Breast cancer facts

What is breast cancer?

Breast cancer starts when cells in the breast begin to divide and grow in an abnormal way. Breast cancer is not one single disease. There are several types of breast cancer. It can be diagnosed at different stages and can grow at different rates. This means that people can have different treatments, depending on what will work best for them.

Breast cancer is the most common cancer in the UK. Around 55,000 people are diagnosed with breast cancer each year. Of these about 350 are men.

The biggest risk factors for developing breast cancer are getting older, being female and, for a few, having a significant family history of the disease.

Just over 80% of breast cancers occur in women who are over the age of 50. Nearly half of all cases are diagnosed in people in the 50-69 age group.

Earlier detection, increased knowledge and understanding of the biology of breast cancer and better treatments mean that survival rates after a diagnosis of breast cancer are improving. More than 8 out of 10 people survive breast cancer beyond five years. More than three quarters of people survive it beyond 10 years. It’s thought that around 550,000 people are alive in the UK who have had a diagnosis of breast cancer.

Facts about breast cancer

The lifetime risk of developing breast cancer is 1 in 8 in women

This means that 1 in 8 women in the UK will develop breast cancer in their lifetime– it also means that 7 out of 8 women won’t develop breast cancer.

Estimated risk of developing breast cancer according to age

  • Risk up to age 29, 1 in 2,000.
  • Risk up to age 39, 1 in 215.
  • Risk up to age 49, 1 in 50.
  • Risk up to age 59, 1 in 22.
  • Risk up to age 69, 1 in 13.
  • Lifetime risk, 1 in 8.

Both women and men get breast cancer

Although it is much rarer than in women, men can get breast cancer too. Every year about 400 men are diagnosed in the UK.

Older people are more likely to get breast cancer than younger people

After gender (being female), age is the strongest risk factor for developing breast cancer – the older the person, the higher the risk. Around 81% of breast cancers occur in women over the age of 50.

What is breast screening?

Breast screening (mammography) is an x-ray examination of the breasts. It may help detect breast cancer before there are any signs or symptoms. The sooner breast cancer is diagnosed the more effective treatment may be.

Because breast cancer is more common in women who are over the age of 50, women aged 50 to 70 are invited for routine breast screening every three years. Also younger women’s breast tissue can be dense, which makes the mammogram image less clear so normal changes or benign (not cancer) breast conditions can be harder to identify.

The age range for the screening programme is being extended to 47-73 by the end of 2016 in England. Going for breast screening will not prevent breast cancer from developing, but it may find a breast cancer sooner – before it can be felt.

Most cases of breast cancer don’t run in the family

Most cases of breast cancer happen by chance. Only around 5% of breast cancers are caused by inheriting an altered (faulty) gene.

Because breast cancer is the most common cancer in the UK, it is not unusual to have one or two people in an extended family who have had breast cancer. For most people, having a relative with breast cancer does not increase their risk of developing the disease.

If you are worried about whether your family history of breast cancer might mean your own risk is increased, speak to your GP (local doctor). You may like to read our information on family history.

Breast cancer can affect women, regardless of the size of their breasts

Breast cancer can affect women with small breasts, medium breasts, large breasts – any size breasts. Breast size is irrelevant.

Finding a lump in your breast doesn’t mean you have breast cancer

There are several benign (not cancer) conditions that can occur in the breast and may cause a lump. Also many women will experience lumpy breasts just before their period. This is a normal response to changing hormones and often the lump or lumpiness disappears after the period. However, if this doesn’t go away, it’s important to get it checked out by a doctor. Any new lump should always be assessed by a doctor, regardless of your age or whether you are still having periods or not.

Content last reviewed December 2013; next planned review 2015

Last edited:

02 May 2014