NOTCH1 and acute lymphoblastic leukemia: As the presence of mutations in TP5342, 43 or RAS17 at the time of diagnosis of T‐ALL have been reported to be correlated with an unfavorable outcome, and seven of 14 NOTCH1‐mutated patients also had mutations of K/NRAS or TP53, we speculated that this unexpected negative result may be due to presence of the co‐mutation.