Low back pain and lumbar radiculopathy as harbingers of acute myeloid leukemia recurrence in a patient with myeloid sarcoma.

Myeloid sarcoma (MS) is an extra-osseous, solid collection of myeloblasts. It is associated with myeloid leukemias, and rarely affects the spine. The most common clinical presentation of MS in spine patients is some form of pain related to compression of neural elements. Given that MS is rare, and its imaging characteristics are similar to other more common diagnoses, it is frequently missed on initial presentation. We present a 28-year-old female, in her fifth year of remission from AML, with low back pain and right lumbar radiculopathy. Initially, the leading diagnosis was schwannoma in preference to neurofibroma; however, intra-operative pathology and subsequent bone marrow biopsy revealed the tumor to be MS. This report highlights the difficulties of diagnosis of MS in patients in remission from acute myeloid leukemia. Thus, in patients with a history of leukemia, MS should be considered in the differential diagnosis of any epidural or nerve root tumor. Timely diagnosis and treatment are key to optimal outcomes.