Endometrial stromal sarcoma metastasis to the lumbar spine and sphenoid bone

Endometrial stromal sarcoma (ESS) is typically associated with metastasis to the abdomen, pelvis, and lung. We found three case reports of ESS metastasis to the bone (two to the thoracic spine, and one to the parietal bone). Our objective is to review the literature on ESS spinal and intracranial metastases and, report the first case of ESS metastatic to the lumbar paraspinal region and sphenoid bone. A 53-year-old female with ESS status-post radiation, chemotherapy, and pelvic exenteration surgery presented with right hip weakness, back pain, and radicular leg pain that were explained by chemotherapy-induced neuropathy, radiation-induced lumbosacral plexopathy, and femoral nerve and obturator nerve injury during pelvic exenteration surgery. During routine positron emission tomography, we found metastasis to the L3 lumbar spinal region. L3 laminectomy and subtotal resection of the mass was performed with tumor residual in the neuroforamina and pedicles. One month later, magnetic resonance imaging (MRI) performed for persistent headaches revealed a large lesion in the sphenoid bone that was biopsied transsphenoidally with the same diagnosis, but no further surgery was performed. She is intolerant of chemotherapy and currently undergoing whole brain radiation. Delay in the diagnosis and management of lumbar paraspinal and sphenoid bone metastasis of ESS likely occurred because of the uniqueness of the location and aggressiveness of ESS metastasis. Health care providers should be aware of potentially aggressive metastasis of ESS to bone, in particular the unusual locations of the lumbar paraspinal region and sphenoid bone.