TCF3 and precursor B-cell acute lymphoblastic leukemia: Among the genetic alterations found in B-ALL, TCF3–PBX1 t(1;19), ETV6–RUNX1 t(12;21), and hyperdiploidy are associated with a favorable outcome while MLL rearrangements, TCF3–HLF t(1;19) and rearrangements of CRLF2, JAK2A, or BL-class tyrosine kinase genes are of poor prognosis [111,112].