If the cancer has spread to the lymph nodes in your armpit you may need further surgery

Breast cancer can sometimes spread to the lymph nodes in your armpit. You will have tests to check for this before surgery, and sometimes during surgery. Lymph nodes are glands found in your armpit and other areas of your body that are part of your immune system.

If you have been diagnosed with Ductal Carcinoma in Situ (DCIS), your lymph nodes may not need to be checked for cancer unless you are having a mastectomy or your breast care team decides there is a high chance of it developing into invasive breast cancer.

What tests will I have?

Ultrasound and biopsy

Before your surgery, your armpit (also known as the axilla) will be checked for cancer using ultrasound imaging. A needle may also be used to remove a small sample (biopsy) from your armpit for testing. If these tests show that the cancer has spread to your armpit, the affected lymph nodes will be removed during your surgery.

If an ultrasound does not detect signs of cancer in your armpit, the lymph nodes will be checked in more detail during surgery to make sure they’re clear of cancer. There are two alternative techniques used to check the armpit lymph nodes during surgery: sentinel lymph node biopsy and axillary node sampling.

Sentinel lymph node biopsy

This is the most common technique used during surgery. Before your surgery a coloured dye and a radioactive solution (with a very low dose of radioactivity) will be injected into your breast. Your surgical team will then track these solutions as they move towards the lymph nodes, and identify the first node reached, known as the sentinel lymph node. Sometimes more than one sentinel lymph node is identified. These nodes are then removed and examined in a laboratory.

If no cancer is found in these nodes, then it is extremely unlikely that the cancer has reached any of your other lymph nodes and you’ll not need any further treatment to your armpit.

If a sentinel lymph node does contain cancer cells, you will be offered further surgery to remove your lymph nodes or radiotherapy to your armpit.

In some hospitals, sentinel lymph node biopsy can sometimes be completed during your breast surgery, so your surgeon may have the option of removing your lymph nodes right away if the test is positive and you will only need one operation. Normally though, the results can take longer and you may have further surgery or radiotherapy after your initial breast surgery.

Axillary node sampling

Axillary node sampling is less common than sentinel lymph node biopsy, which is the preferred procedure.

Axillary node sampling involves removing a small number of the lymph nodes in your lower armpit, usually four or more. The nodes removed are examined in a laboratory.

If no cancer is found in these nodes, it is extremely unlikely that any of your other lymph nodes are affected by cancer and you’ll not need any further treatment to your armpit. If cancer is found in these nodes, you will be offered further surgery to remove your lymph nodes or radiotherapy to your armpit.

How is breast cancer in the lymph nodes treated?

If the tests you have before surgery show that your cancer has spread to your armpit, the affected lymph nodes will be removed during your surgery.

If instead you have lymph node tests during surgery and they show that your cancer has spread to any of your lymph nodes, you will be offered one of two treatments to reduce the risk of the cancer coming back or spreading further:

  • Removal of all the remaining lymph nodes in the armpit with further surgery (called an axillary node clearance)
  • Radiotherapy to the armpit

Research suggests that these treatments are equally effective, but radiotherapy may cause fewer side effects. Your breast care team will discuss the advantages and disadvantages of each type of treatment with you.

The possible short-term side effects of axillary node clearance are:

  • Pain and difficulty moving your arm
  • Collection of fluid in the armpit (seroma)
  • Increased risk of infections

Lymphoedema (swelling of the arm) is a possible long-term side effect.

If you have radiotherapy to the armpit you may experience short-term reddening or burning of the area of skin treated (like strong sunburn) and tiredness. Stiffness in the shoulder and lymphoedema are possible long-term side effects.

Let your breast care team know if you experience any of these side effects, as they should be able to help you manage them.

Need more information?

You can find information on managing lymphoedema at Breast Cancer Care and The Lymphoedema Support Network.

Information Standard

Information last reviewed: November 2017

Next review due: November 2020

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