Sentinel lymph node biopsy

Advocate Health Care uses sentinel lymph node biopsy to determine whether breast cancer has spread to axillary lymph nodes (lymph glands under the arm). Your surgeon finds and removes the sentinel (first) lymph node.

The benefit of this type of biopsy is a lower risk of lymphedema (swelling of the arm). If the sentinel node is cancer-free, research has shown that there is a good possibility that other nodes will also be free of cancer and no further surgery will be necessary.

Axillary lymph node dissection

If the biopsy shows cancer is present, your surgeon will perform an axillary lymph node dissection, which removes lymph nodes from under the arm to be examined by a pathologist for cancer cells. Because each person has different numbers of underarm lymph nodes, the actual number of lymph nodes removed can vary from four to 60.

Axillary reverse mapping

As preparation for both the biopsy and dissection procedures, blue dye is injected in the upper arm of the patient — a technique known as axillary reverse mapping — to help identify the lymphatic channels and lymph nodes that drain the arm. Mapping reduces the risk of lymphedema even more by allowing surgeons to see those channels during the procedure and avoid disrupting them.