If you have a diagnosis of breast cancer or melanoma, your surgeon may recommend a sentinel lymph node biopsy. It is important to understand what this is and why it is done.

Through years of research, we know that breast cancer and melanoma usually follow a predictable course. If it isn’t removed before it begins to spread, the cancer typically travels first to a collection of lymph nodes located near the primary tumor. For breast cancer this is usually the lymph nodes under the arm of the affected side. Because of this, the standard treatment of breast cancer used to be a mastectomy and removal of all of the lymph nodes under the arm (a so-called “modified radical mastectomy”). For melanoma the historical treatment was to remove the primary tumor and all of the lymph nodes to which it might metastasize.

We have subsequently found that a less-invasive procedure is just as successful in treating breast cancer and melanoma. Depending on your situation, you may be a candidate for breast-conserving therapy. This means removal of just the cancer (instead of the entire breast) and just a few lymph nodes under the arm (sentinel lymph node biopsy) instead of all the nodes.

What is the benefit of a sentinel lymph node biopsy? During a sentinel lymph node biopsy, only a few nodes are removed and checked for cancer rather than all of the nodes in the area. The nodes removed are the nodes that are most likely to harbor tumor cells if the tumor has already spread. If the nodes that are removed do not show evidence of cancer, the rest of the nodes are not removed. That is important because it reduces the risk of long-term complications associated with removal of all the lymph nodes in a particular area. Only your surgeon can determine if you are a candidate for a sentinel lymph node biopsy.

The Procedure

On the day of your procedure you will go first to the nuclear medicine department where a small amount of a mildly radioactive substance is injected into your breast or around the melanoma site. The radioactive material then travels through you lymph system to the nodes most likely to be involved with tumor spread.

You will then go to the preoperative preparation area where a nurse will review your medical history and an IV will be started. If you haven’t already done so, you will meet with an anesthesiologist at this time.

When the operating room is ready for you, you will be taken in on a stretcher and will meet the operating room nurses who will help take care of you during the procedure. If you didn’t see your surgeon in the preoperative area, you will see him in the operating room prior to the beginning of the procedure.

You will then move onto the operating room table and the anesthesiologist will give you medication to make you fall asleep. Your surgeon will then perform the procedure while you are completely asleep. When the sentinel lymph nodes are removed, a pathologist will examine them for evidence of cancer. If no cancer is found, no more nodes will be removed and the incision will be closed. If cancer is found in the nodes, the remainder of the lymph nodes in the area will be removed and a small drain might be placed. When the surgery is completed, you will be taken to the recovery area where you will slowly wake up and regain complete consciousness. A nurse will give you any medication you need, as well as a light snack. Your surgeon will speak to your friends or family members in the waiting room during this time.

Postoperative Information

Once you are fully awake and your pain is controlled, you will be released to the care of yourself and your family. For more information on postoperative care, please see the link entitled “Same Day Surgery.”