Myeloid and lymphoid neoplasms with eosinophilia and abnormalities of PDGFRA, PDGFRB or FGFR1

A group of rare myeloid and lymphoid neoplasms characterised by rearrangement of the PDGFRA, PDGFRB, or FGFR1 genes, resulting in the formation of fusion transcripts and aberrant tyrosine kinase activity. Eosinophilia is a characteristic finding but it is not always present.