Diagnostic Value of 18F-FDG PET/CT in Comparison to Bone Scintigraphy, CT and 18F-FDG PET for the Detection of Bone Metastasis


Purpose: To evaluate the diagnostic value of 18F-FDG PET/CT for detection of bone metastasis in comparisonwith the efficacies of 18F-FDG PET/CT, CT, 18F-FDG PET and conventional planar bone scintigraphy in a seriesof cancer patients.
Methods: Five hundred and thirty patients who underwent both 18F-FDG PET/CT and bonescintigraphy within 1 month were retrospectively analyzed. The skeletal system was classified into 10 anatomicsegments and interpreted blindly and separately. For each modality, the sensitivity, specificity, accuracy, PPVand NPV were calculated and the results were statistically analyzed.
Results: Bone metastases were confirmedin 117 patients with 459 positive segments. On patient-based analysis, the sensitivity, specificity, accuracy, PPVand NPV of 18F-FDG PET/CT were significantly higher than bone scintigraphy, CT and 18F-FDG PET (P<0.05).On segment-based analysis, the sensitivity of CT, bone scintigraphy, 18F-FDG PET and 18F-FDG PET/CT were70.4%, 89.5%, 89.1% and 97.8%, respectively (P<0.05, compared with 18F-FDG PET/CT). The overall specificityand accuracy of the four modalities were 89.1%, 91.8%, 90.3%, 98.2% and 90.3%, 90.9%, 89.8%, 98.0%,respectively (P<0.05, compared with 18F-FDG PET/CT). The PPV and NPV were 89.8%, 87.6%, 85.6%, 97.2%and 85.6%, 93.2%, 92.8%, 98.6%, respectively. Three hundred and twelve lesions or segments were presentedas lytic or sclerotic changes on CT images at the corresponding sites of increased 18F-FDG uptake. In lytic ormixed lesions, the sensitivity of 18F-FDG PET/CT and 18F-FDG PET were better than bone scintigraphy, whilein osteoblastic lesions bone scintigraphy had a similar performance with 18F-FDG PET/CT but better than18F-FDG PET alone.
Conclusion: Our data allow the conclusion that 18F-FDG PET/CT is superior to planar bonescintigraphy, CT or 18F-FDG PET in detecting bone metastasis. 18F-FDG PET/CT may enhance our diagnosis oftumor bone metastasis and provide more information for cancer treatment.