Similar to that observed in B-ALL, a biopsy of renal lesion from a patient with persistent renal involvement by PMLBCL 2 months after anti-CD19 CAR-T cell infusion indicated that activated anti-CD19 CAR-T cells could infiltrate the tumor; however, the PMLBCL clone is absent on surface CD19 but shows positive cytoplasmic expression [29]. This evidence concerns the gene CD19 and acute lymphoblastic leukemia.