This recurrent abnormality, which is observed in 29-52% of ENKTCL arising in immunocompetent individuals, encompasses loci of the FOXO3 and PRDM1 genes, which have been shown to function as tumor suppressors in ENKTCL and subtypes of PTCL. Here, FOXO3 is linked to mature T-cell and NK-cell non-Hodgkin lymphoma.