FIGURE 3.

A 47-year-old man presented with desmoid-type fibromatosis in the left supraclavicular area with recurrence (Group 1). It was misdiagnosed as a pancoast tumor due to lung cancer and a sarcoma of mesenchymal origin, based on preoperative CT and MR, respectively. (A) The contrast-enhanced axial (A) CT image (5-mm reconstruction) shows a huge, lobulated, partially ill-defined mass in the supraclavicular area (^∗). Note the osteoblastic change of the first and second ribs (white arrows) and suspicion of involvement of the left subclavian artery (black arrow). Note the strong and heterogeneous enhancement with central areas of nonenhancing low signal bands (white arrows) and internal signal voids (black arrow) on enhanced T1-weighted axial (B) and sagittal (C) images. FDG PET revealed a hypermetabolic mass with a maximal standardized uptake value of 4.1 (not shown). (D) The mass was excised. Pathologically, the mass has infiltrated the brachial plexus, and tumor cells surround the nerve bundles (arrows, ×12.5 magnification). CT = computed tomography, MR = magnetic resonance, FDG PET = ¹⁸F-fluorodeoxy glucose positron emission tomography.