NPM1 and acute myeloid leukemia: Furthermore, according to Kronke et al., NPM1-mutated transcript levels were an independent prognostic factor also when analyzed after completion of consolidation therapy (4-year OS 80% and 44% for MRD-negative and MRD-positive patients, respectively) and during follow-up, when serial MRD monitoring allowed early prediction of AML relapse in patients exceeding an arbitrary cut-off value of greater than 2% NPM1-mutated/ABL1 [40].