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Sentinel Lymph Node Biopsy

NC Surgery Lifestyle Image Doctor examining patient shoulder and armLymph nodes are part of the body's lymphatic system. Groups of these organs are found in areas like the neck, underarms and groin. They transport fluid that provides the body's cells with oxygen and nutrients and removes waste from the body's tissues.

Lymph nodes also contain immune system cells that monitor the fluid for substances like bacteria and viruses. They also help determine if some cancers, mainly breast and melanoma, have begun to spread.

One of the earliest places cancers spread from a tumor to the rest of the body is through lymph nodes. The first nodes to which they spread are called sentinel nodes. To find out if a cancer has spread, your doctor may perform sentinel lymph node mapping and biopsy. Focusing solely on the sentinel nodes - typically one or two - is less invasive than removing all of the lymph nodes in an area and reduces the opportunity for side effects and harm.


  • During sentinel mapping, a doctor injects a radioactive tracer and blue dye near a tumor.
  • The fluids drain from the tumor to the sentinel nodes, allowing a surgeon to identify which node or nodes are the main ones.
  • A device is used to scan for radioactivity around the nodes. The device beeps when it nears the sentinel nodes, telling the surgeon where to make an incision.
  • After the small incision is made, the surgeon can see where the dyed nodes are.
  • The node or nodes are removed and are checked for cancer cells. If the result is negative, it is likely the cancer has not spread. If it is positive, the surgeon may remove the other lymph nodes in the area.
  • The procedure may be done on an outpatient basis or with a short hospital stay.

After Surgery

There are some potential side effects of sentinel lymph node surgery including:

  • Lymphedema, or a buildup of fluid in the remaining nodes, causing pain, swelling or hardened skin at the surgery site
  • Numbness or tingling at the surgery location
  • Difficulty moving the arm or leg near the surgery site
  • Bruising
  • Infection
  • An allergic reaction to the dye
  • A false-positive from the biopsy

Our Physicians

North Carolina Surgery is a leader in breast care, providing convenient, timely, personalized services. No matter where you are located, we have offices nearby - in Raleigh, Wakefield, Garner and Knightdale. Our experts will be there with you during your entire journey, from examination and counseling to surgery and follow-up treatment.


For more information on a sentinel lymph node biopsy, visit the National Cancer Institute or the American Cancer Society.

Make an Appointment

To make an appointment, or to speak with someone on our staff, please call 919-784-4160.

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