Figure 1. Leiomyosarcoma in a 49-year-old woman. Sagittal T1-weighted (repetition time msec/echo time msec = 600/12) MR image of the spine, obtained after administration of gadolinium-based contrast material, shows a soft-tissue mass with heterogeneous enhancement. Note the enhanced rim or periphery and the central area of low signal intensity. Invasion of the surrounding muscle (arrow) was confirmed at microscopic evaluation of a tissue specimen.