ABC DLBCL is characterized by B-cell-receptor dependence, constitutive nuclear factor-κB activation, and interferon regulatory factor4 (IRF4) /MUM1 multiple myeloma oncogene1 (MUM1) expression, while GCB DLBCL is characterized by CD10 expression and BCL2 rearrangements [8, 34, 35]. The gene discussed is IRF4; the disease is aneurysmal bone cyst.