BTK and diffuse large B-cell lymphoma: Moreover, in a phase I/II clinical trial assessing the BTK inhibitor ibrutinib as a single treatment in 80 relapsed or refractory human DLBCL patients, 37% of ABC-DLBCL patients responded to the treatment, whereas only 5% of the patients with the germinal center B-cell subtype of DLBCL (GCB-DLBCL) did [7].