Likely Common Role of Hypoxia in Driving 18F-FDG Uptake in Cancer, Myocardial Ischemia, Inflammation and Infection

First introduced in 1976, F-18-fluorodeoxyglucose (F-18-FDG) positron emission tomography (PET) has become an indispensable tool for diagnosis and prognostic evaluation of tumors, heart disease, as well as other conditions, including inflammation and infection. Because F-18-FDG can accurately reflect the glucose metabolism level of organs and tissues, it is known as a "century molecule" and is currently the main agent for PET imaging. The degree of F-18-FDG uptake by cells is related to both the rate of glucose metabolism and glucose transporter expression. These, in turn, are strongly influenced by hypoxia, in which cells meet their energy needs through glycolysis, and F-18-FDG uptake increased due to hypoxia. F-18-FDG uptake is a complex process, and hypoxia may be one of the fundamental driving forces. The correct interpretation of F-18-FDG uptake in PET imaging can help clinics make treatment decisions more accurately and effectively. In this article, we review the application of F-18-FDG PET in tumors, myocardium, and inflammation. We discuss the relationship between F-18-FDG uptake and hypoxia, the possible mechanism of F-18-FDG uptake caused by hypoxia, and the associated clinical implications.