Adult T-cell leukemia: a report on two white patients.

Two white European males are reported with adult T-cell leukemia (ATL), a disease first described in Japan, but recently also in the U.K. and U.S.A. Both patients presented with lymphadenopathy, but without a mediastinal mass. In addition, one patient had skin infiltrates and the other had hepatosplenomegaly. Morphologic and ultrastructural examination of the blasts in bone marrow and lymph node biopsy revealed a predominance of polymorphic lymphoid cells with pronounced nuclear irregularities and a semi-mature chromatine pattern. Histopathology of the lymph nodes showed a diffuse infiltration with medium-sized lymphoblasts with irregular nuclei. The blasts in the bone marrow formed E rosettes with sheep erythrocytes, lacked terminal deoxynucleotidyl transferase (Tdt) activity but expressed the Ia-like antigen; although the majority of the cells reacted with a polyclonal anti-T-cell serum, they were negative for OKT3. In one patient a helper/inducer phenotype (OKT4+) was found in the lymphoblasts of bone marrow and lymph node, while in the other only in the lymph node. The difference between bone marrow and lymph node phenotype is discussed. To our knowledge, these are the first two European patients reported with ATL, a disease clearly different from convoluted T-cell acute lymphocytic leukemia.