Objective: The objective of this study was to compare the diagnostic accuracy of dual-time-point 18F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) to single-time-point (18)F-FDG PET for staging of preoperative lung cancer.
Methods: Between November 2008 and December 2009, 107 patients who were diagnosed as having lung cancer or strongly suspected of having lung cancer were enrolled. They underwent dual-time-point (18)F-FDG PET following conventional imaging. Dual-time-point (18)F-FDG PET imaging (whole body) was performed at 1-h (early) post-FDG injection and repeated (2 h delayed) after injection. The diagnostic accuracy of pre-PET staging and post-PET staging was retrospectively evaluated, and the diagnostic accuracy of dual-time-point (18)F-FDG PET was compared to that of single-time-point (18)F-FDG PET.
Results: In 100 patients, the early (18)F-FDG PET scan resulted in upstaging of the tumor in ten (10 %) and down-staging of the tumor in five (5 %) compared to the conventional scan. The delayed phase of (18)F-FDG PET provided no additional information on staging for lung cancer patients. The remaining seven patients were diagnosed as not having lung cancer.
Conclusion: This study confirmed that dual-time-point (18)F-FDG PET is useful for differential diagnosis between benign and malignant lesions, but has no major impact on staging and therapeutic management of patients with pathologically proven lung cancer.