Association of an Inversion of Chromosome 16 with Abnormal Marrow Eosinophils in Acute Myelomonocytic Leukemia

TLDR

The study identified 18 patients with inv(16)(p13q22) among 308 newly diagnosed acute non‑lymphocytic leukemia cases. All 18 patients had acute myelomonocytic leukemia with abnormal eosinophils, and every patient with such eosinophils carried inv(16); the subgroup showed a favorable prognosis, with 13 of 17 treated patients achieving complete remission and 10 remaining in first remission. Published in N Engl J Med 1983; 309:630–6.

Abstract

We identified 18 patients with an inversion of chromosome 16, inv(16)(p13q22), among 308 patients with newly diagnosed acute nonlymphocytic leukemia. Each of these 18 patients had acute myelomonocytic leukemia (M4 subtype) and eosinophils with distinctly abnormal morphology, cytochemical staining, and ultrastructure. These eosinophils constituted from 1 to 33 per cent of the nucleated marrow cells. In our series, every patient with acute myelomonocytic leukemia and abnormal eosinophils also had an abnormal chromosome 16. This subgroup of M4 patients had a good response to intensive therapy designed to induce remission; 13 of 17 treated patients entered a complete remission, and 10 remain in first remission. Thus, patients with an inversion of chromosome 16 appear to represent a unique cytogenetic–clinicopathological subtype of acute nonlymphocytic leukemia with a favorable prognosis. (N Engl J Med 1983; 309:630–6.)