Acute Myeloid Leukemia Concurrent with Spinal Epidural Extramedullary Myeloid Sarcoma Accompanied by a High CD25 Expression and the <i>FLT3-ITD</i> 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.

Article Commentary: “Spinal Myeloid Sarcoma ‘Chloroma’ Presenting as Cervical Radiculopathy: Case Report”

“…An argument may be made to perform an instrumented arthrodesis given the fact that the lesion and laminectomy spanned the cervicothoracic junction and that there was no known primary at the time, making it difficult to prognosticate the overall expected length of survival, which others have shown can influence the aggressiveness of surgical management. 1 Though this is not an unreported presentation, it is a rare pathology 2,3 ; the previously published literature does support the same treatment paradigm that was undertaken for this patient. Surgical decompression with adjuvant chemoradiation has been the standard used by other practitioners.…”

Rare Intramedullary Myeloid Sarcoma Mistaken as Acute Transverse Myelitis

“…On MRI examination, spinal myeloid sarcoma yields a similar signal intensity to muscle on T1-weighted images (WIs) and intermediate signal intensity on T2-WIs with subtle to intermediate enhancement with Gadolinium 1,4,14) . Immunohistochemistry is the most accurate method for establishing the diagnosis of myeloid sarcoma, and a series of markers can be used for diagnosis confirmation and further lineage characterization 6,9,15,16) . Myeloid sarcoma can rarely occur in patients without any evidence of leukemia and may precede the development of systemic disease 5,9) .…”

“…Myeloid sarcoma can rarely occur in patients without any evidence of leukemia and may precede the development of systemic disease 5,9) . If the patient has established leukemia, the diagnosis of myeloid sarcoma is relatively easy and it is suggested to always be included in the differential diagnosis for patients with leukemia with a soft tissue mass 6,13) . The diagnosis of myeloid sarcoma could be difficult if there is no clinical history of leukemia and every effort should be made to obtain a pathologic diagnosis 4,7,9) .…”

“…The treatment strategy for myeloid sarcoma largely depends on systemic manifestation of leukemic cells and whether it is initial diagnosis or relapse 6,[15][16][17] . The optimal timing and treatment of isolated myeloid sarcoma is still controversial, however, delayed or inadequate systemic treatment will almost always progress to systemic infiltrations 6,8,10,14) . For the patient with myeloid sarcoma who presents with concurrent marrow involvement, systemic treatment is always suggested 5,9,16) .…”

“…Common sites of occurrence are skin, soft tissue, bone, periosteum and lymph nodes, with rare involvement of central nervous system 1,12) . In spinal involvement, myeloid sarcoma usually occurs as an epidural mass with signs of cord compression 6,7,16) . However, a few cases of rare intramedullary involvement have been reported worldwidely 2,9,15) .…”