A vestibular schwannoma (also known as acoustic neuroma, acoustic neurinoma, or acoustic neurilemoma) is a benign, usually slow-growing cerebellopontine angle tumor that develops from the balance and hearing nerves supplying the inner ear. The tumor comes from an overproduction of Schwann cells.
They usually originate in the internal acoustic meatus, and gradually extends into the cerebellopontine cistern. Invasive growth into the petrous bone is extremely rare. This may have arisen because of an unusually peripheral site of origin on the vestibular nerve 1).
Tumors are composed of Antoni A fibers (narrow elongated bipolar cells) and Antoni B fibers (loose reticulated). Verocay bodies are also seen, and consist of acellular eosinophilic areas surrounded by parallel arrangement of spindle shaped schwann cells (they are not a cell type).
Gao S et al., reported a cerebellar glioblastoma multiforme patient, with his clinical presentations and imaging characteristics mimicking a vestibular schwannoma. To the best of authors knowledge, this is the first reported patient with cGBM mimicking a vestibular schwannoma 2).