Characterization of lymphocyte populations by flow cytometry in a calf with sporadic juvenile lymphoma.

A 2-month-old Angus heifer was presented to Washington State University Veterinary Teaching Hospital for generalized peripheral lymphadenopathy and mild anorexia. Results of a CBC revealed marked lymphocytosis consisting primarily of large, atypical lymphocytes with cleaved, reniform nuclei. A presumptive diagnosis of sporadic juvenile lymphoma was made. To confirm these findings, a prescapular lymph node was submitted for histopathology, immunochemistry, and flow cytometric analysis. Peripheral blood also was analyzed by flow cytometry. Phenotypic characterization of lymph node and peripheral blood cell populations verified the calf had the B-cell form of sporadic juvenile lymphoma. The results of this investigation expand the phenotypic characterization of neoplastic lymphocytes in sporadic juvenile lymphoma.