What is triple negative breast cancer?

Understanding triple negative breast cancer

There are many different kinds of breast cancer, and the type that you have will impact the cancer treatment you receive. Triple negative breast cancer accounts for 15% of all breast cancer cases and is an invasive breast cancer, which means the cancer has grown out of the area where it developed and has begun to rapidly spread to nearby breast tissue.2

It is classified as triple negative because it does not have the three proteins that are typically found on breast cancer cells: oestrogen, progesterone and HER2 receptors.3 For women younger than 40-years-old or who have the BRCA1 or BRCA2 gene mutation, there is an increased risk of developing triple negative breast cancer.1

Signs and symptoms of triple negative breast cancer

Triple negative breast cancer can be more aggressive and has limited treatment options compared to other types of breast cancer, which is why it is so important to find the cancer at an early stage. As the signs and symptoms of breast cancer are similar across all breast cancer types, regular self-examination should be conducted to assist you in identifying any changes in your body. For more information on breast cancer signs and symptoms, click here.

Does a triple negative breast cancer diagnosis impact the type of treatment I can receive?

As triple negative breast cancer doesn’t have the hormone receptors oestrogen and progesterone or the HER2 protein, this means that hormone treatments and targeted therapies will not effectively treat the cancer.

Treatment for triple negative breast cancer may include surgery (involving the removal of the lump or the entire breast, known as a mastectomy), chemotherapy and/or radiation therapy.

As chemotherapy is generally very effective at treating early stage triple negative breast cancer, you may be treated with chemotherapy before surgery to reduce the size of the tumour, or after to decrease the risk of cancer recurrence.2

There are also a number of emerging treatments such as immunotherapy that may continue to help triple negative breast cancer patients. Results from a Phase III trial, KEYNOTE-522 showed pembrolizumab (Keytruda) in addition with chemotherapy results in better response rates for early triple negative breast cancer. Please talk to your doctor about whether clinical trials may be an option for your cancer.

Is triple negative breast cancer hereditary?

Both men and women have BRCA1 and BRCA2 genes, which help to prevent the development of cancer. In cases where there is a mutation in these genes, people have a higher risk of developing a number of cancers. BRCA1 and BRCA2 mutations are known to increase the risk of triple negative breast cancers. Following diagnosis of triple negative breast cancer in young women, genetic counselling and testing may be considered to identify whether the BRCA1 or BRCA2 mutation has impacted the cancer’s development.

Finding support

Triple negative breast cancer is less common than other breast cancers, which means that it can be harder for women to get the support they need. Icon is here to support young women with triple negative breast cancer to navigate their treatment and find the right support. Talk to your treatment team about what options might suit you, your life and your type of cancer.


For a full list of references, click here.
  1. American Cancer Society. (2019). Triple-negative Breast Cancer. Retrieved on 18 March 2020 from https://www.cancer.org/cancer/breast-cancer/understanding-a-breast-cancer-diagnosis/types-of-breast-cancer/triple-negative.html
  2. Breast Cancer Network Australia. (2020). Triple negative breast cancer. Retrieved on 18 March 2020 from https://www.bcna.org.au/understanding-breast-cancer/what-is-breast-cancer/triple-negative-breast-cancer/
  3. American Cancer Society. (2019). Breast Cancer. Retrieved on 18 March 2020 from https://www.cancer.org/cancer/breast-cancer/if-you-have-breast-cancer.html

The content found on the Icon Cancer Centre website is intended solely for informational purposes and should not be considered as medical advice. It is not a substitute for consulting with a qualified medical professional. Our website is designed to provide information and support to the general public. Please be mindful that we do not dispense medical advice, and for personalised medical guidance, we strongly advise you to consult with a qualified medical professional or doctor.

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