[Therapy-related acute promyelocytic leukemia with a t(9;22)(q34;q11) and t(15;17)(q22;q11 to approximately 12) subclone].

The translocation (15;17) is a typical marker of acute promyelocytic leukemia, whereas t(9;22) is predominantly associated with chronic myelogenous leukemia, and seldom with acute myelogenous leukemia. Furthermore, the association between t(15;17) and t(9;22) in the same cell is extremely rare. We present a case of therapy-related acute promyelocytic leukemia (t-APL) with a subclone accompanied by karyotype 46, XX, t(9; 22)(q34;q11), t(15 ;17)(q22;11 to approximately 12) at onset. A 75-year-old woman was diagnosed as having non-Hodgkin lymphoma of the thyroid gland in July 1997. She was treated with a CHOP-like regimen, but complete remission (CR) was not achieved. She then underwent surgical resection of her thyroid gland, and was treated with etoposide (total dose 16775 mg) from February 1998 to May 2000. In June 2000, having developed t-APL, she was referred to our department. The patient attained CR following treatment with chemotherapy containing all-trans retinoic acid. Ten months later she relapsed, but lost the t(9;22), while maintaining the t(15;17).