Cancer screening is a major healthcare issue. Screening modalities are constantly changing due to improvements in technology. Whole body positron emission tomography (PET) with 18F-fluoro-2 deoxy-D-glucose (FDG) and the additional help of the serum levels of tumor markers have been considered as non-invasive methods for cancer screening in asymptomatic subjects. A total of 1283 subjects underwent whole-body FDG PET studies with the additional help of the serum levels of tumor markers in our center for cancer screening. The final diagnoses were confirmed by other imaging modalities or pathological findings in subjects with positive FDG-PET findings, and follow-up for at least 6 months were held in subjects with negative FDG-PET findings. Among a total of 18 (1.4%) subjects with cancers, FDG-PET detected cancers in 15 (1.2%) subjects but with false negative studies in 3 subjects with hepatoma (AFP = 129.6 ng/ml), prostate cancer (PSA = 25.1 ng/ml), and breast cancer (CEA and CA-153 were normal). False-positive FDG-PET studies were found in 24 (1.9%) subjects. However, none had abnormal serum levels of tumor markers. Whole body FDG-PET with the additional help of tumor markers could reduce the false negative and false positive results of FDG-PET only.