Sentinel Node Biopsy for Breast Cancer

A better way to check the lymph nodes

Lymph nodes are small glands in the underarms and many other places in the body. If you have breast cancer, your doctor will usually check the underarm lymph nodes.

Most breast cancer is invasive. This means that it can spread. The doctor checks the lymph nodes in the underarm to find out if the cancer has spread and to plan what treatment is needed after surgery.

There are two kinds of surgery to check lymph nodes.

The surgeon can remove many lymph nodes or a few important nodes. The smaller surgery is usually the best choice. Here’s why:

  • Axillary lymph node dissection (ALND): In the past, doctors usually removed 12 to 15 lymph nodes from the armpit. This can cause serious and long-lasting side effects.
  • Sentinel lymph node biopsy (SLNB): This is a simpler, newer surgery. The surgeon removes a few “sentinel” nodes. If there is cancer in the lymph nodes, the sentinel are the first to be involved.
  • If there’s no cancer in the sentinel nodes, it is very unlikely that other underarm nodes have cancer. You can avoid the pain and risks of the bigger surgery.

Usually, SLNB is the better choice.

Doctors usually recommend the smaller surgery if:

  • You have early-stage breast cancer.
  • And your lymph nodes do not feel too large or look suspicious in a physical exam or ultrasound.

Most women do not have cancer in their lymph nodes. The smaller SLNB helps them avoid the pain and risks of the bigger surgery.

Even if a few cancer cells are found, many women can still avoid ALND.

Taking out many nodes (ALND) has more risks.

Risks and side effects of ALND include:

  • A condition called lymphedema. This is much more likely with ALND. It causes pain and swelling in the arm. It can be severe. It can be treated, but not cured.
  • Limited movement in the arm and shoulder (“frozen” shoulder).
  • Numbness of skin on upper arm.
  • A rope-like scar in the underarm area. The scar can limit motion. You may need physical therapy.
  • Increased risk of infection in the arm.

ALND costs more.

For ALND, you often need to stay overnight in the hospital. If you get lymphedema, you may have more costs for doctor visits, physical therapy, and other treatments.

SLNB is done in an outpatient surgery center.

So when is ALND needed?

You might need ALND if:

  • The tumor is more than two inches across.
  • A physical exam finds that the lymph nodes are larger than normal. You might need a needle biopsy first to check if the large nodes.
  • SLNB finds more than a few cancer cells.

This report is for you to use when talking with your healthcare provider. It is not a substitute for medical advice and treatment. Use of this report is at your own risk.

© 2017 Consumer Reports. Developed in cooperation with the American College of Surgeons.