Minimal residual disease.

The aim of minimal residual disease (MRD) studies in patients with acute leukemia is to measure initial treatment response accurately, provide an assessment of the residual leukemic burden throughout therapy and detect relapse early. Therefore, information resulting from MRD monitoring can substantially improve many facets of clinical management. Methods for MRD detection, namely flow cytometry and PCR, have been applied to study the remission status of thousands of patients with acute lymphoblastic leukemia and acute myeloid leukemia. Collectively, the data indicate that MRD is a powerful prognostic indicator and an indispensable parameter for risk-adapted therapy. The current status of MRD in acute leukemia is briefly reviewed in this paper.