Advances in the understanding and management of acute promyelocytic leukemia.

Considerable progress has been made over the past decade in the understanding and management of acute promyelocytic leukemia (APL). At the laboratory level, molecular mechanisms underlying the arrest of differentiation that typically features in this malignancy, have been clarified and currently provide important models for addressing future investigation aimed at releasing the maturation block in other malignancies. In the clinic, advances in the management of APL have converted this rapidly fatal disease into the most frequently curable leukemia in adults. Use of retinoids in combinatorial protocols with anthracycline-based chemotherapy for front line treatment currently results in long-term survival and potential cure in at least 60% of newly diagnosed patients. Even after relapse, the disease is still curable in a high percentage of cases by various approaches including combinations of chemotherapy, retinoids, arsenic trioxide, stem cell transplantation and antibody-targeted chemotherapy. Genetic testing for identification of the disease-specific gene rearrangement and monitoring of residual disease have proved critical in establishing correct diagnosis and better evaluate the response to therapy at the molecular level. Current 'hot' issues for clinical investigation include: (i) better understanding and management of the severe coagulopathy present at diagnosis in most patients; (ii) the definition of risk categories to improve identification of patients at highest risk of relapse and (iii) the translation of successful differentiation therapy to other leukemia subsets.