WT1 expression as a marker of minimal residual disease predicts outcome in acute myeloid leukemia when measured post-consolidation

WT1 levels may be a useful predictor of leukemia free survival (LFS) following treatment of acute myeloid leukemia (AML). We report a retrospective study in which levels of WT1 expression from patients with de novo AML were measured from bone marrow and peripheral blood at diagnosis, post-induction, post-consolidation and relapse. We demonstrate that higher levels of WT1 in peripheral blood at diagnosis are associated with poorer LFS independent of age and cytogenetic risk-group (n= 85, p= 0.028). When measured at post-consolidation, the presence of detectable WT1 is associated with poorer LFS in univariate analysis of both peripheral blood (p= 0.024) and bone marrow (p= 0.019). In a multivariate analysis including age and cytogenetic risk, the association remained significant for bone marrow (p= 0.016) with a trend observed for peripheral blood (p= 0.06). These findings have formed the basis for ongoing research.