FLT3 and acute promyelocytic leukemia: Secondly, we examined the relationship between the percentage of APL stem-like cells and recurrent mutations in APL patients, including three common isoforms of PML/RARα (L-type, S-type, and V-type)54, FLT3 mutations (ITD and TKD), and mutations involving WT1, NRAS, and ARID1A.