(A) OS in AML patients with and without karyotypic change between diagnosis and relapse. The 2 groups (P=0.004) showed significant differences in OS. (B) EFS in AML patients with and without karyotypic change between diagnosis and relapse. Karyotypic change was significantly associated with EFS after relapse (P=0.010). ^a)Cases with changed karyotypes between diagnosis and relapse; ^b)Cases without changed karyotypes between diagnosis and relapse. Abbreviations: AML, Acute myeloid leukemia; OS, overall survival; EFS, event-free survival.