This disease originates from the tumoral transformation of B cells, with DLBCL represented by two main subtypes: i) the germinal B-cell like (GCB), expressing CD10 and BCL2 rearrangements, and ii) the activated B-cell like (ABC), the most aggressive form that is derived from post-germinal center B cells with B-cell Receptor dependence, constitutive NF-kB activation, and IRF4/MUM1 expression (71). The gene discussed is IRF4; the disease is diffuse large B-cell lymphoma.