We have studied a series of 98 n-PTCLs samples (comprising 57 AITL and 41 PTCL-NOS cases) with five TFH antibodies (CD10, BCL-6, PD-1, CXCL13, ICOS), and looked for mutations in five of the genes most frequently mutated in AITL (TET2, DNMT3A, IDH2, RHOA, PLCG1) using the NGS Ion Torrent platform. Here, ICOS is linked to mature T-cell and NK-cell non-Hodgkin lymphoma.