Myeloid/lymphoid neoplasms with eosinophilia and specific gene rearrangements: a genetic approach

Eosinophils are granular leukocytes derived from a pluripotent stem cell in the bone marrow. An increase in the number of eosinophils in the blood and/or tissues requires a multifaceted clinical approach. It is important to determine the cause of the increase in order to make a correct diagnosis. Myeloid/lymphoid neoplasms with eosinophilia and specific gene fusions involve abnormal tyrosine kinase or cytokine receptor activity. Due to the similarity and heterogeneity of clinical findings, there may be diagnostic confusion in this group of diseases. Confirmation of the diagnosis is possible with genetic testing. This article briefly summarises the genetic approach to myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions.