For example, PTCL-NOS and angioimmunoblastic T-cell lymphoma (AITL) bear some similarities in terms of disease presentation, but PTCL-NOS is distinct from AITL in that AITL cells have solely a follicular T-helper phenotype (PD-1+, CXCL13+) and PTCL-NOS can include T-cells from differing subtypes (7). Here, CXCL13 is linked to mature T-cell and NK-cell non-Hodgkin lymphoma.