Breast cancer

What is breast cancer?

Breast cancer is one of the most common types of cancer. It occurs when cells in the breast grow abnormally, forming a tumour or lump.

Breast cancer is not a single disease. There are many types and subtypes. There are two main types of breast cancer: non-invasive and invasive.



young person with cancer getting specialist treatment from youth cancer services by canteen

Specialist treatment and support for young people diagnosed with breast cancer

Specialist treatment and support for young people with cancer aged 15-25 is provided by the Youth Cancer Services (YCS) based in major hospitals throughout Australia. Canteen also offers events and other support for young people with cancer.

Types of breast cancer

Non-invasive breast cancer

In non-invasive breast cancer, also called carcinoma in situ, the cells look like cancer cells but have not spread to nearby tissues. Non-invasive breast cancer can develop into invasive breast cancer.

The main types of non-invasive breast cancer are:

  • Ductal carcinoma in situ (DCIS): abnormal cells in the breast ducts (a tube in the breast that carries milk from the breast lobules to the nipple – also called milk ducts)
  • Lobular carcinoma in situ (LCIS): abnormal cells in the breast lobules (a gland that makes milk)


Invasive breast cancer

Invasive breast cancer has spread outside the breast ducts or lobules of the breast into surrounding breast tissue.

There are two main types are of invasive breast cancer: invasive ductal carcinoma and invasive lobular carcinoma.

Less common types of invasive breast cancer include: Paget’s disease of the nipple; inflammatory breast cancer; medullary carcinoma, mucinous carcinoma and papillary carcinoma. 

If the cancer spreads (metastasises) beyond the breast to other parts of the body, it is called metastatic breast cancer, or advanced breast cancer.


Subtypes of breast cancer

The subtypes of breast cancer are based on the genes a cancer expresses.

The three main subtypes are:

  • Hormone receptor positive breast cancer
  • HER2 positive breast cancer
  • Triple negative breast cancer



young girl using canteen's robots on an ipad to chat with another person

When cancer’s in your life, Canteen is in your corner.


Cancer affects everyone differently. That’s why Canteen provides a wide range of support services to help you overcome the specific challenges you’re dealing with.

Whether you’re dealing with your parent’s cancera brother or sister’s cancer or your own diagnosis, we have got your back. We also have newer services specifically for parents too.

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young person listening to canteen's cancer unscripted podcast
Every cancer experience is different
Listen to Canteen's Cancer Unscripted Podcast Series where young people talk all things cancer and answer the difficult questions.
More info
Visit the Cancer Council for more information about the causes, symptoms, diagnosis and treatment of breast cancer.