Positron Emission Tomography Scan
An individual with symptoms indicative of cancer may need to have a positron emission tomography (PET) scan to help rule out or diagnose malignancy in their body. This type of scan is a useful way for a patient's doctor to see the chemical activities of different body parts. While positron emission tomography scans can be used to diagnose many conditions, they are often used for cancer screening and detection. A positron emission tomography scan uses a substance referred to as a tracer to help highlight areas of the body that have a metabolic rate that differs from the rest of the cells in the body.
Instead of searching for a physical mass like x-rays, computerized tomography scans, and magnetic resonance imaging scans do, positron emission tomography scans can show changes in the way cells are functioning. Cancerous cells grow and multiply at a much faster rate than healthy cells. Metabolic rate is the speed at which cells metabolize glucose into ATP or usable energy. The tracer used in positron emission tomography scans for cancer detection contains glucose, which causes the prospective area with a faster metabolic rate to light up in the image.