Spinal epidermoid cyst: illustrative case.

BACKGROUND: Spinal epidermoid cysts are rare, benign lesions accounting for less than 1% of all spinal tumors. They may be congenital or acquired following trauma or spinal procedures. Although slow-growing, their mass effect can cause progressive neurological symptoms. Resection remains the mainstay of treatment, but they may recur when complete removal is limited by adherence to neural structures. OBSERVATIONS: A 71-year-old female with prior lumbar surgery presented with back pain and radiculopathy after multiple falls. MRI revealed a recurrent intradural extramedullary lesion at L1-2. She underwent endoscope-assisted revision laminectomy with gross-total resection. Pathological analysis confirmed an epidermoid cyst. Postoperatively, the patient remained neurologically stable without recurrence at 3 months. LESSONS: Endoscope-assisted microsurgical resection provides excellent visualization for safe, effective removal of spinal epidermoid cysts. Despite favorable outcomes, long-term follow-up is essential due to the risk of recurrence. https://thejns.org/doi/10.3171/CASE25909.