OurTNBC - lazy

Key Summary

The term ‘triple negative’ is used to describe a type of breast cancer that does not have any of the three receptors commonly found on breast cancer cells.1

Depending on the stage of its diagnosis, Triple Negative Breast Cancer can be particularly aggressive, and more likely to recur than other subtypes of breast cancer.1

Triple negative breast cancer has a greater chance of developing into an advanced (metastatic) stage and has poorer clinical outcomes as shown by higher relapse rates and lower survival rates.2

Around 2,500 Australians a year are diagnosed with TNBC, which is about 15% of the total breast cancer diagnoses across the country each year.3

What is TNBC?

Triple negative breast cancer is a type of breast cancer that doesn’t have the receptors that are commonly found in breast cancer. These receptors make the cancer sensitive to naturally occuring female hormones: oestrogen (ER) and progesterone (PR). These cancers use hormones to help them grow, known as ER-positive and PR-positive breast cancers.1

Other types of breast cancer have too many copies of the HER2 gene, leading to overproduction of a growth-promoting protein called HER2. These are known as HER2-positive cancers.3

Triple negative breast cancer does not have any of these three receptors on cancer cells. This means a different approach to treatment is required.2

To make it easier to understand, think of cancer cells as a house. The front door of the house might have three kinds of locks, called receptors.

One is for the female hormone, oestrogen

One is for the female hormone, progesterone

One is a protein called human epidermal growth factor (HER2)

If your cancer tests positive for these three locks (or receptors), doctors have a few “keys” (like hormone therapy or other drugs) they can use to help destroy the cancer cells and “get inside.”

However, if you have triple-negative breast cancer, those three protective locks aren’t there. This means doctors have fewer “keys” for treatment. However, chemotherapy may be an effective treatment option.

How common is triple negative breast cancer?

Around 2,500 Australian women are diagnosed with TNBC each year, which is about 15% of the 17,000 breast cancers diagnosed across the country each year.4
Anyone can get triple negative breast cancer, however women with an inherited BRCA mutation have an increased risk of developing TNBC.1
Premenopausal women have a higher rate of TNBC than postmenopausal women. Scientists do not yet understand why this is the case, however research is currently underway in this area.1

For more information and expert advice on living with cancer, read our latest blogs and stay connected to our community. You’re not alone. We are here for you every step of the way.

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Glossary of Key Terms

These are explanations of terms that medical professionals and others may use when discussing your TNBC.

Advanced breast cancer

A commonly used term for secondary, metastatic or stage 4 breast cancer

Adjuvant therapy/treatment

Treatment (e.g. chemotherapy) given after surgery.


Hair loss


The area around the nipple

Axillary dissection/clearance

The removal of some or all of the lymph nodes from the armpit to see if the breast cancer has spread beyond the breast.


Not cancerous


The removal of cells or tissue from the body to see if they are cancer cells


Women with a fault, or mutation, in one of these genes have a higher than normal chance of developing breast or ovarian cancer

Breast conserving surgery

Surgery to remove breast cancer and a small area of healthy tissue around the cancer. Also known as lumpectomy.


Treatment for cancer using drugs

Clinical trials

Studies involving patients to see if a new treatment is better than an existing one

Complementary medicines

Complementary medicines are products that are used in addition to conventional medical treatments (e.g. chemotherapy and hormone therapies). Complementary medicines include vitamin and mineral supplements, such as fish oil capsules or vitamin D tablets, and herbal medicines.

Complementary therapies

Complementary therapies are practices that are used in addition to conventional medical treatments (e.g. chemotherapy and hormone therapies).Some examples of complementary therapies often used by women with breast cancer include massage, yoga, acupuncture and reflexology.

Double mastectomy

Removal of both breasts during breast cancer surgery

Ductal Carcinoma In Situ (DCIS)

Non-invasive breast cancer confined to the ducts of the breast

Early breast cancer

Breast cancer that has not spread beyond the breast or lymph nodes under the arm

Early menopause

Menopause occurring in women under 45 years of age. Early menopause is often a side effect of some common treatments for breast cancer.

Lymph nodes

Glands in the armpit and other parts of the body that filter and drain lymph fluid, trapping bacteria, cancer cells and any other particles that could be harmful to the body


A condition that sometimes develops when lymph nodes have been removed during breast cancer surgery and the lymph fluid no longer drains freely, causing swelling in the arm, hand or breast


Another name for breast conserving surgery


The removal of the whole breast during breast cancer surgery

Metastatic breast cancer

Another term for secondary, advanced, or stage 4 breast cancer

Multidisciplinary Team

Often abbreviated to MDT. A team of health professionals who work together to manage a patient’s treatment and care

Neoadjuvant chemotherapy

Chemotherapy treatment given before breast cancer surgery (sometimes used to reduce the size of the tumour to make it easier for the surgeon to operate)


A type of female hormone

Partial mastectomy

Another term for breast conserving surgery

PBS (Pharmaceutical Benefits Scheme)

A scheme funded by the Australian Government to subsidise the cost of certain drugs for eligible consumers


A type of female hormone


Treatment for cancer using X-rays that target a particular area of the body

Secondary breast cancer

Breast cancer that has spread from the breast to other, more distant parts of the body, most commonly the bones, lungs, liver and sometimes the brain. Also known as advanced, metastatic, or stage 4 breast cancer.

Sentinel node biopsy

identification and removal of the first lymph node to which the breast cancer may have spread for testing by a pathologist


Fluid that collects in or around a scar after surgery

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