Sentinel node injection

A sentinel node injection maps the location of your sentinel nodes. These are the first lymph nodes where cancer can spread. 

This test is used for breast cancer patients. When breast cancer cells escape from a breast tumour, they travel to lymph nodes under your arm. The first lymph node they reach is the “sentinel” node. 

We inject a radioactive substance (tracer) into your breast, just under the skin. The tracer travels from the skin through a lymphatic duct to the lymph nodes. A surgeon will take a small piece of tissue (biopsy) or remove the sentinel lymph nodes.

• Tell your doctor about all medicines and natural health products that you use.
• Take the day off work and arrange for someone to bring you home. Anesthesia and pain medicine can make it unsafe to travel alone.
• Follow all instructions about when to stop eating and drinking. You can take prescribed medicines with a sip of water.
• Bring your photo ID and BC Services Card.
• Do not bring your children unless you have someone to care for them during the test.
• Do not wear perfume, cologne or aftershave to your appointment. Some people are allergic to these scents and can have serious reactions.

On the day of your appointment, please arrive 10 minutes early, and check in with the receptionist. 

We will ask you to remove clothing near the injection site. We will give you a gown to wear, if necessary.

A technologist will inject your breast with a radioactive tracer. They will do this with a very small needle. They will inject a small amount of clear liquid just under the skin beside your areola. You may feel a pinch or burning sensation, which will subside within a few minutes. Immediately after your injection, we will take an image of the injection site. We may also take a delayed image 30 minutes to one hour after the injection. 

A surgeon will use a device to track where the radioactive injection has travelled. Your surgeon may also inject a blue dye. During the surgery, they will biopsy or remove your sentinel nodes. A laboratory technician will check these nodes for cancer cells to see if the cancer has spread.

You should receive your test results within several days.

If we find cancer cells in the sentinel node, you may need more surgery to remove more lymph nodes. If we do not, you will not need more surgery. 

If you had the blue dye injection, your urine may turn bright green for a day or two afterward. You might also see a blue mark on your breast. These are normal effects and will go away in a few days.

The Indigenous Wellness Liaison Team is here to support your health journey. Team members offer cultural support and healthcare advocacy. Learn more below or call them at 604-682-2344,62937 or email IWL@providencehealth.bc.ca.

Nuclear Medicine Department

2nd Floor, Providence Wing, St. Paul’s Hospital

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