In DLBCL, ibrutinib seems to be more effective in patients with an activated B cell-like DLBCL (ABC-DLBCL) subtype rather than in patients with germinal center B cell-like DLBCL (GC-DLBCL) due to constitutively active BCR signaling in ABC-DLBCL. The gene discussed is BCR; the disease is diffuse large B-cell lymphoma.