title: Chordoid glioma of the third ventricle: a report of two cases, one with ultrastructural findings.
abstract: Chordoid glioma, which generally occurs in adults, is a rare CNS tumor arising in the anterior part of the third ventricle. We report two cases of chordoid glioma of the third ventricle in a 42-year-old woman and a 51-year-old man, respectively. Both tumors showed essentially the same histological and immunohistochemical features; the tumors were composed of cords and nests of epithelioid, GFAP-immunoreactive cells in a mucinous stroma with lymphoplasmacytic infiltrates at the tumor periphery. Ultrastructural examination in one case revealed that the tumor cells were characterized by the presence of hemidesmosomes and associated focal basal lamina formation, intermediate junctions, microvilli and cilia, and intercellular microrosettes with microvilli. Of interest was that small blood vessels with fenestrated endothelial cells were present in the stroma. In the brain, the presence of fenestrated endothelial cells is a feature of the circumventricular organs (except the subcommissural organ), among which the organum vasculosum of the lamina terminalis is located in the anterior part of the third ventricular floor that is lined by specialized ependymal cells known as tanycytes. These findings further strengthen the hypothesis that chordoid glioma may represent a peculiar clinicopathological subtype of ependymoma (chordoid ependymoma) originating from the lamina terminalis area.
authors.affiliation: Department of Neurosugery, Toyoma Prefectural Central Hospital, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kawasaki
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kohno
authors.forename: Chikanori
authors.initials: C
authors.lastname: Inenaga
authors.forename: Akihiko
authors.initials: A
authors.lastname: Sato
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hondo
authors.forename: Atsuo
authors.initials: A
authors.lastname: Miwa
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Fujii
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D000328:Adult; D001485:Basement Membrane / Q000473:pathology; D001808:Blood Vessels / Q000473:pathology; D002551:Cerebral Ventricle Neoplasms / Q000098:blood supply / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D002923:Cilia / Q000473:pathology; D042783:Endothelial Cells / Q000473:pathology; D004806:Ependymoma / Q000473:pathology; D015622:Epithelioid Cells / Q000473:pathology; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D005910:Glioma / Q000098:blood supply / Q000737:chemistry / Q000473:pathology* / Q000648:ultrastructure; D022002:Hemidesmosomes / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008854:Microscopy, Electron; D008871:Microvilli / Q000473:pathology; D008875:Middle Aged; D020542:Third Ventricle; D014057:Tomography, X-Ray Computed
chemical_list: D005904:Glial Fibrillary Acidic Protein