ABSTRACT
This chapter addresses the unique biology of Acute promyelocytic leukemia (APL), the role of all-trans retinoic acid (ATRA) in differentiation therapy and arsenic trioxide (ATO) in inducing apoptosis. Both agents contribute to the remarkable cure rates in APL. Until the 1990s, combination chemotherapy with an anthracycline and cytosine arabinoside was the standard treatment for APL. Although ATRA is an extremely effective drug in APL, this agent has the limitation of being available only in an oral formulation. ATO has a dual mechanism of action in APL patients ATRA is the treatment of choice for all patients with newly diagnosed APL. Synergy between ATRA and ATO may permit a reduction or possibly elimination of chemotherapy in most patients. This approach could be used in conjunction with gemtuzumab ozogamicin for induction and potentially offer patients with a curative approach without the use of standard intensive chemotherapy.
