Therapy-related acute myeloid leukemia (t-AML) with poor-risk cytogenetics in two patients with persistent molecular complete remission of acute promyelocytic leukemia

Therapy-related acute myeloid leukemia (t-AML) is a clinical syndrome occurring as a complication after cytotoxic and/or radiation therapy. The incidence of t-AML after acute promyelocytic leukemia (APL), all-transretinoic acid (ATRA), and anthracycline-based therapy is rather low. However, because of the high remission rates and long-term overall survival achieved with current APL treatments, late complications related to antileukemic therapy should be taken into account, giving priority to efficacy agents with the lowest potential of leukemogenesis, despite individual genetic susceptibilities that are not well known. Here, we report two cases of t-AML observed in two young women who achieved a rapid, complete molecular remission (CMR) of APL and who were still in CMR when t-AML was diagnosed. These t-AMLs shared some clinical and biological features such as poor-risk cytogenetics and a rapidly progressing, unfavorable outcome. Retrospective RT-PCR WT1 expression from the onset of APL to t-AML diagnosis did not prove to be a good marker for t-AML development.