Breast cancer

Breast cancer is when abnormal cells in the breast begin to grow and eventually form a growth (tumour) which can spread within and beyond the breast. Anyone can get breast cancer, but it is most common in women. Breast cancer can often be found early on a mammogram, which can save lives and improve treatment outcomes.


Causes and risks for breast cancer

The most important risk factors for breast cancer are:

  • being female
  • increasing age.

There are other factors that may increase your risk.These include personal, family history and genetic pre-disposition and oestrogen exposure.

Personal

  • You have had breast cancer before.
  • A previous breast biopsy has shown you have had abnormal breast cells before. 
  • Dense breast tissue.
  • Drinking alcohol and smoking.
  • Being overweight.
  • Physical inactivity. 

Family history and genetic pre-disposition

You have close family members, for example, mother, sister, aunt, with breast or ovarian cancer.

For more information see the 'Know your own risk' webpage on the Breast Cancer Foundation NZ website. 

Know your own risk — Breast Cancer Foundation NZ (external link)

Oestrogen exposure

There is a link between lifetime exposure to oestrogen and the development of breast cancer. However, the increase in risk is small. 


Symptoms of breast cancer

There may be no warning signs that you have breast cancer. Some signs and symptoms may include: 

  • a new lump in the breast
  • nipple discharge
  • changes in the nipple, such as turning inwards, ulcers, new itch, persisting redness
  • changes in the breast such as shape or size, or changes on the skin of the breast such as skin dimpling, redness
  • pain in the breast that does not go away. 

It is important that you take the time to learn the normal look and feel of your breasts. Knowing what is normal will help to find any breast changes. Get any concerning changes checked by your general practice (GP) or healthcare provider as soon as possible. 


Diagnosing breast cancer

Early diagnosis of breast cancer while it is still small gives you the best chance of better treatment outcomes and recovery. Having regular mammograms can help find breast cancer early.

Breast screening (internal link)

If you notice a change in your breasts, or a mammogram picks up something unusual, you may need to have further tests. These could include: 

  • a physical examination of your breasts
  • a diagnostic mammogram
  • an ultrasound scan 
  • an MRI scan 
  • a biopsy — taking a tissue sample to look at under a microscope.

Treating breast cancer

The treatment for breast cancer depends on the type and stage (how far it has spread), your age, general health and preferences. 

Treatment options may include: 

  • breast conserving surgery (a wide local excision to remove the cancer and a rim of normal tissue) or a mastectomy (removal of the breast) 
  • x-rays to destroy the cancer cells (radiation therapy)
  • medicines to stop the growth and spread of cancer (hormone therapy, chemotherapy). 

The Cancer Society and the Breast Cancer Foundation NZ have has more detailed information on breast cancer treatments.

Treatment of breast cancer — Cancer Society (external link)  

Treatment options — Breast Cancer Foundation NZ (external link)


Reducing your risk of breast cancer

There are things you can do to reduce your risk of developing breast cancer.

  • Stop drinking alcohol or cut back on the amount you drink.
  • Keep within a healthy weight range.
  • Do regular physical activity. Regular physical activity also decreases the risk of cancer coming back in those who have already been treated for breast cancer.
  • If you use menopause hormone therapy, discuss your risk with your GP or healthcare provider.
  • Breastfeed if possible.

Have regular breast screening from age 45. If you have an increased risk of breast cancer you may choose to start screening at an earlier age. Check with your GP or other healthcare provider. (internal link)