title: Malignant peripheral nerve sheath tumor of the trigeminal nerve: clinicopathologic features in a young adult patient.
abstract: Malignant peripheral nerve sheath tumors (MPNSTs) arising from cranial nerves are rare and usually affect adults. Here we report the clinicopathologic features of a young adult patient with a trigeminal nerve MPNST, in whom another tumor involving the oculomotor nerve on the contralateral side was evident. The patient, an 18-year-old woman, had suffered recurrent paroxysmal sharp stabbing pain over her cheek and forehead on the right side for 1 month. A brain MRI study disclosed a mass, 35 mm in diameter, in the right Meckel's cave, and another mass, 10 mm in diameter, involving the intracranial portion of the left oculomotor nerve. Following gadolinium administration, the former and latter tumors exhibited strong and weak enhancement, respectively. The patient had no clinical stigmata characteristic of neurofibromatosis type 1. Following a tentative diagnosis of schwannoma, total resection of the trigeminal nerve tumor was performed. Histologically, the tumor consisted of highly cellular, spindle-shaped cells arranged in a fascicular pattern, with occasional mitotic figures, nuclear pleomorphism and necrosis. Immunohistochemically, the tumor cells showed variable intensities and frequencies of reactivity for S-100 protein, myelin basic protein, CD34, podoplanin and p53, but no reactivity for Smarcb1. Thus, the tumor exhibited features of MPNST. This case appears to provide information that is useful for accurate diagnosis and surgical planning in patients with bilateral or multiple cranial nerve tumors.
authors.affiliation: Department of Neurosurgery, Nagaoka Red Cross Hospital, Nagaoka, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakayama
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Watanabe
authors.forename: Kenji
authors.initials: K
authors.lastname: Suzuki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Usuda
authors.forename: Iwao
authors.initials: I
authors.lastname: Emura
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Ogura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shiga
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Toyoshima
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Kakita
mesh_terms: D000293:Adolescent; D003390:Cranial Nerve Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D009442:Neurilemmoma / Q000473:pathology*; D020433:Trigeminal Nerve Diseases / Q000473:pathology*
keywords: brain tumor; gadolinium enhancement; oculomotor nerve schwannoma; p53; pathology; smarcb1