At diagnosis, this patient presented with CN-AML with NPM1 mutation (no DNA sample was available for targeted NGS), while at first relapse the NPM1 mutation was eradicated and, in the meantime, monosomy 7, NRAS, and WT1 mutations emerged, raising the possibility that instead of a clonally related relapse, the patient had developed therapy-related AML. The gene discussed is NPM1; the disease is acute myeloid leukemia.