[Adult T-cell leukemia with CD3 (-), CD4 (-) and CD8 (-)]

A case of an adult T-cell leukemia (ATL) with double negative (CD4-, CD8-) phenotype is reported. A-57-year-old man was consulted by his home doctor with us because of leucocytosis, splenomegaly and systemic lymphadenopathy. On admission, white blood cell count was 87,500/microliters with 77% of convoluted atypical cells. Serum anti-HTLV-1 antibody was positive and monoclonal insertion of HTLV-1 provirus into the atypical cell-gene was proved with southern blotting hybridization technique. A diagnosis of an ATL was made. Immunophenotypic analysis of leukemic cells showed CD3 (-), CD4 (-), CD8 (-) and genes encoding both TCR alpha and beta chains were rearranged. Though the patient responded to some degree to the combination chemotherapies including VEPA, he died of infectious complications about 4 months after admission.