Therefore, although the increase in CAR T‐cell uptake in CD19‐positive tumours is very limited compared with CD19‐negative tumours, CAR T cells can survive longer in CD19‐positive tumours due to their ‘live’ nature, resulting in a dramatic difference in efficacy between the two groups, which demonstrates the magic of CAR T‐cell immunotherapy. The gene discussed is CD19; the disease is neoplasm.