Lastly, our interesting case of an AITL patient with CH and subsequent development of DLBCL and the sharing of the same TET2 mutation among all three lesions suggest that a subset of DLBCL, possibly the molecular subtype characterized by mutated TET2 (Lacy et al., 2020), may originate from mutated HSC. The gene discussed is TET2; the disease is diffuse large B-cell lymphoma.