Kaplan-Meier estimates of OS according to NOTCH1 mutation status. Overall survival according to NOTCH1 mutation status in the CLL training series (n = 309; A) and in the CLL validation series (n = 230; B). NOTCH1 germ line cases (NOTCH1 GL) are represented by the blue line. NOTCH1 mutated cases (NOTCH1 M) are represented by the red line.