title: A comparative pathological study on granulomatous meningoencephalomyelitis and central malignant histiocytosis in dogs.
abstract: Histiocytic proliferative disorders in canine central nervous system (CNS) including granulomatous meningoencephalomyelitis (GME) and malignant histiocytosis were compared pathologically. Lesions of GME mainly existed in the white matter of the cerebrum, brainstem and cerebellum and consisted of characteristic perivascular cuffing, parenchymal granuloma and leptomeningeal infiltrates of mononuclear cells. In malignant histiocytosis, there were two histological patterns, diffuse proliferation of neoplastic histiocytes through the leptomeninges and neoplastic nodule formation in the parenchyma. Neoplastic histiocytes exhibited mild to severe cellular atypia and high ability of invasion into the brain parenchyma. Mitotic and phagocytic figures were also observed. Several histiocytic markers, including lysozyme, alpha1-antitrypsin and lectin RCA-1, revealed histiocytic origin of both inflammatory and neoplastic cells, however, those were not determinative for the discrimination between GME and malignant histiocytosis. CD3- and PCNA-positive cells existed in the lesions of both diseases. The number of CD3-positive cells in GME tended to be greater than in malignant histiocytosis, while the difference was not statistically significant.
authors.affiliation: Department of Veterinary Pathology, Faculty of Agriculture, Miyazaki University, Miyazaki, Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Suzuki
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Uchida
authors.forename: Motoji
authors.initials: M
authors.lastname: Morozumi
authors.forename: Tokuma
authors.initials: T
authors.lastname: Yanai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakayama
authors.forename: Ryoji
authors.initials: R
authors.lastname: Yamaguchi
authors.forename: Susumu
authors.initials: S
authors.lastname: Tateyama
mesh_terms: D000818:Animals; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D004679:Encephalomyelitis / Q000473:pathology / Q000662:veterinary*; D005065:Euthanasia; D005260:Female; D054747:Histiocytic Sarcoma / Q000473:pathology / Q000662:veterinary*; D008297:Male; D008590:Meningoencephalitis / Q000473:pathology / Q000662:veterinary*