A method used to identify the sentinel lymph node, the first draining lymph node nearest a cancer. A radioactive substance that can be taken up by lymph nodes is injected at the site of the breast cancer. Then a doctor tracks the movement of this substance from the location in the breast over to the lymph nodes on a computer screen. Once the lymph nodes on the path from the cancer take up the substance and are identified, they can be removed and examined to see if in fact the cancer cells have moved into the lymph nodes.
Read more about sentinel lymph node dissection.
Audio contributed by: Marisa Weiss, M.D.