Triple negative breast cancer

Around 15% of people with early breast cancer have the subtype ‘triple negative’.

Triple negative breast cancers don't have any of the 3 common receptors found on breast cancer cells. Instead, these cancers are:

• oestrogen receptor negative (ER-)
• progesterone receptor negative (PR-) and
• HER2 negative (HER2-).

Being diagnosed with triple negative breast cancer (TNBC) can be confronting. Unfortunately triple negative breast cancers tend to be more fast-growing than other types of breast cancer. Early detection is really important for the best result.

It's important to know that chemotherapy is a very effective treatment.

Find out about treatments for triple negative breast cancer.

Researchers are always looking for new treatments to target triple negative breast cancers.

Subtypes of triple negative breast cancer

There are many different subtypes of triple negative breast cancers. These include basal like, metaplastic, and androgen positive. Sometimes there is no subtype.

The treatment sometimes differs based on subtype. For example, patients with androgen positive TNBC may have surgery before chemotherapy, rather than chemotherapy first.

Risk factors

While anyone can get triple negative breast cancer, it is more common in people who:

• have an inherited BRCA gene mutation (particularly BRCA1)
• are under the age of 40
• have not reached menopause.

Having an inherited BRCA mutation

Around 5 to 10% of all people diagnosed with breast cancer have an inherited BRCA1 or BRCA2 gene fault (‘mutation’). A BRCA1 mutation is associated with a higher risk for triple negative breast cancer.

For this reason, you may be offered genetic testing to show if you carry a BRCA gene mutation. If your specialist does not discuss this with you, you can ask if a genetic test would be helpful for you.

Not all breast cancers caused by BRCA mutations are triple negative. And not all triple negative breast cancers are caused by inherited BRCA mutations.

Read about Breast cancer risk in families and Genetic testing.

Being premenopausal

The rate of triple negative breast cancer in premenopausal women is higher than in postmenopausal women.

Scientists do not yet understand why this is the case but they are conducting research in this area.

Read about Breast cancer in young women.

Risk of triple negative breast cancer coming back

The risk of triple negative breast cancer coming back or spreading in the first 5 years is higher than some other types of breast cancer.

The risk depends on factors such as:

• the subtype of triple negative breast cancer
• the stage of the cancer when diagnosed.

After around 5 years, the risk is similar to, and may be lower than, other types of breast cancer.

After around 10 years, triple negative breast cancer is less likely to come back or spread.