title: Immature T cell neoplasms in three young cattle.
abstract: Immature T cell neoplasms in three young Holstein cattle with neoplastic involvement of the thymus are described. Case 1, with a precursor T lymphoblastic leukemia (calf form of leukosis), was an 86-day-old female calf. The leukemia was characterized by replacement of the bone marrow and spleen by leukemia cells, but preservation of epithelial frameworks throughout the thymus. The other two neoplasms were thymic γδ T cell lymphomas, which were observed in a 246-day-old steer (case 2) and a 16-month-old heifer (case 3). Histological examination revealed obliteration of the normal thymic architecture and stromal fibrosis, with the spleen and liver far less severely affected than in case 1. There were cytological differences bewteen the tumors in case 1 and cases 2 and 3. Additionally, WC1 and CD8 were expressed only in the latter. Thus, the leukemia and these lymphomas should be regarded as independent disease entities on the basis of histological and immunohistochemical characteristics.
authors.affiliation: Toyama Prefectural Tobu Livestock Hygiene Service Center, 46 Mizuhashikanaoshin, Toyama 939-3548, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Yokota
authors.forename: Kenshi
authors.initials: K
authors.lastname: Sato
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Wada
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Koichi
authors.initials: K
authors.lastname: Kadota
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D005260:Female; D008223:Lymphoma / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000473:pathology / Q000662:veterinary*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism*; D013953:Thymus Neoplasms / Q000473:pathology / Q000662:veterinary*
chemical_list: D016692:Receptors, Antigen, T-Cell, gamma-delta