Acute myeloid leukemia concurrent with spinal epidural extramedullary myeloid sarcoma accompanied by a high CD25 expression and the FLT3-ITD mutation.

Abstract Myeloid sarcoma (MS) is an extramedullary myeloid tumor that sometimes presents with antedating systemic leukemia, leading physicians to the misdiagnosis of lymphoma. CD25 is expressed in 13% of patients with acute myeloid leukemia (AML), and its expression is associated with FLT3-ITD mutations, an elevated serum soluble interleukin 2 receptor (sIL-2R) level and a lower survival rate. However, there are no reports concerning the relationship between MS and the CD25 expression. We herein report a case of AML accompanied by thoracic epidural MS with a high CD25 expression, the FLT3-ITD mutation and an extremely elevated serum sIL-2R level in a 59-year-old man who presented with paraplegia.