A sentinel node biopsy is a procedure to test if cancer has spread beyond the original tumor. It’s most commonly used in people with breast cancer and melanoma. During the procedure, healthcare providers remove small organs called sentinel nodes and test them for cancer cells. The results help providers determine the most appropriate treatments.
A sentinel node biopsy (sentinel lymph node biopsy) is a surgical procedure for people withcancer. During the procedure, a healthcare provider removes one or more sentinel nodes and sends them to a lab to test for cancer cells. The results show if cancer has spread beyond the original (primary)tumor.
Yourlymph nodes are small, bean-shaped glands that filter fluid in your body and help protect you from illness. You have about 600 lymph nodes throughout your body. They trap harmful substances, including viruses, bacteria and cancer cells.
Sentinel nodes are the first lymph nodes where cancer cells might spread from a tumor. This is why providers test your sentinel nodes for signs of cancer spread.
Providers primarily use sentinel node biopsy during cancer staging inbreast cancer andmelanoma. Cancer staging allows providers to determine whether cancer is spreading and how advanced it is. A sentinel node biopsy can also help stage penile or uterine cancer (endometrial cancer).
Researchers and healthcare providers are researching whether they can use it to stage other cancers as well, including:
Healthcare providers usually perform this procedure while they’re removing the tumor. Sometimes, healthcare providers do a sentinel node biopsy before or after removing the primary tumor.
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Before a sentinel lymph node biopsy, a provider will inject a special dye around the cancer site to determine which lymph nodes are the main draining lymph nodes. This means that if the cancer were to spread, it would spread to these lymph nodes first.
During a sentinel node biopsy, a surgeon locates your sentinel nodes, removes them and sends them to a lab for testing. A different provider tests the nodes for cancer cells.
Follow your healthcare provider’s guidance on how to prepare. You may receive instructions related to:
Arrange to have someone drive you home on the day of your procedure.
Before or during surgery, you may receive an injection of a safe radioactive substance (tracer) and/or a dye that travels the same path that fluid draining from your tumor would take. The tracer leads your surgeon to your sentinel lymph node(s).
You’ll receive generalanesthesia through an IV (a needle in your arm) that will put you to sleep so you don’t feel any pain. Once you’re asleep, your healthcare provider will:
Afterward, they’ll send the sentinel nodes to a lab, where a pathologist will test for cancer cells. A pathologist is an expert in diagnosing medical conditions using lab tests.
It depends. Your healthcare provider will remove enough sentinel nodes to accurately detect cancer cells. Most providers remove more than one, but the ideal number is debatable. Some studies show that removing three sentinel nodes is often enough to detect cancer. Other research shows that up to five may need to be removed for an accurate diagnosis.
The numbers vary for every person based on their unique case.
Many people have someone drive them home the same day, but you may need to stay in the hospital overnight. Follow your healthcare provider’s advice on when it’s safe to leave.
As you heal, you can expect the following, which are all normal:
Before leaving the medical facility, ensure you know how to care for the incision site and understand what potential complications to look out for. Ask when it’s safe to return to your regular activities. Recovery time for a sentinel node biopsy varies, but most people need to wait several weeks before running, exercising or lifting.
A sentinel node biopsy is a safe procedure. Still, every surgery poses some risks. Potential side effects and complications include:
Contact your healthcare provider immediately if you notice signs of these complications.
Results are either positive or negative. A negative result means that there’s no sign of cancer in your sentinel nodes. It’s unlikely that cancer has spread to other lymph nodes. Positive results mean that the biopsy did detect cancer cells in your lymph node(s).
If your results come back positive, your healthcare provider may recommend removing other lymph nodes (not just sentinel nodes) to check for cancer spread. They may recommend additional treatments. Your healthcare provider will advise you on the next steps based on your unique diagnosis.
You may receive results as soon as that same day, or it may take up to a few weeks. If your test results come back positive that same day, your healthcare provider may remove more lymph nodes for testing. That way, you don’t have to return for surgery. It may take longer to receive results if the surgeon needs to discuss results with your cancer care team.
Call your healthcare provider if you have any signs of a complication, including:
You won’t feel any pain during the procedure, as you’ll be asleep. Most people manage pain in the days after with over-the-counter medicines and icing the area. Few may need prescription pain medications. Talk to your healthcare provider about medicine to help with the pain while your incision heals.
A note from Cleveland Clinic
A sentinel node biopsy provides essential information about how advanced your cancer is. The risks of this surgical procedure are low, and most people recover quickly. If cancer cells aren’t in your sentinel nodes, it’s a good sign that cancer hasn’t spread beyond your tumor site. Positive results provide important information your healthcare provider can use to plan the most effective treatment for you.
Last reviewed by a Cleveland Clinic medical professional on 09/08/2023.
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