Bone marrow WT1 levels in patients with myeloid neoplasms treated with 5-azacytidine: Identification of responding patients.

Introduction: Increased levels of Wilms' tumor (WT1) mRNA have been used to establish risk categories in patients with acute myeloid leukemia (AML). Raised values of WT1 have been associated with progression in myelodysplastic syndrome (MDS).

Methods: We retrospectively analyzed the available bone marrow (BM) samples from 115 patients with myeloid neoplasms obtained before and during treatment with 5-azacytidine. A threshold of 100 copies in BM was used to define risk groups: group 1: patients with WT1 levels always below < 100 copies; group 2: cases with initial WT1 levels greater than 100 copies but with a conversion to sustained levels below 100; and group 3: cases with follow-up WT1 levels greater than 100.

Results: Twenty patients were included in group 1, 17 in group 2, and 78 in group 3. Survival analysis showed statistically significant differences in terms of OS between groups (p: 0.016). Patients in group 2 showed the best 5-year overall survival (OS). In multivariate analysis, only the cytogenetic risk category and receiving an allogeneic hematopoietic stem cell transplantation (HCT) independently predicted the survival.

Conclusions: Further studies are needed to assess whether BM WT1 levels could be useful to predict the survival of patients with myeloid neoplasms treated with 5-azacytidine.