Myeloid sarcoma presenting as a recurrent, multifocal nerve root entrapment syndrome

Background: Myeloid sarcoma is an extramedullary manifestation of haematologic malignancy, most commonly acute myeloid leukemia (AML), which can cause neurological symptoms. Case description: A 45-year-old male with a history of AML presented with a lumbosacral nerve root entrapment syndrome followed by cauda equina compression, but without systemic signs of AML recurrence. MRI showed a mass compressing the spinal cord at level L5-S2. After surgically removing the tumour pathologic examination yielded a myeloid sarcoma. Combined chemotherapy and radiation therapy followed. Five months later the patient developed a thoracal (Th10-Th11) radiculopathy due to a relapse of the myeloid sarcoma, followed by C8-Th1-radiculopathy caused by leptomeningeal spread. Conclusion: This case forms the first description of recurrent, multifocal and progressive radiculopathy due to myeloid sarcoma. This diagnosis should be considered in patients with radiculopathy with previous haematological malignancy and/or signs or symptoms of such disease; the absence of systemic disease activity does not rule out myeloid sarcoma.