What is a sentinel lymph node biopsy (SLNB) for vulval cancer?

If a vulval cancer is under 4cm in size and only in one place, your doctor may suggest a test called a sentinel lymph node biopsy (SNLB).

The sentinel nodes are the first nodes that lymph fluid drains to from your vulva. This means that if the cancer has spread to nearby nodes, the sentinel nodes are the ones that are most likely to be affected.

An SLNB can tell your doctors more about your situation and help them plan the best treatment for you. It is not a treatment.

If the sentinel nodes do not contain cancer cells, it is unlikely that other lymph nodes are affected. This means you will not need to have surgery to remove them.

If they do contain cancer cells, all your remaining lymph nodes will need to be removed or treated with radiotherapy.

Having an SLNB for vulval cancer

An SNLB is a small operation done under a general anaesthetic.

A few hours before the operation, the surgeon injects a tiny amount of radioactive liquid close to the cancer. The liquid makes the sentinel lymph nodes radioactive.

During the operation, the doctor injects a blue dye into the same area. The dye stains the sentinel lymph nodes blue so the surgeon can see them.

The surgeon uses a probe that detects radioactivity to help them find the sentinel lymph nodes. The sentinel nodes are then removed. They are sent to a laboratory and examined under a microscope to see if they contain cancer cells.

If you are eligible for an SLNB, you may have it as part of a clinical trial. Your doctor or nurse will be able to tell you whether it is suitable for you.

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