Childhood leukemias--current status and future perspective.

Current chemotherapy will cure at least 65% of children with acute lymphoblastic leukemia (ALL). The major challenge in ALL is to develop effective risk-directed therapy. This approach seeks to improve outcome, through more intensive therapy, for children at high risk of relapse, while reducing the side effects and long-term complications of treatment for those with a high likelihood of cure. The prognosis remains poor for most children with acute myeloid leukemia (AML). Despite the use of intensive chemotherapy and bone marrow transplantation, only 30% to 40% of these patients are long-term survivors. However, research has identified subgroups of patients who will respond well to therapy that is targeted to their specific biologic subtype of AML. Allogeneic bone marrow transplantation remains the only curative treatment for patients with chronic myeloid leukemia. Current efforts focus on improving risk-directed and subtype-specific treatment for the childhood leukemias. Ultimately, it may be possible to target treatments to the specific genetic lesions of leukemic cells.