title: A collision tumour consisting of malignant trichoblastoma and melanosarcoma in a rabbit.
abstract: A 7-year-old mixed breed neutered female rabbit (Orytolagus cuniculus) developed a solitary black nodular mass (1 cm in diameter) in the skin of the right flank. Microscopically, the mass consisted of an admixture of neoplastic trichoblasts and melanocytes. The former were arranged as solid, trabecular, island-like and gland-like structures and the cells had oval nuclei with prominent nucleoli and lightly eosinophilic scant cytoplasm. The latter population exhibited prominent nuclear atypia and high mitotic index in the clusters of a few cells or single cells. Immunohistochemically, the neoplastic trichoblasts expressed cytokeratins and E-cadherin, while the neoplastic melanocytes expressed vimentin, S100 protein, melan-A and melanoma antigen. A diagnosis of collision tumour involving malignant trichoblastoma and melanosarcoma was made.
authors.affiliation: Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano City, Osaka 598-8531, Japan.
authors.forename: H M
authors.initials: HM
authors.lastname: Golbar
authors.affiliation: Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano City, Osaka 598-8531, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Izawa
authors.affiliation: Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano City, Osaka 598-8531, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kuwamura
authors.affiliation: Kitasuma Animal Hospital, 9-5-8 Yokoo, Suma Ward, Kobe City, Hyogo 654-0131, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Fujita
authors.affiliation: Kitasuma Animal Hospital, 9-5-8 Yokoo, Suma Ward, Kobe City, Hyogo 654-0131, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sasai
authors.affiliation: Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano City, Osaka 598-8531, Japan. Electronic address: yamate@vet.osakafu-u.ac.jp.
authors.forename: J
authors.initials: J
authors.lastname: Yamate
mesh_terms: D000818:Animals; D005260:Female; D006201:Hair Diseases / Q000473:pathology / Q000662:veterinary*; D008545:Melanoma / Q000473:pathology / Q000662:veterinary*; D018193:Neoplasms, Complex and Mixed / Q000473:pathology / Q000662:veterinary*; D011817:Rabbits; D012878:Skin Neoplasms / Q000473:pathology / Q000662:veterinary*
keywords: collision tumour; malignant trichoblastoma; melanosarcoma; rabbit