PDGFRB and acute myeloid leukemia: AML relapsed 1 year after HSCT, when bone marrow cells were negative for both PDGFRB and RUNX1 c.777dupT, p.Asn260*, but still positive for ASXL1 and for 1 out of the 3 RUNX1 variants identified at diagnosis (c.497G > A, p.Arg166Gln) (Table 3).