Acute myeloid leukemia with marrow hypereosinophilia and chromosome 16 abnormality.

This article reports six cases of acute nonlymphocytic leukemia (ANLL) and an abnormal chromosome #16. All had the same hematologic pattern at diagnosis, i.e., peripheral blood hyperleukocytosis with a high percentage of monocytes and blast cells. The bone marrow showed three different cell populations: (a) myeloblasts, (b) monocytes and promonocytes, and (c) abnormal eosinophils. In three cases, an ultrastructural study confirmed the cytologic data. In all six cases, the diagnosis was acute myelomonocytic leukemia with bone marrow eosinophilia (M4-Eo). All cases showed an abnormal chromosome #16 in the bone marrow cells; in four cases, well-banded chromosomes were obtained, showing a pericentric inversion inv(16)(p13;q22). One patient had a 4-year remission, and another is still in remission 14 months after diagnosis. Three patients relapsed 7, 9, and 20 months after diagnosis. The last patient died soon after diagnosis. Thus, we do not support the hypothesis that patients with M4-Eo ANLL and chromosome #16 abnormality have a favorable prognosis.