A recent study evaluated the impact of high-risk cytogenetic abnormalities on the outcomes of children and young adults with CD19-positive B-cell precursor acute lymphoblastic leukemia (B-ALL) or lymphoblastic lymphoma treated with CD19-directed chimeric antigen receptor (CAR) T-cell therapy (NCT01626495, NCT02435849, NCT02374333, NCT02228096, and NCT02906371) (115). This evidence concerns the gene CD19 and lymphoblastic lymphoma.