Congenital lumbosacral meningocele with malignant transformation to epithelioid angiosarcoma: A case report of complex spinal anomalies.

Congenital neural tube defects rarely manifest in adulthood, and malignant transformation of meningocele is exceptionally rare. This report describes a rare case of a 56-year-old male with a congenital lumbosacral meningocele that underwent malignant transformation to epithelioid angiosarcoma, coexisting with multiple spinal anomalies, including tethered cord and diastematomyelia. Following admission and diagnostic workup, the patient underwent surgical intervention. Tumor recurrence occurred 3 months after surgery, and received combined radiotherapy and targeted therapy. Follow-up magnetic resonance imaging demonstrated regression of the recurrent tumor; however, the patient died 1 year after surgery. This case highlights that chronically untreated meningoceles may undergo malignant transformation due to persistent irritation, necessitating vigilance for lesion changes and early biopsy.