Removing lymph nodes

The axillary lymph nodes, which are in and around the armpit, are where cancer cells from the breast usually spread to first. Removing some or all of these lymph nodes helps your doctor to check for any cancer spread. The operation to remove lymph nodes is called axillary surgery. It is usually done during breast surgery but may be done in a separate operation. There are two main types of axillary surgery.

Learn more about:

• Sentinel lymph node biopsy
• Axillary lymph node dissection
• Side effects
• Finding the sentinel nodes

Sentinel lymph node biopsy (SLNB)

When breast cancer spreads outside the breast, it first goes to particular lymph nodes in the armpit or near the breastbone (sternum). These are called the sentinel nodes. A sentinel node biopsy finds and removes them so they can be tested for cancer cells.

If there are no cancer cells in the sentinel nodes, the rest of the lymph nodes are left in place. If there is more than a small amount of disease in the sentinel nodes, you may have axillary lymph node dissection or radiation therapy.

Axillary lymph node dissection (ALND)

This is also called axillary lymph node clearance (AC). If cancer is found in the lymph nodes, then most or all of the axillary lymph nodes (usually 10–25) will be removed to reduce the risk of the cancer coming back (recurrence) in the armpit. The results also guide what other treatment your doctor recommends.

Side effects

You may have arm or shoulder stiffness, weakness, reduced movement and pain; numbness in the arm, shoulder, armpit and parts of the chest; seroma – which is fluid collecting near the surgical scar; lymphoedema; and cording. Side effects are usually worse after axillary lymph node dissection because more lymph nodes are removed.

Finding the sentinel nodes

To work out which lymph nodes are sentinel nodes, one or a combination of these procedures is used:

	Lymphatic mapping A small amount of a harmless radioactive material is injected into the skin over the breast cancer tumour. A CT scan is then taken to show which lymph nodes the radioactive material flows to first. These are most likely to be the sentinel nodes. Lymphatic mapping is done either on the day of the biopsy, or the day before the biopsy.
	Blue dye injection (not always used) If dye is being used, it will be injected into the breast. The dye moves into the lymphatic vessels and stains the sentinel nodes first. This is done under general anaesthetic during the biopsy. Because of the dye, you may notice blue-green urine (wee) and bowel movements (poo) when you go to the toilet the next day. You may also have a blue patch on the breast for weeks or longer. Your skin may look a bit grey, but will fade once the dye washes out in your urine.
	Handheld probe As well as looking at where the blue dye travels to first (if used), the surgeon uses a small handheld device called a probe during the biopsy to detect the radioactive substance injected during the lymphatic mapping. This helps to check that the sentinel nodes have been located and the surgeon can then remove them for testing.

For more on this, see our general section on Surgery.

→ READ MORE: What to expect after breast surgery

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