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Breast cancer and risk

Breast cancer is the most common cancer in the UK.

1 in 9 women will develop breast cancer at some point in their lifetime
Over 80% of all breast cancer cases in the UK occur in women over the age of 50

Men can also develop breast cancer, but this is much more rare. Around 300 men are diagnosed with breast cancer each year compared to nearly 46,000 women.

Although breast cancer is thought to be caused by a combination of our genes, lifestyle and environment, very little is known about the exact causes. A risk factor for breast cancer is something that may increase or decrease your likelihood of developing the disease. Having one or more risk factors does not necessarily mean you will get breast cancer – it means that chances of you developing the disease are greater or smaller. Risk factors that have been identified so far include age, gender, having a family history of breast cancer, drinking alcohol, and being obese after the menopause.

For more information see the section on risk factors.

Age is the biggest risk factor

The majority of those who develop breast cancer do not have a significant family

history of the disease.

The majority of those who develop breast cancer do not have a significant family history of the disease. For most women, age is the biggest risk factor for developing breast cancer.

80% of breast cancers occur in women aged over 50.
Breast cancer is rare in women under 40 years old.

Family history and risk

About 5% of breast cancer occurs in women with a strong family

history of breast cancer.

Having a family history of breast cancer means that you may be more likely to develop breast cancer and at a younger age, but it does not mean that you will definitely get the disease.

About 5% of breast cancer occurs in women with a strong family history of breast cancer.
That means that about 2,000 women with a strong family history develop breast cancer each year in the UK.
A further 10-15% of breast cancer cases occur in women with a moderate family history of breast cancer.
That means that approximately another 4,000 to 6,000 women with a moderate family history develop breast cancer each year in the UK.

Also within "Family history"