Minimal residual disease in childhood acute lymphoblastic leukemia: current status and challenges.

The pace of disappearance of leukemic blasts in response to therapy has long been recognized as the most important prognostic factor in childhood acute lymphoblastic leukemia (ALL). Recent technological advancements enable detection of submicroscopic leukemic cells. The extent of reduction in the level of minimal residual disease (MRD) during the first phase of therapy can be exploited for improved risk classification of children with ALL. Current prospective studies test the hypothesis that tailoring treatment to the level of MRD will improve patients' outcome. Copyright 2004 S. Karger AG, Basel