What is triple negative breast cancer?

Triple negative breast cancer is a less common type of breast cancer. It develops in about 1 in 5 women with breast cancer (15 to 20%). It is more common in women under 40. It also seems to be more common in black women.

We need further research to understand this more. But triple negative breast cancer can develop in women of any age and ethnicity.

Breast cancer cells may have receptors (proteins) that hormones or a protein called HER2 can attach to. A specialist breast cancer doctor takes a sample of cancer cells during a biopsy or surgery to test for these receptors. If these receptors are found, you are usually treated with hormonal or targeted therapies.

Triple negative breast cancer does not have receptors for hormones, or HER2. This means treatment with hormonal or targeted therapy will not work.

Chemotherapy, along with surgery and radiotherapy, is the most effective treatment for triple negative breast cancer.

Triple negative breast cancer (TNBC) is sometimes described as a faster growing type of breast cancer. This may make you feel worried about it coming back. But the risk of triple negative breast cancer coming back depends on the same factors as any other type of breast cancer.

Basal cell breast cancer

Basal cell breast cancer is a type of breast cancer with a clear pattern of changes in proteins in the cells.

Cancer doctors recognise basal cell breast cancer when they examine the cancer cells under a microscope. It is often linked with triple negative breast cancer.

Basal cell breast cancers are usually triple negative. And most triple negative breast cancers are basal cell cancers. They are similar types of breast cancer, but not exactly the same.

Symptoms of triple negative breast cancer

The symptoms of triple negative breast cancer are the same as for other breast cancer types.

Causes of triple negative breast cancer

The risk factors for triple negative breast cancer are not clear. Some breast cancers depend on hormones to grow. These can be linked with risk factors to do with hormones and having children. But triple negative breast cancer does not seem to share these risk factors.

Most women with triple negative breast cancer have no strong history of breast cancer in their family (hereditary breast cancer). But some women with triple negative breast cancer have an altered BRCA1 gene . This will have been inherited from a parent.

An altered BRCA 1 gene can cause breast cancer to run in families. Most breast cancers caused by BRCA1 are triple negative.

If you have triple negative breast cancer, you may be offered genetic testing. This is even if you do not have a family history of breast cancer. Your cancer doctor or breast care nurse can explain more about this to you.

Diagnosis of triple negative breast cancer

The tests for triple negative breast cancer are the same as for any type of breast cancer. You usually have a:

  • Mammogram

    A mammogram is an x-ray of the breast.

  • Ultrasound scan

    An ultrasound scan uses sound waves to produce a picture of the breast tissue and the lymph nodes (glands) in the armpit.

  • Breast biopsy

    When you have a breast biopsy, your cancer doctor or breast care nurse takes small samples of cells or tissue from your breast. The samples are looked at under a microscope to check for cancer cells. They also do other tests to find out if the cells have receptors (proteins) for hormones, or for HER2.

Staging and grading of triple negative breast cancer

The staging and grading of triple negative breast cancer is the same as for other types of breast cancer.

  • Stage
    The stage of a cancer describes its size, and how far it has spread. Knowing this helps your cancer doctor plan the best treatment for you.
  • Grade
    The grade of breast cancer is how the cancer cells look under a microscope. The grade gives an idea of how slowly or quickly the cancer may develop. There are three grades ranging from low grade to high grade. Triple negative can be any grade but is more likely to be high grade.

Treatment for triple negative breast cancer

Your cancer doctor will talk to you about the best treatment for you. This depends on different factors, such as the stage and grade of the cancer.

Treatment for triple negative breast cancer is usually a combination of:

You may be more likely to have chemotherapy as your first treatment before surgery to remove the cancer.

Sometimes you may have other treatments such as targeted therapy or immunotherapy drugs. You will only have these as part of a clinical trial.

Always tell your cancer doctor or breast care nurse about treatment side effects you have. There are usually ways to control them. They will tell you what you can do to help manage side effects.

Surgery

The type of surgery you have depends on different factors, such as the size and position of the cancer. You and your breast surgeon will decide which operation is best for your situation.

You may be asked to choose which operation you want to have:

  • Breast-conserving surgery

    The surgeon removes the cancer and some normal looking tissue around it (a clear margin). This is called a wide local excision (WLE), or sometimes a lumpectomy. You usually have radiotherapy after a WLE, to treat any remaining cancer cells.

  • Mastectomy

    In some cases, the surgeon may advise a mastectomy. This is when the whole breast is removed. This may be because the lump is large in proportion to the rest of the breast tissue. Or it may be because there are several areas of cancer, in different parts of the breast.

Your surgeon will explain more about the type of surgery that is suitable for you. Some women may choose to have a mastectomy instead of a wide local excision.

Breast reconstruction

If you are having a mastectomy, your surgeon may ask if you want a new breast shape made at the same time. This is called immediate breast reconstruction. You can also choose to delay reconstruction until after your treatment finishes.

Breast reconstruction is specialised surgery done by expert surgeons. There are different types of reconstruction available. Your cancer doctor or breast care nurse will talk to you about this.

Surgery to the lymph nodes

The surgeon usually removes some, or all, of the lymph nodes in your armpit. This is to check if there are any cancer cells in them. If they have been affected by cancer, you may need an operation to remove all lymph nodes from your armpit.

Your cancer doctor may think the cancer is unlikely to affect the lymph nodes. If this is the case, you might have a sentinel lymph node biopsy to check the sentinel lymph nodes. If there are no cancer cells in these lymph nodes, they will not need to remove any more.

Chemotherapy

Chemotherapy is an important treatment for triple negative breast cancer. This is because it is often more effective against cells that are faster growing (high grade). But you usually have chemotherapy even if triple negative breast cancer is low grade, or has not spread to the lymph nodes in the armpit.

For breast cancer, you often have chemotherapy after surgery. This is called adjuvant therapy. It is given to reduce the chance of the cancer coming back. But you can also have chemotherapy before surgery (called neo-adjuvant chemotherapy). If you have triple negative breast cancer, you are more likely to have chemotherapy before surgery.

Chemotherapy can cause side effects, but many of them can be well controlled. Side effects usually improve when treatment is over.

Chemotherapy drugs

Triple negative breast cancer usually responds well to chemotherapy. Clinical trials are on-going to try to find out more about the most effective drugs to use.

The chemotherapy drugs used for triple negative breast cancer are the same drugs used to treat early breast cancer. This includes drugs, such as doxorubicin or epirubicin. You usually have these with docetaxel or paclitaxel.

A drug called carboplatin has also been tested in clinical trials in women with triple negative breast cancer. Cancer doctors need more information about who is most likely to benefit from it. Some research shows it may be more helpful in women who have the altered BRCA 1 or 2 gene.

Radiotherapy

Radiotherapy treats cancer using high-energy x-rays to destroy the cancer cells, while doing as little harm as possible to normal cells. You usually have it after surgery and chemotherapy.

If you have had breast-conserving surgery, you will have radiotherapy to the remaining breast tissue. This reduces the risk of the cancer coming back in that area. Some women who have a mastectomy have radiotherapy to the chest.

Radiotherapy to the breast can cause some side effects. These are usually quite mild. Your cancer doctor, breast care nurse or radiographer will talk to you about how to manage these.

Clinical trials

Your cancer doctor may talk to you about having treatment as part of a clinical trial. Clinical trials test new treatments or different combinations of treatment.

In triple negative breast cancer, they may be testing different combinations of chemotherapy drugs. Some trials may be looking at targeted and immunotherapy drugs, or anti-androgen drugs.

Targeted therapy drugs

Clinical trials are testing how helpful targeted therapy drugs are, usually when given with chemotherapy, in treating triple negative breast cancer. Targeted therapy drugs interfere with the way cancer cells signal or interact with each other. This stops them from growing and dividing.

Olaparib (Lynparza®) is a targeted drug that can work in cancer cells that have a change (mutation) in the BRCA gene. A trial which includes women with triple negative breast cancer is trying to find out how well olaparib works with chemotherapy before surgery.

There is also research going on to see how helpful certain immunotherapy drugs are in treating triple negative breast cancer. Immunotherapy drugs work by acting on the immune system to help it destroy cancer cells. These drugs are usually given as a drip into a vein (intravenously).

Anti-androgen drugs

Androgens are hormones made in both men and women. Some triple negative breast cancers have androgen receptors on the surface of the cancer cells (called androgen positive).

Enzalutamide is an anti-androgen drug that has been used in a trial that includes women with triple negative breast cancer.

After triple negative breast cancer treatment

After treatment, you have regular follow-up appointments for a few years. Your cancer doctor or breast care nurse will explain what this involves. You will usually have a mammogram every year.

Your appointments are a good opportunity to talk about any concerns you have. But if you notice new symptoms between appointments, it is important to contact your cancer doctor or breast care nurse.

Some women may have their follow up checks by telephone. You will get information on what to look out for, and when to contact your breast care nurse for advice.

About our information

  • References

    Below is a sample of the sources used in our triple negative breast cancer information. If you would like more information about the sources we use, please contact us at cancerinformationteam@macmillan.org.uk

    National Institute for Health and Care Excellence (NICE). Early and locally advanced breast cancer: diagnosis and management [accessed Jan 2018] 

    Denkert, C. et al  (2017) Molecular alterations in triple-negative breast cancer—the road to new treatment strategies Lancet 2017; 389: 2430–42 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)32454-0/fulltext [accessed Jan 2018]

     

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Dr Russell Burcombe, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.


How we can help

Macmillan Cancer Support Line
The Macmillan Support Line offers confidential support to people living with cancer and their loved ones. If you need to talk, we'll listen.
0808 808 00 00
7 days a week, 8am - 8pm
Email us
Get in touch via this form
Chat online
7 days a week, 8am - 8pm
Online Community
An anonymous network of people affected by triple negative breast cancer which is free to join. Share experiences, ask questions and talk to people who understand.
Help in your area
What's going on near you? Find out about support groups, where to get information and how to get involved with Macmillan where you live.