A number of economic evaluation studies overseas have shown that PET is cost-effective in NSCLC when added to conventional work-up. However, due to that the sensitivity and specificity of 18F-FDG PET in staging NSCLC, the cost structure of medical expense, the severity of disease for NSCLC patients when they first present in the hospital, may be different between different countries. To the best of our knowledge, there has been no report that provides a practical guide to introduce PET in staging NSCLC. A cost-effectiveness economic evaluation in Taiwan is thus in demand.