Background Intestinal (18)F-FDG Uptake Is Related to Serum Lipid Profile and Obesity in Breast Cancer Patients

BACKGROUND: This study investigated the relationships between background intestinal uptake on (18)F–FDG PET and cardio-metabolic risk (CMR) factors. METHODS: A total of 326 female patients that underwent (18)F–FDG PET to determine the initial stage of breast cancer were enrolled. None of the patients had history of diabetes or hypertension. The background intestinal uptake on PET was visually graded (low vs. high uptake group) and quantitatively measured using the maximal standardized uptake value (SUV(max)). SUV(max) of 7 bowel segments (duodenum, jejunum, ileum, cecum, hepatic flexure, splenic flexure, and descending colon-sigmoid junction) were averaged for the total bowel (TB SUV(max)). Age, body mass index (BMI), fasting blood glucose level (BST), triglyceride (TG), cholesterol, high density lipoprotein (HDL), and low density lipoprotein (LDL) were the considered CMR factors. The relationships between background intestinal (18)F–FDG uptake on PET and diverse CMR factors were analyzed. RESULTS: The visual grades based on background intestinal (18)F–FDG uptake classified 100 (30.7%) patients into the low uptake group, while 226 (69.3%) were classified into the high uptake group. Among CMR factors, age (p = 0.004), BMI (p<0.001), and TG (p<0.001) were significantly different according to visual grade of background intestinal (18)F–FDG uptake. Quantitative TB SUV(max) showed significant positive correlation with age (r = 0.203, p<0.001), BMI (r = 0.373, p<0.001), TG (r = 0.338, p<0.001), cholesterol (r = 0.148, p = 0.008), and LDL (r = 0.143, p = 0.024) and significant negative correlation with HDL (r = -0.147, p = 0.022). Multivariate analysis indicated that BMI and TG were independent factors in both visually graded background intestinal (18)F–FDG uptake (p = 0.027 and p = 0.023, respectively) and quantitatively measured TB SUV(max) (p = 0.006 and p = 0.004, respectively). CONCLUSION: Increased background intestinal (18)F–FDG uptake on PET may suggest alteration of lipid metabolism and risk of cardio-metabolic disease in non-diabetic and non-hypertensive breast cancer patients.