MYC rearranged lymphoblasts show FAB L2 or L3 cytomorphology without surface expression of immunoglobulin light chains and can be confused with mature B-cell leukemia/lymphoma; nevertheless, the absence of somatic hypermutation (VDJ rearrangement of the IGVH genes) in pediatric B-ALL is the principal difference [27,30]. The gene discussed is MYC; the disease is precursor B-cell acute lymphoblastic leukemia.