Chimeric antigen receptor (CAR)-modified T cells already demonstrated outstanding results for the treatment of B cell neoplasms such as CD19+ B cell acute lymphoblastic leukemia as well as B cell maturation antigen (BCMA)+ multiple myeloma which led to the approval of multiple drugs by the U.S. Food & Drug Administration (FDA) as well as the European Medicines Agency (EMA) [1–4]. This evidence concerns the gene TNFRSF17 and B-cell acute lymphoblastic leukemia.