PDGFRB and acute lymphoblastic leukemia: Since the <i>GTF2I</i>-<i>PDGFRB</i> could be detected only after molecular studies of the leukemic cells, further investigations of ALL-cases, perhaps especially but not exclusively with a normal karyotype, are needed in order to determine the frequency of <i>GTF2I</i>-<i>PDGFRB</i> in leukemia, and also to find out which clinical impact the fusion may have.