Figure 7d. Rhabdomyosarcoma in a 17-year-old girl. Fast SE STIR whole-body MR images obtained at initial staging demonstrate diffusely increased marrow signal intensity in the central skeleton (marrow infiltration proved with biopsy) and additional focal lesions in the distal femora (arrows in b). The paraspinal soft-tissue mass seen at the thoracoabdominal junction (arrowheads in c) was thought to represent the primary tumor. Enlarged lymph nodes are shown in the retroperitoneum and mediastinum (arrows in a, d).