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    Sentinel Lymph Node Biopsy

    How It Feels

    You may feel a sharp sting or burn from the medicine used to numb the biopsy site or from the dye or tracer. Feeling pressure or warmth during the biopsy is normal, but you should feel little or no pain. If you have pain, tell your doctor. If you feel like you are having an allergic reaction, tell your doctor. This can happen with the dye used for this biopsy.

    If you have general anesthesia, you may feel drowsy for several hours after the biopsy. You may have a mild sore throat from the tube used to help you breathe during the biopsy. Throat lozenges and gargling with warm salt water may help soothe your sore throat. You may get medicine at the biopsy site that will help with the pain for 6 to 12 hours. You may have more pain after this medicine wears off.

    The biopsy site may be sore for several days. A small amount of bleeding is normal. Ask your doctor how much drainage to expect. Call your doctor immediately if you have:

    • An increase in pain, redness, or swelling at the biopsy site.
    • A fever.
    • An increase in bleeding or drainage, such as pus.
    • Any swelling in your arm.


    It is possible to have some problems after a biopsy. Your doctor will give you instructions on what to do if a problem occurs.

    • Bleeding from the biopsy site. This risk is higher for people who have bleeding problems or who take blood-thinning medicines. If you are at risk for bleeding, you may be given blood clotting factors before the biopsy.
    • Skin numbness at the biopsy site
    • Infection at the biopsy site
    • Swelling and fluid buildup (lymphedema). This is less likely after a sentinel node biopsy than if more lymph nodes are taken out (axillary dissection).
    • Problems from general anesthesia, if it is used
    • Damage to nerves at the biopsy site. This may cause weakness or pain.


    A sentinel lymph node biopsy is a surgery that takes out lymph node tissue to look for infection or cancer. Test results from are usually available within a few days.

    The lymph node tissue is usually treated with special dyes (stains) that color the cells so problems can be clearly seen.

    Sentinel lymph node biopsy

    The dye or tracer flows evenly to the sentinel lymph node.

    The lymph node has normal numbers of lymph node cells.

    The structure of the lymph node and the cells look normal.

    No cancer is present.


    The dye or tracer does not flow evenly to the sentinel lymph node.

    The sentinel lymph node cannot be identified.

    Cancer cells may be seen. Cancer cells may start in the lymph nodes, such as in Hodgkin's lymphoma. Cancer cells may have spread, or metastasized, from other sites, such as in breast cancer or melanoma.

    WebMD Medical Reference from Healthwise

    Last Updated: November 14, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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