Multicentric lymphoma in a male Labrador retriever dog

Multicentric lymphoma (grade V) was diagnosed in a 7-year-old dog with listlessness, excessive panting and generalized lymphadenopathy. Hematological examination showed reduced RBC and platelet count and severe increase in leukocyte count with 90% of lymphocytes and 10% of neutrophils. Radiographic examination showed soft tissue masses (sublumbar lymph nodes) in caudal abdomen and mild liver enlargement. Prostate gland and spleen were also enlarged. There were no other abnormalities in abdominal and thoracic radiography, and metastatic mass couldn't be found in the lungs. Histopathological examination of the right popliteal lymph node showed large neoplastic lymphoblasts, and the immunophenotype of the tumor showed B-cell origin with CD3 and CD20 expression. Treatment with systemic chemotherapy was initiated in an attempt to induce remission using cyclophosphamide, vincristine, and prednisolon (COP) in doses recommended in the literature. Currently, the patient is clinically doing very well with a good appetite, adequate weight gain, increased activity level, decreased lymph node size, and return to normal attitude. © 2010 Springer-Verlag London Limited.