[Myeloid/lymphoid neoplasms with eosinophilia and FGFR1 rearrangement: 5 cases report and literatures review].

Objective: To investigate the clinic-pathological features, diagnosis and treatment of 8p11 myeloproliferative syndrome (EMS) . Methods: Five patients diagnosed as EMS from Jan 2014 to May 2018 at Blood Disease Hospital, Chinese Academy of Medical Sciences were enrolled. The clinical manifestations, laboratory characteristics, treatment and outcome of these patients were summarized. Results: The peripheral blood leukocyte count of 5 patients with EMS increased significantly, accompanied with an elevated absolute eosinophils value (the average as 18.89×10(9)/L) . The hypercellularity of myeloid cells was common in bone marrow, always with the elevated proportion of eosinophils (the average as 17.24%) , but less than 5% of blast cells. The chromosome karyotype of the 5 cases differed from each other, but presenting with the same rearrangement of FGFR1 gene by fluorescence in situ hybridization technology. The average interval between onset and diagnosis was 4.8 months with a median survival of only 14 months. Conclusion: EMS was a rare hematologic malignancy with poor prognosis and short survival. It was commonly to be misdiagnosed. Analysis of cytogenetics and molecular biology were helpful for early diagnosis.