Breast cancer symptoms and risk factors

What are the symptoms?

Breast cancer sometimes has no symptoms, so regular checks are important for women aged 40 and over. Breast changes may not mean cancer, but see a doctor if you notice:

• a lump, lumpiness or thickening, especially in just one breast
• a change in the size or shape of the breast or swelling
• a change to the nipple – change in shape, crusting, sores or ulcers, redness, pain, a clear or bloody discharge, or a nipple that turns in (inverted nipple) when it used to stick out
• a change in the skin – dimpling or indentation, a rash or itchiness, scaly appearance, unusual redness or other colour changes
• swelling or discomfort in the armpit or near the collarbone
• ongoing, unusual breast pain not related to your period.

What are the risk factors?

Many factors can increase your risk of breast cancer, but they do not mean that you will develop it. You can also have none of the known risk factors and still get breast cancer. If you are worried, speak to your doctor. For more information, visit Cancer Australia or Peter MacCallum Cancer Centre.

Personal factors

• Being female is the biggest risk factor – 99% of breast cancer cases are diagnosed in women.
• Risk increases with age for both men and women.
• More than 3 in 4 breast cancer cases are in women over the age of 50. Free breast screening is available.
• Dense breast tissue (as seen on a mammogram) increases your risk.
• Breast implants do not increase breast cancer risk, but some implants are linked with a type of cancer called lymphoma. Visit The Therapeutic Goods Administration for more information about breast implants.

Lifestyle factors

• Being overweight or gaining weight after menopause. Losing weight to a healthy range can lower this.
• Drinking alcohol – the more that you drink, the higher your risk. If you choose to drink, the Australian alcohol guidelines suggest you drink no more than 10 standard drinks a week, and no more than 4 standard drinks on any one day.
• Not getting enough exercise or not being physically active.
• Smoking tobacco. 

Family history

• About 5–10% of breast cancers are due to an inherited breast cancer gene such as BRCA1 or BRCA2.
• Most people with breast cancer do not have a strong family history. However, having several close relatives (e.g. mother, sister, aunt) on the same side of the family who have had breast or ovarian cancer may increase your risk.
• Several close relatives on the same side of the family with prostate or pancreatic cancer may increase your risk.

Hormonal factors

• Long-term use of menopausal hormone therapy (MHT) containing both oestrogen and progesterone.
• Taking the oral contraceptive pill (the pill) for a long time may slightly increase the risk.
• You or your mother using diethylstilboestrol (DES) during pregnancy.
• Transgender women taking gender-affirming hormones for more than 5 years.

Medical history

• Having been previously diagnosed with breast cancer, LCIS or DCIS.
• Some non-cancerous conditions of excessive growth of breast cells (atypical ductal hyperplasia or ADH).
• Having radiation therapy to the chest area for Hodgkin lymphoma.
• Males with a rare genetic syndrome called Klinefelter syndrome. Those with this syndrome have 3 sex chromosomes (XXY) instead of the usual 2 (XY).

Reproductive factors 

• Never having given birth to a child.
• Starting your first period (menstruating) before the age of 12.
• Being older than age 30 when you gave birth to your first child.
• Never having breastfed a child.
• Going through menopause after the age of 55.

Does breast cancer run in families?

Most people with breast cancer do not have a strong family history, but a small number may have inherited a gene fault (also called a mutation) that increases their breast cancer risk.

• BRCA1 and BRCA2 – These are the most common gene mutations linked to breast cancer. Women in families with BRCA1 or BRCA2 are at increased risk of breast and ovarian cancers. Men in families with BRCA2 may be at increased risk of breast and prostate cancers.
• Other genes linked to breast cancer – These include ATM, BARD1, CDH1, CHEK2, PALB2, PTEN, RAD51C, RAD51D, and TP53. More gene mutations linked to breast cancer are being found all the time. A genetic test called an extended gene panel test checks for the most common types of genes linked with breast cancer

To find out if you have inherited a gene mutation, talk to your doctor or breast cancer nurse about visiting a family cancer clinic or genetic oncologist. Your specialist may also be able to order genetic tests. In particular, women diagnosed before 40 years, those with triple negative breast cancer diagnosed before 60 years, and men with breast cancer should ask for a referral. Genetic testing is covered by Medicare for some, but not all, people; ask your doctor about this.