More recently, we succeeded in identifying a gene signature discriminating between PTCL/NOS and AITL (fig 2).22 In addition, the observed AITL global profile strengthened its derivation from the follicular T helper lymphocyte (FTHL), as originally proposed by Rüdiger et al83 and de Leval et al. 17 Among upregulated genes, were those encoding for CXC13, PD1 and vascular endothelial growth factor (VEGF). Here, PDCD1 is linked to mature T-cell and NK-cell non-Hodgkin lymphoma.