Am I at risk?

Breast cancer is the most common cancer in the UK. The lifetime risk of developing breast cancer is one in eight by the age of 90 and one risk factor is increasing age; around 81 per cent of all breast cancer occurs in women over the age of 50. The older the woman, the higher the risk.

We still don't know what the exact causes of breast cancer are, or why some people get breast cancer and some don't. Research suggest that breast cancer is caused by a combination of many different things.

Out of all the people diagnosed with breast cancer, only a small number will know why they have developed it – those found to have inherited a fault in a breast cancer gene. For more information on this, see our Breast cancer in families booklet.

We do know that some things can increase or decrease the likelihood of getting breast cancer. These are called 'risk factors'. However, as we are all different, risk factors will not affect us all in the same way. One person may have many risk factors and not develop breast cancer, while another may have very few and be diagnosed with the disease.

It’s important to remember that your individual risk is unique and can change over time – for example, as you get older or if your family history changes (by someone receiving a cancer diagnosis).

What is risk?

Risk measures the chance of something happening. There are a number of ways in which risk is represented. Risk is commonly communicated, by healthcare professionals and the mass media, in two ways – relative risk and absolute risk.

• Relative risk: the likelihood of something happening to people exposed to a particular risk, compared to those not exposed to that risk.
• Absolute risk: the chances of something happening to a person over a period of time.

Risk can be reported in many ways, from single word descriptions to lengthy comparative studies. It is important to remember that risk is not always communicated clearly and it can be difficult to figure out what a risk means to a person in real terms.

What does it mean to me?

We all view risk in different ways. What risk means to us as individuals depends on our background and upbringing. Our culture, where we live and how we live our lives – as well as our personal experience.

So when we hear about a particular risk, we decide what that risk means to us and how important it is in our life right now.

Can I reduce my risk of developing breast cancer?

With the exact causes of breast cancer unknown, we are not able to prevent breast cancer happening. Some women who have one of the BRCA genes may be offered preventative treatment, such as risk-reducing surgery or drug trials, but these treatments do not completely remove the chances of breast cancer.

We know that breast cancer is a complex disease influenced by genetics, lifestyle choices and environmental factors. Many of these factors are out of our control. Some factors can be influenced by a change in lifestyle choices, for example maintaining a healthy weight or not drinking more alcohol than the recommended daily amount, although this may not stop breast cancer developing.

Before you make lifestyle changes, the risk and benefits should be considered clearly, as these changes could affect your quality of life and increase your fear of breast cancer developing.

Main breast cancer risk factors

Gender

Being a woman is the single biggest risk factor for developing breast cancer. Around 50,000 new cases of breast cancer are diagnosed each year, of which more than 300 are men.

Age

After gender, age is the most significant risk factor for developing breast cancer – the older the person, the higher the risk. Most breast cancers (around 81 per cent) occur in women over the age of 50. Most men who get breast cancer are over 60.

The table below gives the estimated risk of developing breast cancer according to age, showing how risk goes up as we get older.

Significant family history

Because breast cancer in the most common cancer in women in the UK, having someone in your family with breast cancer doesn’t always mean your own risk is increased. For most people, having a relative with breast cancer does not increase their risk.

However, a small number of women and men may have an increased risk of developing breast cancer because they have a significant family history. A family history may be significant if there are a number of cases of breast and ovarian cancer in the family, or cases at a young age, or male relatives with breast cancer.

Other breast cancer risk factors

There are other known factors, some of which are listed below, that might slightly increase the risk of developing breast cancer. Factors increasing risk include:

• periods starting before the age of 12
• menopause after the age of 50
• not having children
• first pregnancy at the age of 30 or over
• taking Hormone Replacement Therapy (HRT) – depending on what type you take and how long you take it (the risk reduces over time once you stop)
• taking the oral contraceptive pill for a number of years (the risk reduces over time once you stop)
• being overweight, especially after the menopause
• drinking more alcohol than the recommended daily amount (two units for women, three for men)
• a few types of benign (non-cancerous) breast problems
• exposure to high levels of radiation.

Remember that having one or more factors that increase risk does not mean that you will develop breast cancer. It might mean the likelihood of you developing breast cancer is only slightly greater than if you didn’t have these risk factors and your individual risk may still be small overall.

There are also several factors which may decrease your risk of developing breast cancer. Some of these include:

• periods starting after the age of 12
• menopause before the age of 45
• having children (especially having the first before the age of 20)
• breastfeeding (for a minimum of five months – this could be one baby or more)
• risk-reducing surgery (only for those who have inherited a faulty gene)
• taking regular exercise.