Nodal PTCLs include ALK-positive (ALK+) and ALK-negative (ALK−) anaplastic large cell lymphoma (ALCL); nodal T-cell lymphoma with T follicular helper (TFH) cell origin; and PTCL, not otherwise specified (PTCL-NOS). This evidence concerns the gene ALK and mature T-cell and NK-cell non-Hodgkin lymphoma.