Preliminary study of ¹⁸F-FDG PET/CT in the diagnosis of solitary hypermetabolic lesion of bone

Objective: This study aims to investigate the clinical value of ¹⁸F-FDG PET/CT in diagnosing solitary hypermetabolic lesion of the bone. Methods: Twenty-two patients with solitary FDG uptake in the bone were enrolled. Patient diagnosis was confirmed by biopsy or surgery. PET/CT images were analyzed. Results: Of the 22 patients, 5 had primary bone lymphoma and bone eosinophilic granuloma, 4 had plasma cell myeloma and osteosarcoma, and 2 had Ewing's sarcoma and giant cell tumoroi the bone. The mean SUV_max of bone lesions is 11.08 ± 8.06(2.1-32.6). Nineteen lesions had welldistributed FDG uptake. The other three lesions were unevenly distributed. No significant difference in FDG uptake was found between malignant and benign lesions (SUV_max: 8.86 ± 2.40 vs. 12.12 ± 9.58, respectively; t = -1.241, P = 0.231), and among different kinds of bone lesions (F = 0.296, df = 5, P = 0.908). Syn-modality CT images showed that 17 patients have osteolytic changes,5 of which with sclerosis edge.Some bone lesions presented as 'bow tie sign', 'soap bubble sign', and 'lace sign'. The other 5 patients, 3 with primary bone lymphoma and 2 with osteosarcoma, presented with ossification changes. Otherwise, soft tissue mass was formulated in 17 patients, and periosteal proliferation developed in 4 patients. Conclusion: Syn-modality CT images should be included in the differential diagnosis of solitary hypermetabolic lesion of the bone. (authors)