Hodgkin's-like lymphoma in a ferret (Mustela putorius furo).

A 7-year-old castrated male ferret developed unilateral cervical lymphadenomegaly over a 1-month period. Histological examination revealed proliferation of tumor cells in a diffuse and partially nodular pattern. The tumor cells were predominantly Hodgkin cells and binucleated Reed-Sternberg cells, characterized by abundant, clear, vacuolated cytoplasm, pleomorphic, ovoid nuclei with thick nuclear membranes and distinct nucleoli. Multinucleated cells, resembling lymphocytic and histiocytic (L&H) cells, were also observed. Immunohistochemically, the tumor cells expressed Pax-5, BLA-36 and vimentin. A small population of the tumor cells expressed CD20. This case showed proliferation of Hodgkin/Reed-Sternberg cells in conjunction with L&H cells that were histologically analogous to feline Hodgkin's-like lymphoma. However, Pax-5 and BLA-36 expression along with rare CD20 expression were consistent with classical Hodgkin's lymphoma in humans.