Intraventricular Epithelioid Glioblastoma: A Case Report.

BACKGROUND: Epithelioid glioblastoma, a high-grade, diffuse astrocytic tumor variant, comprises closely packed epithelioid cells and rhabdoid cells. This rare tumor usually develops in the cerebral cortex and diencephalon; however, in the case reported here, it was located intraventricularly.

CASE DESCRIPTION: A 47-year-old woman was referred to our hospital with a right intraventricular mass that had rapidly increased in size. On discovery of the tumor 3 years earlier at the referring hospital, the mass was small, calcified, and attached to the periventricular parenchyma. Over the next 2 years, the mass grew slowly, as observed on periodic magnetic resonance imaging scans. Forty days before the referral, the patient experienced headache and nausea, and marked growth and intratumoral hemorrhage were visible on a computed tomography scan of the head. The tumor was partially removed via a superior parietal lobule corticotomy. Histopathological examination confirmed an isocitrate dehydrogenase-wild-type epithelioid glioblastoma with a BRAF V600E mutation, but the original slow-growing lesion was no longer detected. Consequently, we assume that in this case, a low-grade glioma transformed into an aggressively malignant epithelioid glioblastoma.

CONCLUSIONS: We present the first case of an intraventricular epithelioid glioblastoma that might have arisen from a low-grade glioma with calcification. We recommend including this tumor variant in the differential diagnosis of lateral ventricle tumors.