2017 Volume 26 Issue 2 Pages 86-90
An 11 - year - old mongrel dog was recognized to have a remarkable increase in peripheral blood lymphocytes and an enlargement of the superficial lymph nodes. In the peripheral blood smear examination, a remarkable increase in small lymphocytes was observed. On examination of the bone marrow, the small lymphocytes occupied most of the nucleated cells. Results of an analysis of antigen receptor rearrangement using polymerase chain reaction of the peripheral blood showed a clonal expansion of B cells. Thus, a diagnosis of B cell chronic lymphocytic leukemia was made. Middle-sized lymphocytes were uniformly observed in the aspirate of a needle biopsy of the popliteal and the inguinal lymph nodes and spleen. Findings of the histopathological examination were consistent with a poorly differentiated lymphoma. In addition, these lymphocytes were diagnosed as diffuse large B-cell lymphoma because CD20 was diffusely positive and CD3 was negative on immunohistochemical staining. The case had positive outcomes with the UW25 protocol. After completion of the protocol, there was no recurrence and the disease has been benign as of day 1270.
