title: Malignant pilomatricoma in a dog.
abstract: An 11-year-old female German shepherd dog was presented with a history of lameness and pain in the left forelimb. Clinical examination revealed ataxia of the hindlimbs and a subcutaneous mass in the left prescapular region. Radiography revealed metastatic foci in the left humerus, lung and abdomen. Gross necropsy examination revealed a firm, white mass in the left prescapular region. Multiple nodules with similar characteristics were observed in the lung, liver and spleen. Bone lysis was noted in the humerus and the fifth to seventh lumbar vertebrae. Microscopical examination revealed a proliferation of basal cells forming irregular islands of various sizes and surrounding extensive zones of keratinized 'ghost' cells. A definitive diagnosis of malignant pilomatricoma was made. This is a rare tumour in dogs with no previous report of metastasis to the spleen and liver.
authors.affiliation: Laboratory of Animal Pathology, Universidade Estadual de Londrina, Londrina-PR, Brazil. elivet02@gmail.com
authors.forename: E O
authors.initials: EO
authors.lastname: da Silva
authors.forename: K T
authors.initials: KT
authors.lastname: Green
authors.forename: D G
authors.initials: DG
authors.lastname: Wasques
authors.forename: R O
authors.initials: RO
authors.lastname: Chaves
authors.forename: A C Faria
authors.initials: AC
authors.lastname: dos Reis
authors.forename: A P F R L
authors.initials: AP
authors.lastname: Bracarense
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000556:secondary / Q000662:veterinary; D002280:Basal Cell Carcinoma / Q000175:diagnosis / Q000662:veterinary; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D005260:Female; D006201:Hair Diseases / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D006811:Humerus / Q000473:pathology; D008159:Lumbar Vertebrae / Q000473:pathology; D018296:Pilomatrixoma / Q000556:secondary / Q000662:veterinary*; D012878:Skin Neoplasms / Q000473:pathology / Q000662:veterinary*