was observed in the trigone of the right lateral ventricle, surrounded by moderate vasogenic edema (black arrow in A and B). Post-contrast heterogeneous enhancement and the thickening of the ependymal membrane with uniform enhancement were also observed (white arrow in F). (G and H) On diffusion tensor imaging (DTI), this mass appeared to compress the inferior frontal-occipital fasciculus (IFOF, G) and optic radiation (arrowheads in G and H) laterally and the pyramidal tract (curved arrow in H) medially.

Fig. 2

Macroscopic view: A 4 × 2 × 1 cm solid mass with pinkish surface color and multiple areas of necrosis and hemorrhage.

Fig. 3

(Microscopic view) A–C (Hematoxylin and eosin; × 100): Microscopic image: Spindle cells, with large nuclei and basophilic cytoplasm, suggesting a sarcomatous component, and multiple areas featuring large cells, with pleomorphic nuclei and a high mitotic rate (suggestive of a glial component); D–F (Immunohistochemical staining; × 400). Immunohistochemical imaging revealed glial fibrillary acidic protein (GFAP) staining in the glial cell cytoplasm (D), oligodendrocyte transcription factor 2 (OLIG2) staining in the glial cell nuclei (E), and smooth muscle actin (SMA) staining in the sarcomatous cell cytoplasm (F).