CD40LG and angioimmunoblastic T-cell lymphoma: As the neoplastic TFH cells preserve at least some T‐helper functions, their clonal expansion and particularly their ectopic spatial extension may trigger dysregulated ‘exaggerated’ help to a range of immune responses through both cognate interactions and the release of soluble cytokines and ligands, such as CXCL13, CD40L, ICOS, interleukin (IL)‐6 and IL‐21, contributing to the polymorphous infiltrate commonly seen in tissue biopsies, particularly in patients with AITL associated with clonal haematopoiesis.14, 15, 22, 23