What is breast cancer?

1. What is breast cancer?
2. How common is breast cancer?
3. At what age does breast cancer occur?
4. Who does breast cancer affect?
5. How does breast cancer start?
6. Why does breast cancer occur?
7. Worried about breast cancer?

1. What is breast cancer?

Breast cancer is the most common cancer in the UK.

It mainly affects women, but in rare cases men can get breast cancer too.

Breast cancer can cause symptoms such as a lump. However, a lump is not the only symptom of breast cancer.

The earlier breast cancer is diagnosed, the easier it is to treat. This means it’s important for women to check their breasts regularly and report any unusual changes to their GP.

Back to top


2. How common is breast cancer?

Around one in eight women are diagnosed with breast cancer in their lifetime.

In the UK each year, about 62,000 people are diagnosed with breast cancer, including around 390 men.

Back to top


3. At what age does breast cancer occur?

Breast cancer occurs mainly in older women.

Most women who are diagnosed with breast cancer are over the age of 50. However, it can occur in younger women too.

Most men who get breast cancer are over 60. 

Breast cancer in teenagers is extremely rare.

Back to top


4. Who does breast cancer affect?

Breast cancer mostly affects women, but it’s possible for men to get breast cancer too.

Although you might not think of men as having breasts, in fact men have some breast tissue, albeit a much smaller amount than women.

Find out more about breast cancer in men.

Back to top


5. How does breast cancer start?

Breast cancer starts when cells in the breast begin to divide and grow in an abnormal way.

Breasts contains lobules, which produce milk for breastfeeding. Tubes called ducts carry milk to the nipple. 

The most common type of breast cancer starts in the ducts. Less commonly, breast cancer can start in the lobules.

Back to top


6. Why does breast cancer occur?

Exactly why some people get breast cancer and others don't is not fully understood.

Research suggests that breast cancer is caused by a combination of lots of different factors.

The main things that increase someone’s risk of breast cancer – like being a woman or being older – are beyond our control.

Most breast cancers happen by chance. Having a relative with breast cancer doesn’t automatically mean your own risk is higher.

A small number of breast cancers happen because someone has inherited an altered version of a gene from one of their parents.

Back to top


7. Worried about breast cancer?

If you have questions about your breasts or breast cancer, you can call our free, confidential Helpline on 0808 800 6000.

Back to top


Last reviewed: June 2018
Next planned review begins 2020

Your feedback