Adult Intramedullary Mature Teratoma of the Spinal Cord: An Unusual Case with a Review of the Literature

Abstract

Intraspinal teratoma is a rare subtype of spinal cord tumors, accounting for only 0.2% to 0.5% of cases. These tumors consist of a mixture of two or more germ cell layers, including the ectoderm, endoderm, and mesoderm. They often contain epithelial tissues, fatty tissues, and follicles derived from these three layers, which can be visualized on magnetic resonance imaging (MRI) in most cases. However, in our patient, a 35-year-old woman with an intradural oval intramedullary teratoma at the L4 level, the tumor exhibited features similar to those of a schwannoma. On MRI, the tumor appeared as a 2-cm mass attached to the end of the spinal cord, with intermediate signal intensity on T2-weighted images and iso-intensity without enhancement on T1-weighted images. L4 laminoplasty with tumor removal was performed under intraoperative monitoring. The tumor was found to be firm with a cyst containing mucoid and fatty tissue posteriorly. Near-total resection was achieved, although the tumor margin was indistinct. A literature review revealed spinal cord tethering and the presence of fatty tissue without MRI enhancement as characteristic findings of teratomas and dermoid cysts. Key words: Dermoid cysts; Spine; Spinal cord neoplasms; Teratoma