Sentinel lymph node biopsy and lymph node removal

What are lymph nodes?

Lymph nodes are small bean-shaped organs that are part of your immune system. They filter the fluid that travels through them (lymph), removing any dead or abnormal cells and bacteria.

If you have been diagnosed with breast cancer, to help plan appropriate treatment your doctor will need to know if the cancer has spread to the lymph nodes.

Lymph nodes can be removed at the same time as having breast surgery (eg breast lump removal or mastectomy) or in a separate operation. Your surgeon may remove all the lymph nodes from your armpit (axilla). This is known as axillary clearance. Alternatively, your surgeon may decide to remove a few of the lymph nodes to test for cancer. This is known as axillary sampling.

Another alternative is sentinel node biopsy. This is an operation in which in which a blue dye and a radioactive isotope is used to find the first lymph node (the “sentinel” node). Usually blue dye is used alone. The node is removed and examined in the laboratory for cancer (sometimes more than one node is removed).

If cancer cells are found in the lymph nodes, further surgery to remove all the lymph nodes or other treatment such as radiotherapy or chemotherapy may also be necessary.

Your surgeon will explain the benefits and associated risk of having these procedures and discuss which is most suitable for you.

Lymph node removal and biopsy

Lymph nodes are usually removed under general anaesthesia. This means you will be asleep during the procedure and will feel no pain. Depending on the surgical technique used, and the extent of your surgery, you may need to stay in hospital for up to three days.

Once the anaesthetic has taken effect, your surgeon will make a cut in the armpit and remove your lymph nodes. After the lymph nodes have been removed, the cut will be closed with dissolvable stitches. The operation usually lasts 45 minutes.

After surgery, your arm and shoulder will feel sore and stiff you are likely to have some pain, swelling and bruising around the operation site. A physiotherapist will visit you before you go home to discuss a programme of exercises that will help you regain strength and movement in your arm and speed up your recovery.

Sentinel node biopsy

Sentinel node biopsy can easily be done using general or local anaesthesia. If you have a local anaesthetic you will be awake but the area will be numb. Your surgeon and anaesthetist will discuss which type of anaesthesia is most suitable for you.

The procedure may be done in two or three stages depending on whether a radioactive isotope is used.

  • Lymphatic mapping is done in a nuclear medicine department and no anaesthetic is required. Your radiologist will inject a small amount of a radioactive isotope around the cancer site. This chemical will drain into your nearby lymph nodes. Using a scanner or a gamma camera, your radiologist will locate the lymph node area and mark this on your skin. The markings will help your surgeon locate the lymph nodes. You will return to your room and be asked to wait for about one hour.
  • Intradermal blue dye injection is done in the operating theatre under general anaesthesia. Alternatively, if you are having your operation under local anaesthesia, this is done before the local anaesthetic is given. Your surgeon will inject a blue dye into the skin over or near the tumour. The dye will drain into the lymph nodes through the vessels under the skin. The dye will take between 3 to 10 minutes to reach the node(s).
  • Sentinel node biopsy: using the skin markings as guidance, your surgeon will cut through the skin and soft tissues to reach the lymph node area. Your surgeon will follow the blue dye pathway to identify the sentinel lymph node. If you had a radioactive isotope your surgeon will also look for the isotope in the sentinel node using the gamma camera. The affected node or nodes will be removed. The skin cut will be closed using dissolvable stitches. The operation usually lasts 30 minutes and the node(s) will be sent to the laboratory for careful analysis.

As with lymph node removal and biopsy, you are likely to have some pain, swelling and bruising around the operation site.

Lymph node surgery and sentinel node biopsy are generally safe procedures. For most women, the benefits are greater than any disadvantages. However, like all surgery, there are some risks.

The main possible complications of any surgery include an unexpected reaction to the anaesthesia, excessive bleeding during or very soon after the operation, infection, or developing a blood clot in the veins of one of your legs (deep vein thrombosis, DVT).

Removing lymph nodes can cause fluid to build up in your arm, making it swollen and painful. This is called lymphoedema. The chance of this happening is very low if only sentinel nodes are removed and your nurse will give you advice about how to prevent lymphoedema.

Sometimes fluid can accumulate under the arm (known as seroma). This can feel uncomfortable and push your arm away from your side. If this occurs, you may need to have the fluid drained.

In rare cases it is possible to have an allergic reaction to the dye used during sentinel node biopsy. Medicines are available to treat any allergic reaction.

The chance of complications depends on the exact type of operation you are having and other factors such as your general health. Ask your surgeon to explain how any risks apply to you.

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