Fig. 25

Synovial sarcoma of deep epaxial muscles at C4 level in a 53-year-old male with a bump and acute non-mechanical cervical pain. The mass presents aggressive radiological features such as cortical and trabecular lysis of the neural arch of C4 (a) with moth-eaten margin. The mass has low intensity on T1WI (b), with enhancement on contrast-enhanced fat-suppressed T1WI (c) and high signal on T2WI (d). MRI features suggestive of bone invasion were: the disappearance of the fat plane separating the mass and the lamina (black arrow, c) the enhancement of medullary bone of the spinous process (white arrowhead, d) and the enhancement of periosteum of right lamina (black arrowhead, d). Lateral radiograph of the surgical sample (two-third vertebrectomy) (e) shows bone lysis of the tip of the vertebral processes (C4, C5 and C6) (white arrows). The yellow star shows the epicentre of the mass.