Giant cauda equina schwannoma


Correspondence: Associate Professor Hiroshi Morita, Department of Medicine (Neurology & Rheumatology), Shinshu University School of Medicine, Asahi 3-1-1, Matsumoto 3908621, Japan. Email:

Schwannoma is a benign tumor that often grows from the spinal root.[1-3] A 42-year-old woman first experienced lumbar pain and left-side ischiadic neuralgia at the age of 40 years. Her symptoms progressed gradually; she developed dysesthesia of the left leg and urinary incontinence 6 months before admission. Thereafter, she had gait disturbance, lumbago and pain in both legs. On admission, she had flaccid paraplegia and sensory loss below Th10. Magnetic resonance imaging showed a large tumor occupying the whole lumbar and upper sacral canal associated with thoracolumbar cord syrinx (Fig. 1a,b). The tumor was lobularly enhanced (Fig. 1c,d). A restricted biopsy of the tumor led to the diagnosis of schwannoma (Fig. 1e,f). Because schwannoma grows along with the nerve root from the intradural space to outside of the spinal canal, it sometimes presents as a dumbbell-like appearance. The tumor also grows longitudinally within the dural space and invades into the vertebral bone.[1] These images clearly show a rarely observed, typical invasive pattern of schwannoma.

Figure 1.

(a–d) Magnetic resonance (MR) images of (a) T1, (b) T2 and (c,d) enhanced T1 images. The tumor was lobularly enhanced at the vertebral level of L1–4, and mainly located in the spinal canal; the lesion had invaded the vertebral bones and spread into the extradural space through the intervertebral foramen. (b) Syrinx had developed above the tumor (arrows). (e) Hematoxylin–eosin stain (magnification: ×50) and (f) immune stain of S-100 (magnification: ×50) showing palisading pattern of S-100-positive cells. Bar, 50 μm.