title: Pilocytic astrocytoma in a cat.
abstract: A 12-year-old crossbred female cat was presented for necropsy with a history of anorexia, ataxia, convulsions, and blindness. Grossly, a whitish, firm, and well-circumscribed nodule with an irregular surface of approximately 1.5 cm in diameter was observed in the right dorsal, parietal, and occipital lobes of the brain. Histologically, the tumor was composed of neoplastic astrocytes forming irregular interweaving sheets and bundles. These cells were elongated, spindle-shaped, and bipolar, and some had clear cytoplasm and a dense nuclear chromatin pattern. Extensive areas of cartilaginous and osseous metaplasia were observed. By immunohistochemistry, the neoplastic cells were found to be markedly positive for S-100 protein and glial fibrillary acidic protein. On the basis of morphologic and immunohistochemical features, the diagnosis of pilocytic astrocytoma was made.
authors.affiliation: Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária da Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. santanafjf@yahoo.com
authors.forename: F J F
authors.initials: FJ
authors.lastname: Sant'Ana
authors.forename: R
authors.initials: R
authors.lastname: Serakides
authors.forename: D L
authors.initials: DL
authors.lastname: Graça
mesh_terms: D000818:Animals; D001254:Astrocytoma / Q000473:pathology / Q000662:veterinary*; D001932:Brain Neoplasms / Q000473:pathology / Q000662:veterinary*; D002371:Cat Diseases / Q000473:pathology*; D002415:Cats; D017809:Fatal Outcome; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry / Q000662:veterinary; D009418:S100 Proteins / Q000378:metabolism
chemical_list: D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins