WT1 as a universal marker for minimal residual disease detection and quantification in myeloid leukemias and in myelodysplastic syndrome.

Monitoring of acute leukemia patients during and after treatment for the presence of remaining leukemic cells (minimal residual disease, MRD) has been shown to give major insight into the effectiveness of treatment. However, so far the applicability of this strategy has been limited to those leukemia subsets characterized by genetic markers amenable to sensitive detection by PCR. Although PCR for immunoglobulin and T cell receptor gene rearrangement represents the gold standard for MRD detection in most cases of ALL without any fusion gene transcripts as molecular markers available, the situation in AML is more complicated because, at present, more than 50% of them lack any sort of clonality markers suitable for MRD monitoring. Thus, a number of studies have been performed in an attempt to identify cytogenetic and molecular abnormalities associated with leukemic transformation. In this paper we describe the effectiveness of the quantitative assessment of the Wilms tumor gene (WT1) transcript as a molecular marker for the detection of the leukemic clone useful for monitoring the presence of MRD in all the patients affected by acute and chronic leukemias as well as myelodysplastic syndromes. Copyright 2004 S. Karger AG, Basel