Comparative effectiveness: 18F-FDG-PET/CT versus CT for post-treatment follow-up of patients with lung cancer.

Purpose: This study aimed to evaluate the comparative effectiveness of follow-up fluorine-18-fluorodeoxyglucose (F-FDG)-PET/CT and chest CT in the detection of local, regional, and distant metastatic diseases in lung cancer.
Patients and Methods: Follow-up F-FDG-PET/CT and chest-CT pairs of biopsy-proven lung cancer patients were reviewed retrospectively (May 2004-June 2013). Histopathological, clinical, or imaging follow-up data of at least 6 months was considered the reference standard. The κ statistics, the percentage agreement between the two techniques, and per-scan basis diagnostic performances were reported.
Results: A total of 270 patients with a total of 423 paired F-FDG-PET/CT and chest-CT scans were included (median time interval between two scans=2 days). The two imaging modalities showed concordance of 82.7% (κ=0.71) for local disease, 82% (κ=0.65) for regional disease, and 77.3% (κ=0.55) for distant metastasis. Overall, F-FDG-PET/CT identified more lesions compared with chest CT both in the regional lymph nodes (308 vs. 204 regional zone involvement) and in cases of distant metastasis (253 vs. 182 metastatic sites). In the evaluation of local disease, F-FDG-PET/CT appeared to have fairly similar sensitivity (96 vs. 95.4%) and specificity (82.1 vs. 83%) compared with chest CT. In the evaluation of regional lymph nodes and distant metastases, F-FDG-PET/CT showed higher sensitivity (regional nodes: 96 vs. 89.8%; distant metastases: 91.9 vs. 70.7%) and comparable specificity (regional nodes: 87.1 vs. 88.9%; distant metastases: 87.1 vs.88.1%).
Conclusion: The sensitivity of F-FDG-PET/CT is superior to that of chest CT in the detection of regional and distant metastasis, while having comparable specificity.