We have demonstrated that 12-0-tetradecanoylphorbol-13-acetate (TPA) combined with vitamin D(3) (VD(3)) and cytosine arabinoside (Ara C) is effective and feasible for chronic myelogenous leukemia (CML) in blastic phase (BP). In the current study, the efficacy of TPA combined with inhibitor imatinib mesylate (imatinib) was investigated in patients with CML in BP that was resistant to standard-dose imatinib (400mg/day). The results suggested that TPA combined with imatinib (400mg/day) might overcome disease-poor response to conventional doses. So this approach deserves further evaluation as frontline therapy for newly diagnosed CML.