18F-Labeled NaF PET-CT in Detection of Bone Metastases in Patients With Preoperative Lung Cancer

We compared the diagnostic accuracy of F-labeled sodium fluoride (F-NaF) PET-CT with 99m-technetium methylene diphosphonate (Tc-MDP) single photon emission computed tomography (SPECT) to detect bone metastases (BMs) in patients with preoperative lung cancer. Patients with lung cancer (n = 181) were examined with F-NaF PET-CT, and another 167 patients with lung cancer were examined with Tc-MDP SPECT. F-NaF PET-CT and Tc-MDP SPECT were evaluated by 2 experienced readers. Lesions were graded on a scale of 0 (degenerative lesion) to 4 (definite BM), and equivocal lesions were determined as indifferent (grade 3). Based on patient-based analysis, there were only 4 equivocal patients in F-NaF PET-CT detection. However, in Tc-MDP SPECT detection, there were 19 equivocal patients, which indicated a significant difference in terms of occurrence ratio (χ = 9.005, P = 0.03). Sensitivity and specificity of PET-CT was significantly better than that of SPECT when equivocal reading was categorized as malignant or benign (P < 0.05). Based on lesions-based analysis, SPECT produced 26 equivocal lesions of 333 lesions, but PET-CT produced only 5 equivocal lesions of 991 lesions. PET-CT was significantly better than SPECT in the aspect of producing equivocal patients (χ = 58.141, P < 0.001). Sensitivity and specificity of PET-CT was significantly better than that of SPECT when equivocal reading was categorized as malignant or benign (P < 0.05). F-NaF PET-CT is a highly sensitive and specific modality for the detection of BM in patients with preoperative lung cancer. It is better than conventional Tc-MDP SPECT in detecting BM in patients with preoperative lung cancer.