[Erythroblastic transformation of chronic myelogenous leukemia associated with an additional chromosome abnormality translocation (6;9].

A 57-year-old female was diagnosed being in the blastic phase of chronic myelogenous leukemia (CML) on her second admission in May 1993. The patient was previously treated with vincristine and prednisolone in the accelerated phase of CML in December 1991 without improvement. Other chemotherapeutic agents such as BHAC-DMP (enocitabine, daunorubicin, mercaptopurine, prednisolone), interferon, mercaptopurine and ranimustine were also administered. After the second chronic phase was achieved, she was treated with busulfan as an outpatient. On her second admission, the diagnosis of erythroblastic transformation was made, and cytogenetic study revealed t(9;22) (q34;q11) with the additional chromosomal abnormalities, t(6;9) (p23;q34). This karyotype rearrangement has been reported neither in Ph-positive CML nor in blastic crisis.