[Adult T-cell leukemia/lymphoma with OKT4 lack of OKT8 in peripheral blood and with OKT4 and OKT8 in lymph node. Study of two color flow cytometry].

Adult T-cell leukemia (ATL) cells usually express the helper/inducer associated antigen OKT 4 with lack of OKT8. However, there are a few case reports indicating that there are atypical cell phenotypes in ATL including OKT4+/OKT8+. The analysis of surface phenotype of peripheral lymphocytes and abnormal cells in lymph node was done with monoclonal antibodies. ATL cells of peripheral blood and small lymphocytes of lymph node had the usual phenotype, OKT4+/OKT8-, but neoplastic cells of large lymphocytes of lymph node had the unusual phenotype OKT4+/OKT8+. The neoplastic cells were immunophenotyped by two-color flow cytometry analysis. OKT4+/OKT8- cells had a helper cell phenotype. OKT4+/OKT8+ cells had a helper cell and a cytotoxic cell. These findings suggest that in this case ATL cells arise from common thymocyte and one of them mature in peripheral blood other remain in lymph node.