Sentinel Lymph Node Biopsy

A sentinel lymph node is one of the first lymph nodes to which breast cancer cells are most likely to spread from a primary (main) tumor. During a sentinel lymph node biopsy (SLNB), doctors identify, remove, and examine the sentinel lymph nodes for the spread of cancerous cells from the breast. Most patients have between one to five sentinel lymph nodes. The number varies between patients, due to individual anatomy.

During a SLNB, the surgeon finds the sentinel nodes using a blue dye or radioactive substance near the tumor. The surgeon then makes a small incision to remove the node for examination. A pathologist examines the lymph node for the presence of tumor cell.

A negative SLNB result suggests that cancer has not spread to the sentinel lymph node. In this instance the tumor is likely confined to the breast and a lower stage of cancer. A positive SLNB result indicates that cancer is present in a sentinel lymph node and may have also spread to other nearby lymph nodes and distant organs. It is seen in cancer of higher stages. This alerts the physicians that additional testing and procedures may need to be done. This biopsy result helps your doctor determine the pathologic stage of the cancer and develop an appropriate treatment plan.