TCF3 and B-cell acute lymphoblastic leukemia: Translocation t(1;19)(q23;p13.3), generating TCF3::PBX1 fusion, found in pre-B cell acute lymphoblastic leukemia, results in a chimeric protein that is directly associated with malignant transformation of hematopoietic cells and is observed in both adults and children with B-ALL at an overall frequency of 5–6% [82,130].