The association of level of reduction of Wilms' tumor gene 1 mRNA transcript in bone marrow and outcome in acute myeloid leukemia patients.

We focused on the level of reduction of Wilms' tumor gene 1 (WT1) mRNA in bone marrow as minimal residual disease during chemotherapies in adult acute myeloid leukemia (AML) patients. Forty-eight patients were enrolled in this study. Log levels of reduction of WT1 mRNA transcript after induction therapy compared with those at diagnosis were associated with disease-free survival (DFS) (P=0.0066) and overall survival (OS) (P=0.0074) in patients who achieved complete remission. Also log levels of reduction of WT1 mRNA transcript after final consolidation therapy compared with those at diagnosis were associated with DFS (P=0.015) and OS (P=0.012). By multivariate analysis, log levels of reduction of WT1 mRNA transcript after induction therapy and after final consolidation therapy compared with those at diagnosis were extracted as risk factors for outcome. Our results suggest that early and deep reduction of tumor burden may be important for the outcome of AML patients. In addition, it may be useful for the decision to proceed with allogeneic SCT as post-remission therapy.