The present study has clearly shown that fibroblast-like spindle tumour cells strongly express FAP and DPP-IV in low-grade myofibroblastic sarcoma, fibroblastic areas of osteosarcoma, MFH, non-ossifying fibroma, desmoid tumour, and chondroblastoma. The gene discussed is FAP; the disease is undifferentiated pleomorphic sarcoma.