Chronic myelomonocytic leukemia: clinical features, cytogenetics, and prognosis in 30 consecutive cases.

A retrospective analysis of 30 patients with chronic myelomonocytic leukemia (CrMML) was performed to define the natural history of the disease and the risk of acute transformation. Our patients fulfilled the following criteria of diagnosis: blood monocytosis over 1 X 10(9)/l, blast cell percentage in bone marrow up to 30, and in peripheral blood less than 5. The most common presenting feature was anemia; seven patients had fever; three patients complained of purpura and bleeding. Anysopoikilocytosis and macrocytosis were frequent. Abnormal granulocyte morphology, defective granulation and abnormal leukocyte alkaline phosphatase were often observed. Blast cells in peripheral blood smears were found in 14 patients. Serum and urine lysozyme levels were increased in 82 per cent and 93 per cent, respectively. Dysplastic changes involving erythroid, granulocytic and megakaryocytic lineages were constant features in all cases. Agranulated blasts above 5 per cent of marrow nucleated cells were seen in 13 patients (43 per cent). Seven of the 20 patients showed non-specific chromosomal abnormalities at diagnosis. Median survival from diagnosis was 18 months (range, 3-112). Evolution into acute myeloid leukemia occurred in 11 patients. No difference in survival was found between patients who developed acute leukemia and patients who did not. A shorter survival has correlated to the following parameters: leukocytes greater than 10 X 10(9)/l, the presence of blasts in peripheral blood and agranulated blasts in the marrow above 5 per cent.