Bone Metastases Detection by 18F-FDG PET/CT Versus 99mTc Bone Scintigraphy (Planar and SPECT) in Patients with Lung Cancer

Detection of bone metastases in patients with lung cancer has important clinical significance and therapeutic implications, since it causes relevant changes in the patients’ treatment. This study compared the efficacies of 18F-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT, and 99mTc bone scintigraphy [planar and single photon emission CT (SPECT))for detection of bone metastases in patients with lung cancer. 165 patients with confirmed diagnosis of lung cancer (108 men and 57 women; with a mean age of 58.36 ± 9.14 year) participated in this retrospective study, 153 patients had nonsmall cell lung cancer (NSCLC), and 12 patients had extensive stage small cell lung cancer (SCLC).All the patients underwent a BS and FDG PET/CT scintigraphy with a mean interval between both examinations of 10.23 ± 4.12 days (maximum 45 days). The sensitivity of 99mTc bone scintigraphy (SPECT) was significantly higher than those of 18F-FDG PET/CT and 99mTc bone scintigraphy (planar) (p< 0.05). There were no significant differences among the specificities of these three modalities. The accuracy of 99mTc bone scintigraphy (SPECT) was significantly higher than that of 99mTc bone scintigraphy (planar). In addition, bone metastases were confirmed in 350 metastatic bone lesions, 170 (48.57%) were classified as osteolytic and 140 (40%) as osteoblastic lesions on the basis of the CT images, but 40 (11.43%) could not be classified because of their unclear CT images. The sensitivities of 18F-FDG PET/CT and 99mTc bone scintigraphy (planar) for the osteoblastic lesions were lower than those of 99mTc bone scintigraphy (SPECT). Within the limit of this study single photon emission CT (SPECT) is superior to planar bone scintigraphy and 18F-FDG PET/CT in detecting bone metastasis among patients with lung cancer.