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.
Purpose: 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.
Material and 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.
Conclusion: 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.
Keywords: PET/CT; Pulmonary nodule; diagnosis; meta-analysis.