First reported case of intradural extramedullary epithelioid hemangioma of the cauda equina: resection of an extremely rare vascular neoplasm. Illustrative case
TL;DR
This is the first reported intradural EH at any spinal level and recognition of epithelioid endothelial morphology combined with a comprehensive vascular and melanocytic immunohistochemistry panel is essential for diagnosis and separates EH from more common intradural vascular differentials.
Abstract
BACKGROUND Intradural extramedullary (IDEM) tumors of the cauda equina are most often meningiomas, nerve sheath tumors, and myxopapillary ependymomas; purely vascular IDEM lesions are exceptionally rare. Fewer than 30 IDEM hemangiomas have been reported, mostly cavernous or capillary. Epithelioid hemangioma (EH), a benign vascular neoplasm arising in soft tissue and bone, has not previously been reported at the cauda equina. OBSERVATIONS A 63-year-old male with prior cutaneous melanoma presented with 3 months of progressive left L5-distribution radicular pain. MRI showed a 1.0 × 2.0–cm well-circumscribed IDEM mass at L4–5 with left L5–S1 foraminal stenosis. Under intraoperative ultrasound localization and continuous multimodal neurophysiological monitoring, en bloc gross-total resection was achieved through L4–5 laminectomy. Histopathological analysis revealed a well-circumscribed vascular neoplasm with lobular endothelial architecture and no cytological atypia; immunohistochemical analysis (ERG, CD31, and CD34 positivity; HHV8, inhibin, and melanocytic marker negativity) established the diagnosis of EH. At the 7-week follow-up, gross-total resection was confirmed on postoperative MRI. LESSONS To the authors’ knowledge, this is the first reported intradural EH at any spinal level. Recognition of epithelioid endothelial morphology combined with a comprehensive vascular and melanocytic immunohistochemistry panel is essential for diagnosis and separates EH from more common intradural vascular differentials. https://thejns.org/doi/abs/10.3171/CASE26857