Sentinel Node Biopsy
If the breast cancer is invasive and there is no clinical evidence of tumor within the lymph nodes a sentinel lymph node dissection will be performed. The sentinel lymph node is the main lymph node that drains the breast. Before planned lumpectomy or mastectomy a substance is injected into the breast which then travels through the lymphatic system to the main draining lymph node. The substance is identified in the operating room and the surgeon is able to remove this lymph node through a small incision.
If metastatic spread to the lymph nodes in the armpit is clinically evident prior to surgery, many lymph nodes will be removed.