Skip to main content

Welcome to the Circle Health Group website. We've changed our name from BMI Healthcare. Just as before, we have thousands of specialists offering expert healthcare. Click here to find a specialist or a hospital near you.

Breast surgery - sentinel lymph node biopsy

A sentinel lymph node biopsy is a procedure in which the sentinel lymph node is identified, removed, and examined to determine whether cancer cells are present.


What is a Sentinel Lymph Node Biopsy for breast surgery?

The sentinel lymph node is the first lymph node that lymph fluid drains to from the breast, and therefore the lymph node to which cancer cells are most likely to spread from the primary tumour. Sometimes there is more than one sentinel node. The Sentinel Lymph Node Biopsy (SLNB) is a procedure carried out to identify the sentinel lymph node(s) in the breast, so that they can be removed and examined to determine whether cancer cells have spread to them from the main tumour.

How does the SLNB procedure work?

A patient undergoing a Sentinel Lymph Node Biopsy will be injected with a very small dose of radioactive substance and a blue dye near to the nipple; these then enter into the lymphatic channels that subsequently drain into the local lymph nodes. The surgeon will then make a small cut in the armpit and identify the sentinel lymph nodes using a scanning device that detects radioactivity, and remove any lymph nodes that show traces of radioactivity or blue staining from the dye. These lymph nodes are then examined by a pathologist under the microscope for the presence of cancer cells. If cancer cells are found to be present then the surgeon may need to remove further lymph nodes, usually as a follow-up surgical procedure.

What are the benefits of SLNB?

SLNB is beneficial to patient for a number of reasons; in addition to helping doctors 'stage' cancers by identifying which cancers have spread to the lymph nodes, it is also fundamental in avoiding more extensive lymph node surgery. All lymph node surgery can lead to problems with lymph fluid drainage, causing swelling or lymphoedema, and the risk is reduced when fewer lymph nodes are removed.

Are there any risks to SLNB?

As SLNB involve less extensive surgery and removal of fewer lymph nodes than standard lymph node surgery, there is a lower potential for adverse effects or harm. Similar to other surgical procedures, SLNB can cause short-term pain, swelling and bruising at the surgical site; there is a small risk of infection in the wound. Rarely patients can have an allergic reaction to the blue dye used in SLNB. All risks will be discussed in full with patients by the treating consultant prior to the procedure.

For further information or to book a consultation or treatment, please get in touch with our cancer enquiries team: Call us on 0800 157 7747

Content reviewed: October 2014

Specialists offering Breast surgery - sentinel lymph node biopsy

View all specialists

Mr Mohamed Rubnawaz Hanief

Consultant Oncoplastic Breast and Reconstructive Surgeon

MBBS FRCS (Eng.) MSC (Hons) FRCS (Gen)

The Princess Margaret Hospital

View profile Book online

Mrs Fiona Tsang-Wright

Consultant Breast and Reconstructive Surgeon

MBBS, BSc, FRCS England (General Surgery)

The Chiltern Hospital 1 more The Shelburne Hospital

View profile Book online

Mrs Rachel Holt

Consultant Plastic, Reconstructive and Aesthetic Surgeon

MB, ChB, MD, FRCS(plast), DipOBPS

The Alexandra Hospital

View profile Book online

Mr Douglas Macmillan

Consultant Oncoplastic Breast Surgeon


The Park Hospital 1 more The Lincoln Hospital

View profile Book online

Ms Anushka Chaudhry

Consultant Breast and Oncoplastic Surgeon

MBBS, FRCS (Gen Surg)

The Ridgeway Hospital

View profile Book online

Ms Sunita Shrotria

Consultant Breast Surgeon


The Princess Margaret Hospital 1 more The Runnymede Hospital

View profile Book online

Find a specialist