Immunohistochemical Characterization of Canine Lymphomas

Lymphomas occur by clonal expansion of lymphoid cells and have distinctive morphological and immunophenotypic features. Determination of canine lymphoma immunophenotype is useful for accurate prognosis and further therapy. In the suggested study, we performed an immunohistochemical evaluation of some cases with canine lymphoma diagnosed in the Department of Pathology (Faculty of Veterinary Medicine, Cluj-Napoca, Romania), in order to characterize them. The investigation included 39 dogs diagnosed with different anatomical forms of lymphoma, following necropsy analysis or assessment of biopsies. The diagnosis of lymphoma was confirmed by necropsy and histopathology (Hematoxylin-eosin stain) examinations. The collected specimens were analyzed by immunohistochemistry technique (automatic method) using the following antibodies: CD3, CD20, CD21 and CD79a. The analyzed neoplasms were characterized as follows: about 64.10% of cases were diagnosed as B-cell lymphomas, 33.34% of cases as T-cell lymphomas, whereas 2.56% of cases were null cell type lymphomas (neither B nor T). Most of multicentric (80%), mediastinal (60%) and primary central nervous system lymphomas (100%) had B immunophenotype, while the majority of cutaneous (80%) and digestive (100%) lymphomas had T immunophenotype. Immunohistochemical description of canine lymphomas can deliver some major details concerning their behavior and malignancy. Additionally, vital prognosis and efficacy of some therapeutic protocols are relying on the immunohistochemical features of canine lymphoma.