Sentinel Lymph Node Biopsy



When a woman is diagnosed with breast cancer, one of the first questions she and her doctor want to answer is, “Has the cancer spread?” Advances in procedural techniques have helped to answer this question and improve the physician’s ability to develop a more effective treatment plan for breast cancer. One of these techniques, sentinel lymph node biopsy helps the physician better understand the extent of the cancer, potentially sparing patients from more invasive surgery and/or side effects.

Lymph nodes are small structures located throughout the body that filter out and destroy bacterial and toxic substances. The sentinel lymph node is the first lymph node of the breast. If cancer cells have broken away from the tumor and traveled away from the breast, the sentinel lymph node is more likely than other nodes to contain these cells. By examining the sentinel node, the physician may better determine the status of the entire axilla (underarm area). For example, if the sentinel lymph node is negative for cancer cells, then the remainder of the lymph nodes may also be cancer free.

Sentinel lymph node biopsy is a minimally invasive technique. For the procedure, the tumor site is injected with a radio-isotope, blue dye, or both. The radioisotope or blue dye is traced into the sentinel node. If a radioisotope is used, a gamma detection device helps the surgeon identify the sentinel node. Once the sentinel node is identified, the surgeon removes the node (or sometimes the first few nodes).

The nodes are then examined under a microscope. If no cancer is found in the sentinel node, it may not be necessary to remove additional nodes. If cancer is found, more lymph will be removed to check for additional areas of cancer.

Some studies have indicated that sentinel lymph node biopsy may be an accurate way to detect whether or not the cancer cells have spread outside of the breast. These studies have found that sentinel lymph node biopsies have accuracy rates greater than 96% for predicting the presence or absence of cancer cells in the axillary lymph nodes. Nevertheless, long-term outcome results are not yet available. Discuss with your doctor whether or not this procedure is appropriate for you.

Download the Sentinel Lymph Node Biopsy brochure for more information and frequently asked questions.