PET scan (Positron Emission Tomography scan)

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A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.


Cancer cells show up as bright spots on PET scans because they have a higher metabolic rate than do normal cells. PET scans may be useful in:

– Detecting cancer
– Revealing whether your cancer has spread
– Checking whether a cancer treatment is working
– Finding a cancer recurrence