Dysembryogenetic spinal tumours in adults without dysraphism.

The authors report 15 patients with spinal intradural dysembryogenetic tumours with clinical onset in adult age in the absence of clinical and radiological signs of dysraphism. The series includes seven lipomas, four epidermoid cysts, three dermoid cysts and one teratoma. The tumour site was the thoracic region in three cases, the lumbar cord and conus in six, the cauda equina in four and the filum terminale in two. Among 14 patients operated upon, the surgical removal was complete in eight cases, subtotal in two and partial in four. Recurrence was noticed only in one subtotally resected thoracic epidermoid cyst. Magnetic resonance imaging allows a precise diagnosis of these lesions, mainly of small lipomas and dermoids of the conus and filum, where a tethered conus is responsible for clinical symptoms. Dysembryogenetic spinal rumours that become symptomatic in adult age may require surgical treatment. Reduction of the mass and release of any associated tethered neural elements are the goal of surgery for spinal lipomas, whereas epidermoid and dermoid cysts require a more radical treatment. However, even partial resections to avoid neural damage result in a good clinical outcome and very low risk of recurrence.