PDGFB and fibrosis: For example, myxoid liposarcoma can detect DDIT3 gene translocation by fluorescence in situ hybridization technique, while PDGFB is negative; (4) DFSP with muscular/myofibroblastic differentiation: Eosinophilic muscular nodules or bundles can provide certain hints for diagnosing this subtype; (5) Atrophic or plaque-type DFSP: Generally presents as skin atrophy, loose skin, or plaques, and the tumor is located in the superficial dermis, making it easy to confuse with dermatofibroma or fibrosis.