WT1 and acute myeloid leukemia: According to this cut-off value, AML cases who received a WT1-positive PBSC graft (with >80 WT1 copies/104 ABL) had a relapse incidence of 87% vs. 31% of patients who received a WT1-negative PBSC graft (p = 0.0001); OS and DFS were 25% and 25% for the WT1-positive group vs. 90% and 75% for the WT1-negative group (p = 0.0001) [50].