Breast cancer

Breast cancer

What is breast cancer?

Breast cancer occurs when the cells lining the breast lobules or ducts grow abnormally and out of control. A tumour can form in the ducts or lobules of the breast.

When the cells that look like breast cancer are still confined to the ducts or lobules of the breast, it is called pre-invasive breast cancer.

Most breast cancers are found when they are invasive. This means the cancer has spread outside the ducts or lobules of the breast into surrounding tissue.

Read more about breast cancer.

Breast cancer symptoms.

Signs to look for include:

  • a lump, lumpiness or thickening
  • changes to the nipple, such as a change in shape, crusting, a sore or an ulcer, redness, unusual discharge, or a nipple that turns in (inverted) when it used to stick out
  • changes to the skin of the breast, such as dimpling of the skin, unusual redness or other colour changes
  • an increase or decrease in the size of the breast
  • a change to the shape of the breast
  • swelling or discomfort in the armpit
  • persistent, unusual pain that is not related to your normal monthly menstrual cycle, remains after a period and occurs in one breast only.

Read more about the symptoms of breast cancer.

Breast cancer statistics

  • Breast cancer is the most common cancer in Australian women, representing 28% of all cancers in women.
  • About 14,000 women are diagnosed each year.
  • One in eight women will be diagnosed with breast cancer by the age of 85.
  • Although it can occur at any age, breast cancer is more common in older women.
  • More than two in three (69%) are diagnosed in women aged 40–69. About one in four (25%) are diagnosed in women aged 70 and over.
  • Nearly 80% of women diagnosed had invasive ductal carcinoma (IDC), while about 11% had invasive lobular carcinoma (ILC).
  • About 130 men are diagnosed in Australia each year. This represents less than 1% of all breast cancers.

The aim of this information is to help you understand about breast cancer. We cannot advise you about the best treatment for you. You need to discuss this with your doctors. However, we hope this information will answer some of your questions and help you think about the questions you would like to ask your doctors or other health carers.