Abstract:Objective: To investigate the distinction of 18F-FDG uptake between osteolytic and osteogenic bone metastases and the correlation between 18F-FDG uptake of bone metastases and different pathological types of lung cancer. Methods: 18F-FDG PET/CT scans were performed in 60 patients who were histologically proved as lung cancer at initial diagnosis with bone metastases. The SUVs of bone metastases were automatically measured by drawing the regions of interest(ROI). The osteolytic or osteogenic bone metastases were definited according to their densities dispalyed in integrated CT. Results: Three hundred and ninety-two bone metastases were confirmed by clinical follow-up, in which 389 bone metastases had intense 18F-FDG uptake. The other three lesions without intense 18F-FDG uptake had intense bone density change on CT. There were 201 lesions of osteolytic bone metastases, 75 of osteogenic bone metastases and 116 without bone density change. The SUV of them were 3.5±1.3, 2.7±0.6, 3.0±1.2, respectively. The SUVs of osteolytic bone metastases were higher than those of the latter two groups(P<0.01), while there were no statistical difference between the latter two groups(P>0.05). The SUVs of bone metastases of adenocarcinoma, squamous carcinoma, big and small cell carcinoma group were 3.4±1.3, 3.1±1.4, 3.3±1.1, 2.5±0.6, respectively. The SUV of small cell lung cancer group was lower than that of adenocarcinoma and big cell lung cancer groups, but no significant difference with squamous carcinoma. There were no significant differences of 18F-FDG uptake between the bone metastase of adenocarcinoma, squamous carcinoma, big and small cell carcinoma groups(P>0.05). Conclusions: The detection rate of bone metastasis of lung cancer in PET is higher than that in integrated CT. The osteolytic bone metastase has a higher FDG uptake than osteogenic ones. The role of PET and integrated CT can complement and confirm each other in the detection of bone metastastatic lesions of lung cancer.