KMT2A and acute lymphoblastic leukemia: The information synthesized in this review is derived from a search of published literature in databases such as PubMed/MEDLINE and Web of Science using the search terms: ‘KMT2A-AFF3’, ‘t(2;11)(q11.2;q23)’, ‘MLL-LAF4’, ‘MLL-AFF3’, and ‘childhood KMT2A-rearranged ALL’.