Sentinel Lymph Node Biopsy

A sentinel lymph node is the first lymph node(s) to which cancer cells are most likely to spread from a primary tumor. A sentinel node biopsy is a surgical procedure performed under a general anesthetic in the operating room, and is done to determine if cancer has spread to the lymph nodes. Research has shown that if cancer has spread, it will show up first in the sentinel lymph node(s). Prior to surgery, in the Department of Nuclear Medicine, you will receive an injection of a radioactive tracer near the tumor site. The tracer is then followed with a scanner or probe during a lymphoscintigram that shows where the tracer is draining. The first (sentinel) lymph node — there may be more than one — to show the tracer is then removed during surgery and tested for cancer. If it is determined that cancer exists, all of the lymph nodes in the area will be removed during another surgery at a later date.

Sentinel node biopsy is a departure from the past when all of the lymph nodes near a tumor site were removed and tested for cancer. Testing the sentinel lymph node first is now the standard of care in many medical centers. The benefit for the patient is a less invasive surgery that also lowers the risk of lymphedema, a painful condition that occurs when excess fluid builds up in tissues and causes swelling, due to the removal of the local lymphatic "drainage" system.