Jugular foramen chordoid meningioma.

Chordoid meningioma (CM) is a rare histological variant of meningioma and is classified as an atypical meningioma on pattern alone. Herein is described the first case of CM occurring in the jugular foramen. The patient was a 45-year-old woman with a 2 year history of progressive right hearing loss. Magnetic resonance imaging (MRI) demonstrated a large, dumbbell-shaped, homogenously gadolinium-enhanced mass in the right jugular foramen, extending medially to the cerebellopontine angle and caudally into the upper carotid space. Angiographic findings supported a diagnosis of schwannoma. Intraoperatively, the tumor appeared to involve the right glossopharyngeal nerve completely and the vagus nerve incompletely, and was incompletely resected. Microscopically, the tumor consisted predominantly of cords and nests of medium-sized cells with bland cytological features, surrounded by a pale basophilic mucin. Immunohistochemically, the tumor cells demonstrated reactivity for epithelial membrane antigen (membranous) and vimentin, with negative staining for S-100 protein, cytokeratin, CD34, glial fibrillary acidic protein (GFAP), synaptophysin, and chromogranin A. Based on the chordoid histology, an organoid lobular arrangement of the tumor cells, and the location of the tumor (jugular foramen), the differential diagnosis included not only a chordoma but also a paraganglioma (glomus jugulare tumor). Histological identification of typical meningotheliomatous areas, plus selective immunohistochemical panel, is important to establish the correct diagnosis.