ETV6 and leukemia: Clonal replication results in leukemia if more than 25% of the nucleated cells in the marrow compartment are B-cell lymphoblasts or if there are less than 20% lymphoblasts but the patient presents with any of the following known recurring cytogenic abnormalities: hypodiploidy; hyperdiploidy; translocation t(12;21)(p13;q22) ETV6-RUNX1 (formerly TEL-AML1); t(9;22)(q34;q11.2) BCR-ABL1; t(5;14)(q31;q32) IL3-IGH; t(1;19)(q23;p13.3) TCF3-PBX1; and MLL rearrangements including t(4;11), t(11;19), t(9;11) [19].