A unique case of intracranial collision tumor composed of ganglioglioma WHO gr I and supratentorial ependymoma WHO gr III: case-based literature review.

purposeIntracranial collision tumor is a rare entity that represents the coexistence of two histopathological different tumor types in the same area without histological admixture or an intermediate cell population zone. So far, several cases of collision tumors with ganglioglioma as its component have been reported in the literature, while supratentorial ependymoma has never been reported as a collision tumor component. We are presenting a unique case of collision tumor in patient without previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis. METHODS AND

resultsA 17-year-old male with no previous history of head trauma, neurological surgery, radiotherapy, or phakomatosis was presented to our clinic with grand mal seizure. Brain magnetic resonance imaging with gadolinium contrast was done revealing a contrast-enhancing lesion of right frontal lobe closely related to dura, surrounded by perifocal edema. The patient underwent a gross total tumor resection. Histological examination revealed collision tumor with two distinct components: ganglioglioma and supratentorial ependymoma.

conclusionTo our best knowledge, no previous reports of collision tumor composed of ganglioglioma and supratentorial ependymoma in a single patient have been reported. We believe that this report could significantly contribute to further surgical practice as well as to treatment decision for these types of collision tumors.