A Study on the Diagnostic Value of 99mTc-FAPI Quantitative SPECT/CT Imaging in Adult Solitary Bone Lesions

Inclusion Criteria: * Benign solitary bone lesions in adults (fibrous cortical defects, fibrous hyperplasia, non-ossifying fibroma, osteoblastoma, osteoid osteoma, osteochondroma, etc.); Malignant solitary bone lesions in adults (osteosarcoma, Ewing's sarcoma, chondrosarcoma, malignant giant cell tumour of bone, etc.); Other fibroblast-rich bone lesions (chordoma, alveolar soft part sarcoma, fibrosarcoma, malignant fibrous histiocytoma, etc.). Exclusion Criteria: * Severe liver and kidney dysfunction; Pregnant women and breastfeeding patients; Patients in poor physical condition who cannot tolerate the examination; Patients who cannot cooperate to complete the examination; Patients under the age of 18.