PET-CT involves injecting a small amount of radioactive tracer, usually fluorodeoxyglucose (FDG), into the patient's bloodstream. Cancer cells, which typically have higher metabolic rates than normal cells, absorb more of the tracer. The PET scan detects the radiation emitted by the tracer, highlighting areas of high metabolic activity. The CT scan then provides detailed images of the body's internal structures, allowing for accurate localization of these active areas.
