Although more than 25 different entities are currently listed in the World Health Organization (WHO) classification (Swerdlow et al., 2016; Swerdlow et al., 2017), the most common nodal PTCL subtypes include anaplastic large-cell lymphoma ALK+ and ALK-, angioimmunoblastic T-cell lymphoma and other T-follicular helper-derived tumors, and peripheral T-cell lymphoma—not otherwise specified (PTCL/NOS). Here, ALK is linked to mature T-cell and NK-cell non-Hodgkin lymphoma.