Nondysraphic Intramedullary Spinal Cord Lipomas in the Adult Population

OBJECTIVE: Intramedullary spinal cord lipomas without spinal dysraphism are rare. Although they are benign tumors, they can cause significant neurological deficits. Their tight adherence to the spinal cord presents a challenge for resection. Therefore, we review our institutional experience treating adult patients with intramedullary lipomas in the absence of dysraphism and report long-term outcomes after resection. METHODS: All adult patients undergoing resection of intramedullary spinal cord lipomas at a comprehensive cancer center between June 2011 and June 2023 were retrospectively identified. Patients with spinal dysraphism or extramedullary lipomas were excluded. Patients were included if they had microscopic surgical debulking with tissue sampling confirming the diagnosis. RESULTS: Six patients were identified with a mean age of 35.0 +/- 11.5 years, and 67% were female. Four cases localized to the thoracic spine. Symptoms included pain, numbness, and lower extremity motor weakness; only one patient reported bowel and bladder dysfunction. All patients experienced transient neurological decline in the immediate postoperative period. Five recovered to independent ambulation at long-term follow-up, including one recovering to full strength. One patient required a repeat resection after four years due to tumor progression and functional decline. Tumor progression was not recorded in the other patients. CONCLUSIONS: Subtotal resection is a safe and effective treatment. Detethering of the spinal cord, resection of exophytic components, and tumor debulking can improve symptoms and prevent further deterioration in most cases. The resection can be assisted using a laser to vaporize the fatty tissue of the lipoma without physical manipulation of the spinal cord.