title: Dual time point 18FDG-PET/CT versus single time point 18FDG-PET/CT for the differential diagnosis of pulmonary nodules: a meta-analysis.
abstract: BACKGROUND
  Lung cancer is one of the most common cancer types in the world. An accurate diagnosis of lung cancer is crucial for early treatment and management.
  
  
  OBJECTIVE
  To perform a comprehensive meta-analysis to evaluate the diagnostic performance of dual time point 18F-fluorodexyglucose position emission tomography/computed tomography (FDG-PET/CT) and single time point 18FDG-PET/CT in the diagnosis of pulmonary nodules.
  
  
  METHODS
  PubMed (1966-2011.11), EMBASE (1974-2011.11), Web of Science (1972-2011.11), Cochrane Library (-2011.11), and four Chinese databases - CBM (1978-2011.11), CNKI (1994-2011.11), VIP (1989-2011.11), and Wanfang Database (1994-2011.11) - were searched. Summary sensitivity, summary specificity, summary diagnostic odds ratios (DOR), and summary positive likelihood ratios (LR+) and negative likelihood ratios (LR-) were obtained using Meta-Disc software. Summary receiver-operating characteristic (SROC) curves were used to evaluate the diagnostic performance of dual time point 18FDG-PET/CT and single time point 18FDG-PET/CT.
  
  
  RESULTS
  The inclusion criteria were fulfilled by eight articles, with a total of 415 patients and 430 pulmonary nodules. Compared with the gold standard (pathology or clinical follow-up), the summary sensitivity of dual time point 18FDG-PET/CT was 79% (95%CI, 74.0-84.0%), and its summary specificity was 73% (95%CI, 65.0-79.0%); the summary LR+ was 2.61 (95%CI, 1.96-3.47), and the summary LR- was 0.29 (95%CI, 0.21-0.41); the summary DOR was 10.25 (95%CI, 5.79-18.14), and the area under the SROC curve (AUC) was 0.8244. The summary sensitivity for single time point 18FDG-PET/CT was 77% (95%CI, 71.9-82.3%), and its summary specificity was 59% (95%CI, 50.6-66.2%); the summary LR+ was 1.97 (95%CI, 1.32-2.93), and the summary LR- was 0.37 (95%CI, 0.29-0.49); the summary DOR was 6.39 (95%CI, 3.39-12.05), and the AUC was 0.8220.
  
  
  CONCLUSIONS
  The results indicate that dual time point 18FDG-PET/CT and single time point 18FDG-PET/CT have similar accuracy in the differential diagnosis of pulmonary nodules. Dual time point 18FDG-PET/CT appears to be more specific than single time point 18FDG-PET/CT.
authors.affiliation: The First Clinical Medical School of Lanzhou University.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Yinzhong
authors.initials: Y
authors.lastname: Wang
authors.forename: Junqiang
authors.initials: J
authors.lastname: Lei
authors.forename: Jinhui
authors.initials: J
authors.lastname: Tian
authors.forename: Yanan
authors.initials: Y
authors.lastname: Zhai
mesh_terms: D003937:Diagnosis, Differential; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: PET/CT; Pulmonary nodule; diagnosis; meta-analysis