title: Meningioma of the fourth ventricle.
abstract: Meningiomas are primary meningeal based tumors of the central nervous system that rarely are located strictly within the fourth ventricle. We report a 72-year-old man operated upon for such a tumor. The pre-operative magnetic resonance images revealed a well circumscribed mass in the fourth ventricle that exhibited a low signal on T1-weighted magnetic resonance images and homogenously enhanced with gadolinium. By light microscopy the tumor was composed of tightly packed spindle cells separated by collagen. Immunohistochemistry showed the tumor cells to be positive for vimentin and epithelial membrane antigen, and negative for glial fibrillary acidic protein. Electron microscopy revealed typical findings of meningioma, including interdigitating cell processes, desmosomes, and intermediate filaments. Although rare, fibroblastic meningioma must be included in the differential diagnosis of a fourth ventricular spindle cell tumor in elderly patients.
authors.affiliation: Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: T J
authors.initials: TJ
authors.lastname: Cummings
authors.forename: R C
authors.initials: RC
authors.lastname: Bentley
authors.forename: L
authors.initials: L
authors.lastname: Gray
authors.forename: W E
authors.initials: WE
authors.lastname: Check
authors.forename: T E
authors.initials: TE
authors.lastname: Lanier
authors.forename: R E
authors.initials: RE
authors.lastname: McLendon
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D002551:Cerebral Ventricle Neoplasms / Q000175:diagnosis* / Q000473:pathology; D020546:Fourth Ventricle; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008579:Meningioma / Q000175:diagnosis* / Q000473:pathology; D008854:Microscopy, Electron; D018396:Mucin-1 / Q000032:analysis; D014746:Vimentin / Q000032:analysis
chemical_list: D014408:Biomarkers, Tumor; D005904:Glial Fibrillary Acidic Protein; D018396:Mucin-1; D014746:Vimentin