Introduction: The 2-[18F]-Fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) has become an imaging tool for clinical assessment of tumor, node, metastasis in non-small-cell lung cancer (NSCLC). Primary tumor maximum standardized uptake value (SUV(max)) on (18)F-FDG PET/CT before and after radiation therapy (RT) has been studied as a potential prognostic factor for NSCLC patients receiving radiotherapy. However, the sample sizes of most studies were small, and the results of the prediction value of SUV(max) remained undetermined, which lead us to perform a meta-analysis to improve the precision in estimating its effect.
Methods: We performed a meta-analysis of published literature for primary tumor SUV(max)-based biomarkers of the outcome of NSCLC receiving radiotherapy. The required data for estimation of individual hazard ratios (HRs) to compare patients with a low and a high SUV(max) were extracted from each publication. A combined HR was calculated by Stata statistical software (Version 11). All of the results were verified by two persons to ensure its accuracy.
Results: Thirteen studies were finally included into this meta-analysis; data are available in 13 studies for pre-RT primary tumor SUV(max) and in five studies for post-RT. For overall survival, the combined HR estimate was 1.05 (95% confidence interval [CI], 1.02-1.08) and 1.32 (95% CI, 1.15-1.51) for pre-RT SUV(max) and post-RT SUV(max), respectively; 1.26 (95% CI, 1.05-1.52) and 2.01 (95% CI, 1.16-3.46) for local control (LC). In stereotactic body radiotherapy (SBRT) group, HR for LC was 1.11 (95% CI, 1.06-1.18) and 2.19 (95% CI, 1.34-3.60) for pre-SBRT SUV(max) and post-SBRT SUV(max), respectively.
Conclusion: Both pre-RT and post-RT primary tumor SUV(max) can predict the outcome of patients with NSCLC treated with radiotherapy. Patients with high levels of pre-RT SUV(max) seemed to have poorer overall survival and LC.