CARS1 and neoplasm: Clinically, three main avenues have been investigated: (1) tumour infiltrating lymphocytes (TIL) isolated from the patient ́s tumour; (2) peripheral blood T cells transduced with T cell receptors (TCR) specific for cancer-associated antigens; and (3) peripheral blood T cells transduced with synthetic receptors, the so called chimeric antigen receptors (CARs).1,2 All three strategies have and are being investigated in clinical trials with varying success rates.3 The most advanced clinical strategies are CAR T cells specific for the B-cell differentiation antigen CD19.