One of the most important prognositc factors in breast cancer involves accurate staging of the lymph nodes. Lymph nodes are small round organs that are part of the body's lymphatic system. They are found widely throughout the body and are connected to one another by lymph vessels. Breast cancer cells have the ability to travel through the lymph vessels to other parts of your body. A sentinel lymph node is the term given to the first lymph node to which cancer cells are most likely to spread from a primary tumor. Sometimes, there can be more than one sentinel lymph node.
A sentinel lymph node biopsy (SLNB) is a procedure in which the sentinel lymph node is identified, removed, and examined to determine whether cancer cells are present.
• A negative SLNB result suggests that cancer has not developed the ability to spread to nearby lymph nodes or other organs.
• A positive SLNB result indicates that cancer is present in the sentinel lymph node and may be present in other nearby lymph nodes and, possibly, other organs.
The SLNB is performed in the operating room. Blue dye is injected into the breast which travels through the lymphatic system and stains the sentinel lymph nodes blue. The surgeon then finds the sentinel node that is stained with the blue dye and removes the node. The sentinel node is then checked for the presence of cancer cells by a pathologist. If cancer is found, the surgeon may remove additional lymph nodes, either during the same biopsy procedure or during a follow-up surgical procedure.
SLNB is usually done at the same time the primary tumor is removed. However, the procedure can also be done either before or after removal of the tumor