Chimeric antigen receptor (CAR) immunotherapy is a revolutionary treatment in hematological malignancies, especially CD19 CARs in B-cell malignancies.73 The success of CD19 CARs in treating CNS diffuse large-B-cell lymphoma demonstrated CAR T cells could go through the blood–brain barrier.74 CD5 is one of the surface antigens expressed on T-cell malignancies but not hematopoietic stem cells.75 A relapsed T-LBL patient with CNS involvement improved symptoms and remitted disease after treatment with CD5-IL15/IL15sushi CAR-T-cell immunotherapy. This evidence concerns the gene CD19 and diffuse large B-cell lymphoma.