Trisomy 6 as the sole chromosome abnormality in myeloid disorders.

Trisomy 6 was the sole chromosomal abnormality detected in two patients with myeloid disorders in relapse. One had a refractory anemia with excess of blasts and the other acute myeloblastic leukemia. Simple trisomy 6 has been reported in patients with myeloid disorders, marrow hypoplasia, acute myeloid leukemia, and "preleukemia." The prognostic significance of this nonrandom chromosomal abnormality is discussed.