[Chronic myelocytic leukemia following chemotherapy of acute promyelocytic leukemia].

Ph1-positive chronic myelocytic leukemia (CML) developing in a treated case of acute promyelocytic leukemia (APL) is reported. The patient was a 62-year-old male who was diagnosed as having APL in December 1978. He was treated with daunorubicin, Ara-C and 6MP and a complete remission was obtained 4 months later. But APL recurred in February 1981. He was treated with BHAC, aclarubicin, 6MP and prednisolone. He remained in continuous complete remission for 5 years, when all therapy was discontinued. After then, the leukocytes count continued to rise and a diagnosis of Ph1-positive CML was made in September 1986. His leukocytes count has been well controlled with the use of busulfan. The event in this case suggests a possibility of the Ph1-positive CML being a secondary disease related to prior long term chemotherapy.