ALK and anaplastic large cell lymphoma: There are various subtypes of PTCL: anaplastic large cell lymphoma (ALCL) (either with or without anaplastic lymphoma kinase rearrangements), angioimmunoblastic T-cell lymphoma (AITL), PTCL not otherwise specified (PTCL-NOS), and cutaneous T-cell lymphoma (CTCL) [2].