See Figs. 1, 2, and 3.

Fig. 1
figure 1

a Ultrasound image of the mass at the posterior midline at the level of the thoracolumbar junction. b Ultrasound image of the same area with Doppler vascularity

Fig. 2
figure 2

MRI of the thoracolumbar junction. a Coronal T1W MR image, b axial PDW FS MR image, and c sagittal T2W MR image

Fig. 3
figure 3

Histology. a H&E ×20. b S100 immunohistochemistry, ×20