Fig. 2

A A 25-year-old man with primary DFSP in the back. B A 32-year-old female with primary DFSP in the abdominal wall. A1, A2 US showed an ovoid circumscribed subcutaneous lesion with profuse blood flow throughout and hypoechogenicity, forming tentacle-like projections or a “claw” sign (arrow). A3 Hematoxylin-eosin staining showing high cellularity with slender spindle cells arranged in a distinct storiform pattern (H&E, 100×). A4 Immunohistochemical staining was positive for CD-34 (original magnification 200×). B1, B2 US showed a poorly defined hyperechoic mass with restricted blood flow in the subcutaneous soft tissue. The margin of the tumor appeared to have pseudopodial-like protrusions, forming tentacle-like projections or a “claw” sign (arrow). B3 Hematoxylin-eosin staining showing that tumor cells infiltrated into the surrounding subcutaneous fat tissue H&E, 100×). B4 Immunohistochemical staining was positive for CD-34 (original magnification 200×)