Flow cytometry for the diagnosis of lymphoma in canines

Abstract

Canine lymphoma is a malignant tumor that represents 7 to 24% of all malignancies and 80% of hematopoietic tumors. In humans and canines, 80-85% of lymphomas originate from neoplastic B-lymphocytes (B-cell lymphoma) and 15 to 20% are lymphomas generated from T lymphocytes. The latter are generally more aggressive, have shorter survival time and may need differential therapy. For this reason, knowing the tumor immunophenotype (origin of the tumor) allows establishing a more accurate prognosis and treatment appropriate to the type of tumor. In this context, immunophenotyping by flow cytometry performed from a lymph node puncture is a tool of great diagnostic value for the veterinary clinic. The aim of this work was to present two clinical cases of canines with a clinical and cytological diagnosis of lymphoma, which underwent flow cytometry to determine the cellular origin of the neoplasm, as well as complementary studies to determine local and systemic repercussions of the tumor process. The result of the immunophenotyping evidenced the presence of a CD4 + T-cell lymphoma in one of the patients and B-cell lymphoma in the other. At the systemic level, the patient with T-cell lymphoma presented neutrophilic leukocytosis and hypercalcemia, while in both patients increases of lactate dehydrogenase enzyme levels were observed. Based on these results, it is discussed how through the tumor immunophenotyping, it is possible to deepen in the diagnosis, to give an accurate prognosis and provide to the treating clinician a value information helping them in their therapeutic decisions.