Diagnostic value of dual time-point 18 F-FDG PET/CT versus single time-point imaging for detection of mediastinal nodal metastasis in non-small cell lung cancer patients: a meta-analysis.

BACKGROUND: Lymph node staging in non-small cell lung cancer (NSCLC) is challenging and important for determining treatment policy. Conflicting results have been presented to date.
PURPOSE: To evaluate the diagnostic performance of dual time-point (DTP) 18 F-FDG PET/CT compared with single time-point (STP) imaging for detecting mediastinal nodal metastases in patients with NSCLC.
MATERIAL AND METHODS: The PubMed, EMBASE, EBSCO, and Web of Knowledge databases were searched for relevant articles. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated using Meta-Disc software. Summary receiver-operating characteristic (SROC) curves were also constructed. The potential for between-study heterogeneity was explored using subgroup analyses.
RESULTS: A total of eight studies involving 654 patients fulfilled the inclusion criteria. On a per-patient analysis, the pooled sensitivity and specificity with a 95% confidence interval (CI) for DTP PET/CT were 0.85 (0.78-0.91), 0.75 (0.68-0.82), and for STP imaging, they were 0.79 (0.70-0.85), 0.73 (0.65-0.79), respectively. On a per-lesion basis, the corresponding values for DTP imaging were 0.84 (0.81-0.86), 0.89 (0.87-0.91), and for STP imaging, they were 0.84 (0.80-0.86), 0.83 (0.81-0.85), respectively.
CONCLUSION: DTP PET/CT performed better than STP imaging in evaluating the lymph node status of NSCLC patients and had the potential to be broadly applied in clinical practice. However, due to the small sample size and large heterogeneity, current evidence does not justify the implementation of DTP imaging in routine PET protocols for mediastinal lymph node staging of NSCLC. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.