Large thoracic extradural schwannoma atypically invading T2 vertebra

Abstract

A 53-year-old woman presented with a complaint of back pain. Her medical history and physical examination were unremarkable. Magnetic resonance imaging of the thoracic spine showed a large extradural mass on the right side at the T2– T3 levels (Fig. 1). The lesion widened the right neural foramen and had a large extraspinal component with extension into the posterior mediastinum. The lesion invaded the posterior and right posterolateral parts of the T2 vertebral body (Fig. 2). It was heterogeneously hypointense to muscles on T1weighted, and hyperintense on T2-weighted images. Postcontrast images showed intense enhancement of the lesion. The tumor was resected, and T2 corpectomy was also performed. Histopathologic examination revealed the diagnosis of schwannoma without malignant transformation. Schwannoma is the most common spinal nerve sheath tumor, which is followed by neurofibroma and ganglioneuroma. Invasion and osteolytic expansion of the vertebral body by schwannoma is extremely rare. Schwannoma should be included in the differential diagnosis of large extradural lesion causing invasion and destruction of the spine, especially if it shows typical imaging findings such as neural foraminal widening and adjacent bony remodeling [1].