Lymph nodes are tiny nodules situated throughout the body that drain lymph fluid and trap and eliminate bacteria, viruses and cancers cells. For women with breast cancer, the presence or absence of cancer cells in nearby lymph nodes (usually in the armpit) plays an important role in determining the stage of the breast cancer and the necessity for additional treatment. The sentinel node is the first lymph node to receive lymphatic drainage from the breast. Surgeons have discovered that the status of the sentinel lymph node reflects the likely presence or absence of tumor cells in the rest of the axilla. Typically, if the sentinel node is "cancer-free," this indicates that other nodes will be as well. For eligible women, the sentinel node biopsy procedure offers a less invasive option than the standard axillary lymph node dissection which typically involves removing ten or more lymph nodes. By minimizing the number of lymph nodes removed, women will usually experience fewer possible side effects.
Today the majority of women are candidates for a sentinel node biopsy. Women with smaller tumors who have a relatively low risk of lymph node involvement are the best candidates for a sentinel lymph node biopsy. If lymph nodes are already known or suspected to be involved, then a standard axillary dissection, which removes more nodes, will probably be necessary. Talk to your doctor to find out whether or not you are an appropriate candidate for a sentinel node biopsy.
The sentinel biopsy procedure is generally an outpatient procedure, and is very often combined with a lumpectomy, or removal of the primary breast cancer. It takes place in an operating room, under general anesthesia. Your surgeon injects a radioactive tracer and/or blue dye into the area around the tumor and then follows the path each takes from the tumor area to the first lymph node under the arm in order to identify the sentinel node. Your surgeon will then remove all radioactive and/or blue stained lymph nodes and send them to the pathology lab for analysis. If the sentinel node is negative for cancer, it is assumed that all other nodes are as well, and this helps determine future treatment. If the node or nodes are positive for cancer, the surgeon will perform an axillary dissection in order to remove more nodes. This may be performed at the same time as the sentinel node biopsy, or at a later date.
Learn more about the patient-centered, high-quality approach to breast cancer care provided to patients diagnosed and treated at Lahey Hospital & Medical Center.