Wilms' tumor gene 1 expression: an independent acute leukemia prognostic indicator following allogeneic hematopoietic SCT

To evaluate the prognostic significance of Wilms' tumor gene 1 (WT1) expression for monitoring minimal residual disease and predicting relapse in patients with acute leukemia (AL) following allogeneic hematopoietic SCT (allo-HSCT), the WT1 expression levels of 138 AL patients were measured using real-time quantitative reverse transcription PCR at designed time points after allo-HSCT. All patients were divided into four groups based on the HSCT outcomes and intervention application. A low level of WT1 expression following HSCT indicated a low risk of relapse, whereas WT1 expression >1.05% was indicative of a higher probability of relapse. Only the advanced stage of disease (hazard ratio (HR) = 2.73; 95% confidence interval (CI) = 1.337-5.573, P = 0.006) and a WT1 expression >= 0.60% (HR = 4.774; 95% CI = 2.410-9.459, P = 0.000) were associated with lower disease-free survival. Relapse (HR = 0.119; 95% CI = 0.056-0.250, P = 0.000) and a WT1 expression >= 0.60% (HR = 2.771; 95% CI = 1.316-5.834, P = 0.007) were associated with lower OS. In conclusion, the WT1 expression level is an independent prognostic factor that can predict clinical outcomes for AL patients after HSCT and provide a guide for suitable interventions. Bone Marrow Transplantation (2012) 47, 499-507; doi:10.1038/bmt.2011.121; published online 6 June 2011