2020 Volume 57 Issue 3 Pages 240-250
Acute myeloid leukemia (AML) accounts for approximately 25% of pediatric leukemia cases, with approximately 180 patients newly diagnosed each year in Japan. In general, AML is classified into three groups [acute promyelocytic leukemia (APL), myeloid leukemia associated with Down syndrome (ML-DS), and others] and is treated with different treatment strategies. Retinoic acid with conventional chemotherapy leads to a safe and promising outcome in patients with APL. Recently, arsenic trioxide and gemtuzumab ozogamicin have been expected to reduce late complications and further improve treatment outcomes. Reduced-intensity chemotherapy is effective for patients with ML-DS; however, the prognoses of relapsed and refractory patients are dismal. Optimization of the classification of patients with ML-DS into several groups is desired; thus, the measurement of minimal residual disease by flow cytometry and the detection of GATA1 mutations is expected. For patients with other types of AML, they may be further classified into three groups on the basis of risk stratification according to chromosome and genetic analyses and chemosensitivity to induction therapy. However, the prognosis of patients with a refractory or relapsed disease remains a serious problem that should be solved. A novel therapeutic approach that includes the use of FLT3 inhibitors, which has recently been approved in Japan for adult patients with relapsed and refractory AML bearing FLT3-ITD, will be necessary to improve their prognosis.
