title: Intracranial peripheral-type primitive neuroectodermal tumor.
abstract: A 15-year-old man presented with headache. Magnetic resonance (MR) imaging revealed a large extraaxial tumor with cyst at the right frontotemporal region. The solid part of the tumor was homogeneously enhanced on T(1)-weighted MR imaging after injection of gadolinium. Digital subtraction angiography of the external carotid artery revealed sunburst appearance corresponding to the tumor, which was fed by the right middle meningeal artery. His headache worsened and computed tomography revealed enlargement of the tumor and intracystic hemorrhage, so emergent operation was performed. At surgery, the tumor strongly adhered to the dural membrane, and was obviously extraaxial. The tumor and cyst were gross totally removed. The attachment site at the dura mater was resected. Histological examination showed solid growth of small round cells with uniform round nuclei and minimal cytoplasm. Immunohistochemical staining showed the cells were positive for MIC-2 (CD99). The MIB-1 labeling index was 53%. The histological diagnosis was peripheral-type primitive neuroectodermal tumor (pPNET). Following surgery, radiation therapy and chemotherapy were given. Ewing's sarcoma and pPNET form a family of small round cell tumors arising in the bone or soft tissue. MIC-2 is a useful marker in the differential diagnosis. Good prognosis may be attained if complete surgical excision of intracranial pPNET is achieved.
authors.affiliation: Department of Neurosurgery, Aomori Prefectural Central Hospital, Aomori, Japan. yfuruno@koto.kpu-m.ac.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Furuno
authors.forename: Shinjitsu
authors.initials: S
authors.lastname: Nishimura
authors.forename: Hironaga
authors.initials: H
authors.lastname: Kamiyama
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Numagami
authors.forename: Atsushi
authors.initials: A
authors.lastname: Saito
authors.forename: Mitsuomi
authors.initials: M
authors.lastname: Kaimori
authors.forename: Michiharu
authors.initials: M
authors.lastname: Nishijima
mesh_terms: D000071443:12E7 Antigen; D000293:Adolescent; D015703:Antigens, CD / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism; D001932:Brain Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D015815:Cell Adhesion Molecules / Q000378:metabolism; D003937:Diagnosis, Differential; D005625:Frontal Lobe / Q000473:pathology; D006261:Headache / Q000209:etiology / Q000473:pathology; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008579:Meningioma / Q000473:pathology* / Q000601:surgery; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D013702:Temporal Lobe / Q000473:pathology; D014057:Tomography, X-Ray Computed
chemical_list: D000071443:12E7 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; C061828:CD99 protein, human; D015815:Cell Adhesion Molecules; D019394:Ki-67 Antigen