Teaching NeuroImages: sacral spine chloroma.

A 23-year-old man with recurrent acute myeloid leukemia (AML) underwent successful reinduction and was judged posttherapy to be in complete remission. Soon thereafter, he complained of pain in his left buttock radiating into his left posterior thigh. Neurologic examination was unremarkable. Radiographic evaluation demonstrated a left S2 lesion suggestive of a nerve sheath tumor (figure 1). An open biopsy was performed that revealed a chloroma pathologically (figure 2), sometimes referred to as a myeloid sarcoma.(1,2) Most chloromas are found in patients with recurrent AML and are overwhelmingly intracranial.(1) Infrequently, chloromas are paraspinal, and in this location present with epidural spinal cord compression.(2) Intraspinal invasion by a chloroma is rare. Systemic evaluation confirmed recurrent AML, for which he was successfully treated with reinduction and whole-body irradiation followed by an allogeneic transplant. He is currently disease-free and neurologically asymptomatic 1 year posttransplant.