KMT2A and acute myeloid leukemia: Although it is found that there are many risk factors for hyperleukocytosis in AML, even including cytogenetic and molecular biological characteristics, such as M4 and M5, MLL gene abnormalities, and FLT3-ITD mutations (Schoch et al., 2003; Pastore et al., 2015; Shallis et al., 2020).