The International T-cell Lymphoma Project examined a cohort of 1,314 cases of PTCL and NKTCL and while cases of ALK-positive anaplastic large cell lymphoma (ALCL) had a 70% 5-year overall survival (OS), the remaining subtypes had worse outcomes, with 5-year OS for PTCL-NOS, angioimmunoblastic T-cell lymphoma (AITL), and all NKTCLs of 32% and a more dismal 14% for ATLL. This evidence concerns the gene ALK and mature T-cell and NK-cell non-Hodgkin lymphoma.