The Effect of Glucose on Quality of PET Scan Results

Positron Emission Tomography (PET) imaging is a metabolic imaging technique using a radioactive tracer, 18F-fluorodeoxyglucose (18F-FDG), to identify the presence and severity of disease, namely cancers. Most malignant tissues have increased 18F-FDG uptake associated with an increased rate of glycolysis and of glucose transport. The increase in 18F-FDG uptake noted in malignant tissues is related in a complex manner to the proliferative activity of malignant tissue and information regarding the location of abnormal levels of radioactive glucose obtained from a PET scan helps clinicians effectively pinpoint sources of cancer and progression of disease. According to the 2011 census, a total of 1,853,700 clinical PET and PET/CT studies were performed at over 2,200 U.S. locations[1]. Appropriate patient preparation plays an important role in obtaining good quality images, which is essential for accurate interpretation as the concentration of circulating glucose can significantly affect 18F-FDG uptake by tumors. Relevant considerations before the study include restrictions of diet and activity, management blood glucose levels in patients with diabetes, as well as an awareness of the effect of medications and environmental conditions. Important protocol guidelines for performing PET and PET/CT have been proposed by various societies and groups, including the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Nuclear Medicine (EANM), the American College of Radiology (ACR), the National Cancer Institute (NCI), and the Netherlands society of nuclear medicine.