Leukemias harboring FGFR1 fusions have historically been referred to as 8p11.2 myeloproliferative syndrome (EMS) or stem cell leukemia/lymphoma (SCLL).2,3 The latest World Health Organization (WHO) classification now refers to these diseases as Myeloid/lymphoid neoplasms with FGFR1 rearrangements (MLN-FGFR11). The gene discussed is FGFR1; the disease is eosinophilia-myalgia syndrome.