PDGFRB and juvenile myelomonocytic leukemia: Fusions involving the tyrosine kinase genes PDGFRB (SPECC1-PDGFRB and NDEL1-PDGFRB) and FLT3 (CCDC88C-FLT3) were also identified in case reports of JMML-diagnosed patients lacking mutations in the classical JMML drivers [65,66,67].