Possibility of the diagnosis of subacute myeloid leukemia for a group of patients with trisomy 8: a report of 34 cases.

The term subacute myeloid leukemia is not present in most hematologic textbooks, but clinically the disease does exist. During the past 13 years, 34 patients with trisomy 8 (+8) and previous diagnoses of refractory anemia with excess blasts in myelodysplastic syndromes were followed and studied in our institute. None of the patients had been given cytotoxic drugs before the leukemia became apparent. Eighteen patients (52.9%) had a history of 3 months to more than 20 years before cytogenetic detection of +8. Abnormalities of blood cell counts were seen in 1 to 3 cell lines, with a median blast cell percentage in the bone marrow of 8% (range, 5%-19%). At a median follow-up period of 21.5 months (range, 3-129 months), the median overall survival time was 20 months for all of the patients with +8, including the patients with chromosome abnormalities in addition to +8. In the group with +8 only, 11 (45.8%) of the 24 patients developed frank leukemia, and 9 of these 11 patients died. In conclusion, our results showed that this group of +8 patients had multilineage abnormalities in blood cell counts and increased numbers of blasts in the bone marrow. The diseases of these patients manifested an insidious onset and a subacute but progressive clinical course, and they all had cytogenetic clonal changes with +8. These facts suggest that this group of +8 patients all had evidence of a leukemic clone, and their conditions might conform to the diagnosis of subacute myeloid leukemia.