NEW RADIOTRACER ----FLUOROGLUTAMINE
FDG is the only metabolic imaging agent approved by the US Food and Drug Administration for the detection and monitoring of tumors. However, up to 30% of active tumors have negative FDG uptake, making them untraceable with FDG-PET
"These negative FDG-PET scans suggest there is an alternative source of energy and nutrients, such as glutamine, which sustains tumor growth and proliferation,"
"Alteration and reprogramming of gene expression appears to be a strategy, which redirects the tumor cell to use glutamine as the energy source to keep the tumor thriving," making it traceable with isotope fluorine-18-labeled glutamine or fluoroglutamine
The glutamine, labeled with the positron-emitting radioactive isotope fluorine-18, could "serve as a new metabolic marker for probing glutamine-addictive tumors not detected by FDG-PET," said investigator Hank Kung, PhD, emeritus professor of radiology at the University of Pennsylvania
Dr. Kung and his team injected fluoroglutamine 100 µg intravenously in 5 patients with gliomas, which included 5 low-grade tumors and 1 transformed high-grade tumor.
Results suggest that fluoroglutamine is a "much-needed noninvasive biomarker for distinguishing aggressive high-grade glioma from benign low-grade glioma,"
Acoording to Dr. DeBerardinis "the brain, in particular, is an extremely avid glucose consumer. So even though gliomas take up FDG, there is often not enough contrast to image the tumor above the background signal. Alternative PET probes, like the glutamine analog may provide a solution to that problem,"
Dr. Kung opines that Fluoroglutamine might be useful for imaging other types of tumors also.
REFERENCE ----European Congress of Radiology (ECR) 2014
