When someone has breast cancer, doctors need to check if the cancer has spread to the lymph nodes, which are small, bean-shaped glands that help fight infection. The sentinel lymph node is the first lymph node that cancer is most likely to spread to from the breast.

What Is a Sentinel Lymph Node Biopsy?

A sentinel lymph node biopsy is a procedure to find and remove one or a few of these first lymph nodes, so they can be tested for cancer cells. It helps the doctors know how far the cancer has spread, and what treatment is best for you.

How Is It Done?

• Before surgery, a dye and sometimes a small amount of radioactive substance is injected near the cancer site.

• This travels to the sentinel lymph node.

• During surgery, the surgeon uses a special tool to find the node that picked up the dye or radiation.

• That lymph node is removed and sent to the lab for testing.

Why Is It Important?

• It helps avoid removing too many lymph nodes, which can lead to side effects like swelling in the arm (called lymphedema).

• It provides accurate information about whether the cancer has spread.

Is It Safe?

Yes, it’s generally a safe procedure. As with any surgery, there may be risks like infection, bruising, or temporary discomfort, but serious problems are rare.

What Happens After?

• If the lymph nodes do not contain cancer, no further node surgery may be needed.

• If they do show cancer, more treatment like further surgery, radiation, or chemotherapy might be recommended.