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    PET (Positron Emission Tomography) – Cancer Diagnosis

    An important tool for precise diagnosis and disease staging, particularly of cancer. Positron Emission Tomography (PET) detects changes in cellular function. Since these take place before physical changes occur, PET can provide information that allows the physician to make an earlier diagnosis or to determine if current treatment is working effectively.

    PET is a medical test that uses a special type of camera and a tracer to look at organs in the body. The camera takes 3D pictures of functional processes in the body. The tracer usually is a special form of a substance (such as glucose) that collects in cells that are using a lot of energy, such as cancer cells.

    The tracer is normally fed through the veins and then moves through your body, where much of it is collected in specific organs or tissue. The radioactive material may also be inhaled or swallowed depending on the organ or type of tissue examined. The tracer emits tiny positively charged particles (positrons). The camera records the positrons and turns the recording into pictures on a computer.

    The computer generated image is not show as much details so they may be compared with a CT scan for more information.

    PET scans are done to:
    • Evaluate some cancers like head and neck, brain, lung, colon, or prostate. In early stages of cancer, a PET scan can show up more clearly than on a CT scan or an MRI.
    • See how advanced cancer is and whether it has spread to other parts of the body.
    • Choose the best treatment for cancer or to see how well treatment is working. PET scans may also be done to see whether surgery can be done to remove a tumor.

    For more information about cancer treatment and care in the San Francisco Bay Area, call 650-696-4405.