ALK and mature T-cell and NK-cell non-Hodgkin lymphoma: Interestingly, the miRNA signature of ALK-ALCL was found to have a different profile compared with peripheral T cell lymphoma (PTCL), not otherwise specified (NOS), and to partially overlap with the miRNA expression prolife of ALK+ ALCL, suggesting that the pathogenesis of ALK- ALCL is closer to ALK+ ALCL than to PTCL, NOS.