Complex chromosomal abnormalities in a patient with refractory anemia with excess blasts (RAEB).

We report a new case of refractory anemia with excess blasts (RAEB) having complex chromosomal abnormalities. The 5q- associated with RAEB and other preleukemic syndromes was present in 100% of the cells; however, 60% of the cells had a highly unusual derivative chromosome involving the short arm of chromosome 1 and the long arm of chromosome 5, i.e., t(1;5)(p36;q14). Although the patient presented with highly complex chromosomal abnormalities, his initial clinical presentation was that of typical refractory anemia with excess blasts. Shortly after diagnosis (7 months), the patient developed acute leukemia.