Sentinel Node Biopsy

This is a new technique that aims to make assessment of the draining lymph-nodes more accurate and to reduce some of the complications associated with axillary lymph-node dissection. It is based on the concept that a cancer probably drains to one particular lymph node first. We can identify and remove this "sentinel node" and the pathologist can tell us whether it contains cancer cells. If no cancer cells are seen then it is very unlikely that any of the other axillary nodes will be affected and they do not need to be removed.

The sentinel node is found by injecting a Blue dye (Patent blue V) around the cancer at the start of the operation. After a few minutes dye moves down the lymphatics to the draining node. A cut is made under the arm and the dye shows up as a thin blue track in the tissue. The first lymph node to turn blue is the sentinel node and will be removed. If it contains cancer cells then a standard axillary lymph-node dissection is required as there may be other positive nodes If not, then no further dissection is necessary.

If a sentinel node cannot be identified with this technique then a standard level 2 axillary dissection will be performed to ensure that affected nodes are not left behind.

Localisation can be performed using a radioactive dye, blue dye or a combination of these tracers.

Further tests will be performed on the sentinel node after surgery. If these more sensitive tests show cancer cells that were not recognised during surgery then it may be necessary to return to theatre for a full axillary node dissection a few days later.

Sentinel node biopsy is not suitable for all situations. It is important that the surgeon has trained in this procedure and has validated his results with the technique

Possible complications:

• The blue dye can cause some staining of the skin and temporary discolouration of the urine.
• There is a very small risk of an allergic reaction to the dye
• Complications of axillary dissection as listed above can all occur but seem to be less common.
• Axillary recurrence of the cancer. This is unusual but the long term risk is still being evaluated for this new procedure.

After breast conserving surgery or simple mastectomy you will spend about three nights in hospital. By the time you go home you will be quite mobile and will not need any special nursing help with dressings or drains. I will see you at the clinic to discuss your results once these are available a few days later.