title: Hyperostotic meningioma with minimal tumor invasion into the skull.
abstract: A 56-year-old man presented with a meningioma associated with hyperostotic bone containing little tumor cell infiltration. The patient presented with a growing mass on his right forehead and exophthalmos. Computed tomography (CT) taken 4 years previously revealed only hyperostosis without intracranial lesion. Repeat CT revealed an enhanced intracranial mass with overlying diffuse hyperostosis extending extracranially. The tumor and affected bone were widely removed. Histological examination confirmed rhabdoid meningioma in the intracranial and extracranial lesion. However, most of the hyperostotic bone showed no tumor cell infiltration. The cause of hyperostosis associated with meningioma is unclear, but tumor invasion is the generally accepted cause. In this case, hyperostosis occurred without tumor cell infiltration so another mechanism was probably involved. The extracranial extension occurred despite the disproportionately small tumor without global tumor cell infiltration of the bone or bony erosion.
authors.affiliation: Department of Neurosurgery, College of Medicine, Korea University, Seoul, R.O.K.
authors.forename: Jun-Hong
authors.initials: JH
authors.lastname: Min
authors.forename: Shin-Hyuk
authors.initials: SH
authors.lastname: Kang
authors.forename: Jang-Bo
authors.initials: JB
authors.lastname: Lee
authors.forename: Yong-Gu
authors.initials: YG
authors.lastname: Chung
authors.forename: Hoon-Kap
authors.initials: HK
authors.lastname: Lee
mesh_terms: D006801:Humans; D015576:Hyperostosis / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000473:pathology*; D008579:Meningioma / Q000150:complications* / Q000175:diagnosis / Q000473:pathology*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging / Q000473:pathology; D012886:Skull / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed