The most common subtypes include PTCL-not otherwise specified (PTCL-NOS), extra-nodal natural killer (NK)/T cell lymphoma, nasal type (ENKTL), angioimmunoblastic T-cell lymphoma (AITL), anaplastic large-cell lymphoma (ALCL), include ALCL anaplastic lymphoma kinase positive(ALCL, ALK +), and ALCL anaplastic lymphoma kinase negative (ALCL, ALK-). Here, ALK is linked to anaplastic large cell lymphoma.