Figure 4: Axial contrast enhanced CT images of the lower and upper thorax in a 37-year-old female with metastatic synovial sarcoma at baseline ((a) and (c)) and following 2-month therapy ((b) and (d)). The 5.6 cm left sided paravertebral mass which was causing destruction of the posterior rib ((a), arrow) showed a dramatic reduction in size with only a thin plaque of indeterminate low attenuation tissue remaining at this site ((b), arrow). A further site of disease behind the right clavicle ((b), arrow) reduced in size from 6.5 cm to 3.6 cm ((d), arrow).