As per the WHO classification, chronic eosinophilic leukemia is also called myeloid/lymphoid neoplasm with eosinophilia and abnormalities of PDGFRA, PDGFRB, FGFR1, or PCM1-JAK2 (1). This evidence concerns the gene PDGFRA and Chronic Eosinophilic Leukemia, Not Otherwise Specified.