Sentinel Node Biopsy
What is a sentinel lymph node biopsy?
- This procedure is where the sentinel lymph node is located, removed and tested to detect if cancer cells are present.
- Lymph nodes are part of the body’s immune system which fight infection and filter cancer cells from the body.
- The theory is that cancer can spread from one part of the body to another through lymph nodes and the sentinel is the hypothetical first lymph node draining a cancer.
- Breast cancer cells are most likely to spread to lymph nodes in the armpit or axilla next to the affected breast.
- A positive SLNB indicates the presence of cancer which may have spread to other nodes and possibly, other organs.
- It is important information for a doctor to help determine work out the extent of the disease in the body and to formulate an appropriate treatment plan.
- A SLNB is usually done in the same surgery to remove the primary tumour.
What happens during a sentinel lymph node biopsy?
- Patients require two procedures to isolate the sentinel lymph nodes.
- The first is a nuclear medicine scan usually performed on the day of the operation.
- While under general anaesthetic, a radioactive substance and/or a blue dye is injected into the patient, near the tumour, to identify the position of the sentinel lymph node.
- A device known as a gamma probe is then used to detect radioactivity or search for lymph nodes that are stained with blue dye.
- Once located the surgeon makes a small incision and removes the node.
- A pathologist checks for the presence of cancer and, if found, the surgeon may remove additional lymph nodes either during the same biopsy procedure or in a follow up operation.
- The benefit of SLNB is that only a few lymph nodes are removed thereby avoiding or reducing complications that can arise with a more extensive lymph nodes surgery (complete axillary lymph node dissection).