ALK and angioimmunoblastic T-cell lymphoma: According to the International T-Cell Lymphoma Project [6], the most common subtypes are PTCL-not otherwise specified (PTCL-NOS) (25.9%), angioimmunoblastic T-cell lymphoma (AITL) (18.5%), and anaplastic large cell lymphoma (ALCL) (12.1%), which might be positive or negative for anaplastic lymphoma kinase (ALK).