Acute Promyelocytic Leukemia

Acute promyelocytic leukemia (APL) is a specific type of AML characterized by the morphology of blasts, t(15;17) translocation, PML-RAR alpha gene fusion and coagulopathy combining DIC and fibrinolysis. All-trans retinoic acid (ATRA), and arsenic trioxide (ATO), have greatly improved the treatment of APL, yielding 90 to 95% CR rates and 75 to 80% cure rates. The combination of ATRA to conventional anthracycline-based chemotherapy is superiority than chemotherapy alone in newly diagnosed APL while prolonged maintenance treatment with ATRA and low-dose chemotherapy, and possibly very early introduction of anthracycline-chemotherapy during induction treatment, reduce the incidence of relapse. Patients with baseline WBC counts >10 g/L, who remain at higher risk of early death and relapse, benefit from intensive initial supportive care and reinforcement of post-induction treatment. Most of APL patients who relapse after ATRA and chemotherapy can be salvaged by arsenic derivatives followed by allogeneic or autologous stem cell transplantation.