Next‐generation sequencing (NGS) of the ctDNA indicated the presence of T‐ALL gene variants (ARID1A D1462E, FGFR1 R507C, NOTCH1 L1678P, and PTEN L25S), indicative of residual disease before allo‐HSCT. This evidence concerns the gene NOTCH1 and acute lymphoblastic leukemia.