title: Case of clear cell ependymoma of medulla oblongata: clinicopathological and immunohistochemical study with literature review.
abstract: Clear cell ependymoma has been included in the WHO classification of the central nervous system in 1993, after the first report by Kawano et al. Since then, only a few cases have been reported. Most clear cell ependymoma cases reported in the literature so far were located in the supra-tentorial compartment and/or cerebellum, and one case was in the cervical spinal cord. We report a case of clear cell ependymoma whose histological features were sufficient for the diagnosis and was unusually located in the fourth ventricle originating from the medulla oblongata. The tumor showed uniform tumor cells with perinuclear halo, nuclei being centrally located. Most of the tumor cells were arranged as perivascular pseudorosettes, and no ependymal canals or rosettes were evident. Mitotic figures were not frequent. Immunohistochemically, the tumor cells were strongly reactive for glial fibrillary acidic protein and vimentin, and weak and dot-like positive for epithelial membrane antigen. Clear cell change of the tumor cells appeared to be fixation artifact because this feature was not evident in the frozen section.
authors.affiliation: Department of Pathology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan. vjamatya@mac.com
authors.forename: Vishwa Jeet
authors.initials: VJ
authors.lastname: Amatya
authors.forename: Yukio
authors.initials: Y
authors.lastname: Takeshima
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kaneko
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakano
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sugiyama
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kurisu
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Nakazato
authors.forename: Kouki
authors.initials: K
authors.lastname: Inai
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery; D004806:Ependymoma / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008526:Medulla Oblongata / Q000473:pathology* / Q000601:surgery; D009363:Neoplasm Proteins / Q000032:analysis; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins