KMT2A and acute lymphoblastic leukemia: Subsequently, based on the obtained data, we have assigned B-ALL patients to four categories: (1) “bad” primary aberrations, which grouped patients with all markers of poor prognosis (i.e., MLL rearrangements, BCR::ABL-like aberrations, complex, hyperdiploid, and hypodiploid karyotype), (2) “good” ones (E2A::PBXpos), as well as “intermediate” ones (IM), which included 2 subgroups: (3) BCR::ABL1pos and (4) NEG ALL (Figure 2C,D; Table 3A).