What is FDG-PET?
The rationale for the use of FDG-PET relies on the difference in basic energy requirements between tumor and normal cells, i.e., tumor cells require more energy to survive and spread. For this procedure, the patient is injected with FDG – a molecule very similar to glucose (a type of sugar), but with a radioactive tracer (F18) attached to it – and then is imaged in a PET machine. Tumor cells, particularly those from especially aggressive tumors, will consume significantly larger amounts of the FDG than normal cells from surrounding tissue. The result is that FDG’s presence can be detected by PET imaging in tumors as small as one centimeter. Researchers have been investigating whether FDG-PET results can predict treatment response early (in the first two to six weeks) after treatment. In these studies, the levels of “tumor uptake” of FDG are measured before treatment and then again a short time later to see if that uptake has decreased, which would signal a decline in the number of tumo
