title: Cutaneous Epitheliotropic T-Cell Lymphoma in a Marsh Rice Rat (Oryzomys palustris).
abstract: Published reports of spontaneous neoplasia in marsh rice rats (Oryzomys palustris) are sparse. We report here a case of cutaneous epitheliotropic T-cell lymphoma in a 14-mo-old marsh rice rat that involved the ear pinnae, with dissemination to the liver and spleen. Histologically, the thickened ear pinnae showed diffuse infiltration of neoplastic lymphocytes into the epidermis, dermis, and adnexal skin structures, with Pautrier microaggregations present in the epidermis. In addition, neoplastic lymphocytes were observed infiltrating and disrupting the architecture of the liver and spleen. Neoplastic lymphocytes were strongly positive for the T-cell marker CD3 but were negative for the B-cell markers CD19 and CD20. These histologic and immunohistochemical features are consistent with an epitheliotropic T-cell lymphoma, as previously reported in other species, including humans. To our knowledge, this report represents the first published case of spontaneous cutaneous epitheliotropic T-cell lymphoma in a marsh rice rat.
authors.affiliation: Animal Care Services, University of Florida, Gainesville, Florida, USA. taylorb2@ufl.edu.
authors.forename: Bryan F
authors.initials: BF
authors.lastname: Taylor
authors.affiliation: Division of Laboratory Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Bekkevold
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, Florida, USA.
authors.forename: J Ignacio
authors.initials: JI
authors.lastname: Aguirre
authors.affiliation: Animal Care Services, University of Florida, Gainesville, Florida, USA.
authors.forename: Karl
authors.initials: K
authors.lastname: Andrutis
authors.affiliation: Animal Care Services, University of Florida, Gainesville, Florida, USA.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Reinhard
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy / Q000662:veterinary; D054644:Ear Auricle / Q000737:chemistry / Q000473:pathology*; D004428:Ear Neoplasms / Q000737:chemistry / Q000473:pathology / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D016246:Lymphocytes, Tumor-Infiltrating / Q000737:chemistry / Q000473:pathology; D016410:Lymphoma, T-Cell, Cutaneous / Q000737:chemistry / Q000473:pathology / Q000662:veterinary*; D008297:Male; D016205:Sigmodontinae; D012878:Skin Neoplasms / Q000737:chemistry / Q000473:pathology / Q000662:veterinary*
chemical_list: D014408:Biomarkers, Tumor