Highly Complex Chromosomal Rearrangement of Chromosome 9 in a Case of Chronic Myeloid Leukemia

A 63-year-old man with chronic myeloid leukemia (CML) was found to have a new complex Philadelphia translocation. All of the bone marrow cells had a rearrangement of a five-way translocation, t(9;22;10;12;1), involving a single chromosome 9. The patient went into blast crisis two years after initial diagnosis and the karyotype remained unchanged. He died in blast crisis 10 months later. We believe this case is a unique 5-way translocation in which four chromosomes were translocated to a single chromosome.