Consistent with some data reported on NHL patients treated with anti-CD19 CAR-T cells,7,20 the best response to tandem CAR-T cell treatment was independent of the features of the patient’s previous treatment (number of lines of treatment, treatment resistance or relapse), tumour Ki67 expression and gene mutation (Supplementary Fig. S1). Here, MKI67 is linked to non-Hodgkin lymphoma.