Cyclic neutropenia as a premalignant manifestation of acute lymphoblastic leukemia.

A 20-year-old female from the Philippines developed anemia and granulocytopenia. With androgen therapy, her anemia improved but she continued to show a pattern of fluctuating neutropenia consistent with human cyclic neutropenia: Blood neutrophil oscillation was regular with a periodicity of 21 days. She developed recurrent pharyngitis and apthous stomatitis but there was no cycling of other blood elements. Bone marrow aspiration and biopsy showed normal developing myeloid cells, a clonal chromosomal abnormality, and myelofibrosis. During the fourth documented cycle, blasts appeared and complete lymphoblastic transformation ensued. Blast cells were CALLA positive, Ia positive, and contained intranuclear TdT; they were negative for E, EAC, and EA rosettes. She was treated for non-T, non-B CALLA-positive ALL and within 6 weeks was in a remission without evidence of cycling neutrophil counts. This young woman's case suggests that cyclic neutropenia may represent a previously unrecognized premalignant state associated with acute lymphoblastic leukemia.