Anaplastic large T-cell lymphoma in three black-tailed prairie dogs(Cynomys ludovicianus)

[摘要] Anaplastic large T-cell lymphoma (ALTCL) is rarely reported in domestic animals.Accordingly, the histopathological and immunohistochemical characteristics of ALTCL havenot been well established in prairie dogs. The present report documents three cases inwhich prairie dogs were diagnosed with ALTCL arising in the subcutaneous tissue, oralmucosa or the mesenteric lymph nodes. Of the three cases, one was available for necropsyand the others were biopsy cases. Microscopically, moderate to large, pleomorphicneoplastic lymphocytes with ovoid to polygonal, bizarre-shaped nuclei, abundant cytoplasmand eosinophilic granules were seen in all cases. Immunohistochemical staining revealedmembranous or cytoplasmic CD3 expression of the neoplastic lymphocytes. The neoplasticcells often had granzyme B-positive cytoplasmic granules. One of the prairie dogs withnodal ALTCL suffered systemic dissemination of the tumor and died suddenly. In the twobiopsy cases, one animal died on the day of the biopsy examination and the other died sixweeks after chemotherapy. ALTCL in prairie dogs displays a cytotoxic T cell phenotype andpresumably carries a poor prognosis regardless of the anatomical type.

[学科分类] 兽医学

[关键词] anaplastic large T-cell lymphoma;black-tailed prairie dog;granzyme B