title: Comparison of Positron Emission Tomography Using 2-[18F]-fluoro-2-deoxy-D-glucose and 3-deoxy-3-[18F]-fluorothymidine in Lung Cancer Imaging.
abstract: BACKGROUND
  The detection of solitary pulmonary nodules (SPNs) that may potentially develop into a malignant lesion is essential for early clinical interventions. However, grading classification based on computed tomography (CT) imaging results remains a significant challenge. The 2-[18F]-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET)/CT imaging produces both false-positive and false-negative findings for the diagnosis of SPNs. In this study, we compared 18F-FDG and 3-deoxy-3-[18F]-fluorothymidine (18F-FLT) in lung cancer PET/CT imaging.
  
  
  METHODS
  The binding ratios of the two tracers to A549 lung cancer cells were calculated. The mouse lung cancer model was established (n = 12), and micro-PET/CT analysis using the two tracers was performed. Images using the two tracers were collected from 55 lung cancer patients with SPNs. The correlation among the cell-tracer binding ratios, standardized uptake values (SUVs), and Ki-67 proliferation marker expression were investigated.
  
  
  RESULTS
  The cell-tracer binding ratio for the A549 cells using the 18F-FDG was greater than the ratio using 18F-FLT (P < 0.05). The Ki-67 expression showed a significant positive correlation with the 18F-FLT binding ratio (r = 0.824, P< 0.01). The tumor-to-nontumor uptake ratio of 18F-FDG imaging in xenografts was higher than that of 18F-FLT imaging. The diagnostic sensitivity, specificity, and the accuracy of 18F-FDG for lung cancer were 89%, 67%, and 73%, respectively. Moreover, the diagnostic sensitivity, specificity, and the accuracy of 18F-FLT for lung cancer were 71%, 79%, and 76%, respectively. There was an obvious positive correlation between the lung cancer Ki-67 expression and the mean maximum SUV of 18F-FDG and 18F-FLT (r = 0.658, P< 0.05 and r = 0.724, P< 0.01, respectively).
  
  
  CONCLUSIONS
  The 18F-FDG uptake ratio is higher than that of 18F-FLT in A549 cells at the cellular level. 18F-FLT imaging might be superior for the quantitative diagnosis of lung tumor tissue and could distinguish lung cancer nodules from other SPNs.
authors.affiliation: Department of Hospital Management, The First Affiliated Hospital of Chinese PLA General Hospital, Beijing 100048, China.
authors.forename: Fu-Li
authors.initials: FL
authors.lastname: Wang
authors.affiliation: Department of Radiology, Xuzhou Center Hospital, Xuzhou, Jiangsu 221000, China.
authors.forename: Ye-Ying
authors.initials: YY
authors.lastname: Tan
authors.affiliation: Department of Hospital Management, The First Affiliated Hospital of Chinese PLA General Hospital, Beijing 100048, China.
authors.forename: Xiang-Min
authors.initials: XM
authors.lastname: Gu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Chinese PLA General Hospital, Beijing 100048; Department of Radiology, Nanjing General Hospital of Chinese PLA, Nanjing, Jiangsu 210000, China.
authors.forename: Tian-Ran
authors.initials: TR
authors.lastname: Li
authors.affiliation: Department of Radiology, Nanjing General Hospital of Chinese PLA, Nanjing, Jiangsu 210000, China.
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Lu
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Chinese PLA General Hospital, Beijing 100048, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: Department of Radiology, Peking University People's Hospital, Beijing 100048, China.
authors.forename: Tian-Long
authors.initials: TL
authors.lastname: Huo
mesh_terms: D000072283:A549 Cells; D000818:Animals; D019788:Fluorodeoxyglucose F18 / Q000032:analysis*; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18