Correlations between SUVmax of 18F FDG PET/CT and Clinical Characteristics in Healthy Subjects

Background: 18 F-FDG PET/CT has been wildly used in cancer screening. However, FDG accumulates not only in malignant lesions but also in inflammatory processes, which are frequently observed in normal subjects. We investigated PET/CT images in healthy subjects and identified the correlation between quantitative values of images and clinical characteristics. Method: 105 subjects undergoing PET/CT scans for health examinations were retrospectively collected. The standardized uptake value (SUVmax) in the nasopharyngeal (NP) region, neck lymph nodes (LNs), palatine tonsil, mediastinal or pulmonary LNs were evaluated. The correlation between the SUVmax and the clinical variables was assessed. Results: There is strong negative correlation between the SUVmax of palatine tonsils and age (p =0.0004), strong positive correlation between the SUVmax of mediastinal LNs and age (p =0.0004). There’s positive correlation between the SUVmax of palatine tonsils and cholesterol (p =0.03), the SUVmax of neck LNs and serum CRP level (p = 0.04). Conclusion: Age may have different effect on SUVmax of palatine tonsils and mediastinal LNs. While serum level of Cholesterol and CRP may be related to higher FDG uptake. Understanding clinical characteristics of subjects may help the interpretation of PET/CT images for cancer screening.