Only retrospectively, using RT-PCR, did we detect the acute myeloid leukemia subset-specific fusion gene AML1/ETO in the frozen samples of the relapsed tumor, as well as in the otherwise unaffected bone marrow and peripheral blood (representing 'minimal initial disease' in the latter two samples).     ///    Aleukemic granulocytic sarcoma with AML1/ETO fusion gene expression and clonal T cell populations.. 