What is breast screening?

Breast screening is a way of finding a breast cancer when it is too small to see or feel. It involves having an x-ray of the breast, called a mammogram.

All women registered with a GP and aged 50 to 70 will be invited for breast screening every three years. If you live in England, you may be invited for breast screening between the ages of 47 to 73, as part of a trial. It is rare for women under 50 to develop breast cancer, so they are not routinely screened.

Breast screening cannot prevent breast cancer. It can only find a cancer that is already there. But if a cancer is found, it is often very small and hasn’t spread. This means it is usually easier to treat.

There are some disadvantages of breast screening. Women are sometimes diagnosed and treated for a breast cancer that would not have caused any problems. It can also be uncomfortable and cause worry for some women.

Breast screening

Breast screening is a way of finding breast cancers early, when they are small. When breast cancer is diagnosed early, less treatment is needed and it is more likely to be effective. The first stage of breast screening is a mammogram, which is an x-ray of each breast.

Every year, over two million women have screening with the NHS breast screening programmes in the UK. All women registered with a GP (family doctor) and aged between 50 to 70 are invited for a mammogram every three years.

In England, a research trial is looking at extending the age range to include women aged between 47 to 49 and 71 to 73. Most local breast screening centres in England are taking part. If you live in England, you may be invited to have breast screening as part of this trial.

If you’re under 50

Women younger than the screening age are not routinely offered breast screening. This is because breast cancer is less common in women under the age of 50. Mammograms are also less reliable before the menopause, which happens around the age of 50. After the menopause, breast tissue is less dense. This is because there is less glandular and connective tissue, and more fatty tissue. This makes mammograms easier to read and the results more reliable.

Women under 50 who have an increased risk of breast cancer because of a family history of breast cancer may be offered regular screening.

Remember, you should always see your GP if you have any changes in your breasts.

If you’re over 70

If you are over the age of 70, you can still have screening because you are still at risk of breast cancer. You won’t receive an invitation letter, but you can contact your local screening clinic every three years to arrange a mammogram.

You can find out where your local screening clinic is by asking your GP. Or you can search on the NHS website.

If I hadn’t found out that I could go for a free mammogram, I wouldn’t have known I had breast cancer. I didn’t have lumps or other symptoms.

Sonja

What happens during breast screening?

In this video, made by healthtalk.org, people affected by cancer share their experiences. They may not be the same as yours, or reflect your situation. Talk to your healthcare team if you have any questions. © University of Oxford

About healthtalk.org videos

What happens during breast screening?

In this video, made by healthtalk.org, people affected by cancer share their experiences. They may not be the same as yours, or reflect your situation. Talk to your healthcare team if you have any questions. © University of Oxford

About healthtalk.org videos


Making a decision about breast screening

1 in 8 women will be diagnosed with breast cancer at some time in their life. Breast screening does not prevent breast cancer from developing. But regular breast screening using mammograms is the best way to find early breast cancers. This can lead to more successful treatment. Large research trials show that women who have breast screening reduce their risk of dying from breast cancer by up to 20%, compared to those who do not have breast screening.

But there are some possible disadvantages to breast screening. We explain the main benefits and disadvantages below. This might help you to decide whether to take part in the breast screening programme.


Benefits of breast screening

Breast screening saves lives

Research shows that screening programmes probably prevent around 1,300 women in the UK dying from breast cancer every year.

Most cancers found through breast screening are at an early stage, when there is a good chance of treatment being more successful. More than half of all breast cancers found through screening are very small and have not spread to the lymph nodes. The lymph nodes in the armpit are one of the first places breast cancer may spread to.

If a breast cancer is found early and it is small, breast-conserving surgery is usually possible. This is when a surgeon removes the cancer and some surrounding tissue, instead of removing the whole breast. After breast-conserving surgery, you usually are offered radiotherapy treatment.

Around 7 out of 10 (70%) of women diagnosed through screening have breast-conserving surgery. This compares with just over 5 out of 10 (53%) of women diagnosed without having screening.


Disadvantages of breast screening

Breast screening can’t prevent cancer

It only helps to find a breast cancer if it’s already there.

Having a mammogram is uncomfortable

Many women find having a mammogram uncomfortable or even painful, but usually only for a short time. Some women may feel tender in the area for a few days afterwards. Mild painkillers can help with this. Your doctor or nurse at the breast screening clinic can suggest what to take.

Having a mammogram involves x-rays

All x-rays, including mammograms, involve a small amount of radiation. The amount given during a mammogram is very small. The radiation dose is kept as low as possible while making sure it still gives a good quality image. X-ray machines are also carefully checked to make sure they do not expose people to too much radiation. If you are worried about the risks of radiation, talk to the staff at the screening unit.

Results may cause unnecessary worry

Mammograms can sometimes show that there is an abnormal area in the breast. Further tests may show that this is not cancer. This is called a false-positive result.

About 4 in every 100 (4%) women who have breast screening will have an abnormal result and be asked to go for further tests. These tests may include more mammograms, ultrasounds or removing a small piece of breast tissue (biopsy).

3 out of 4 (75%) of the women asked back for further tests will not have breast cancer.

Waiting for test results can be a difficult time. Some women may still feel anxious, even after the doctor or nurse has told them they do not have breast cancer. You may find it helpful to talk to one of our cancer support specialists on 0808 808 00 00.

Mammograms may need to be repeated

Occasionally you might be asked to have another mammogram. This is because: 

  • the first mammogram has missed part of the breast tissue
  • the x-ray picture is blurred
  • there is a problem with the equipment, but this is rare.

Breast screening sometimes misses a cancer

Mammograms are the best way of finding breast cancer early, but they are not perfect. A breast cancer may be missed because:

  • some cancers are difficult to see or cannot be seen on a mammogram
  • the person reading the mammogram may miss the cancer – to reduce this risk, mammograms are always looked at by two specialists.

Breast screening cannot pick up every cancer. You should always see your GP if you have any changes in your breasts, even if you have recently had a normal mammogram result.

Cancer may develop between screenings

Women having screening can still be diagnosed with breast cancer between their appointments, even if their last mammogram was normal. This is known as an interval cancer. If you notice any changes in the way your breasts look or feel, make an appointment to see your GP straight away.

Screening may find a cancer that would never have needed treatment

Some breast cancers that are diagnosed through breast screening may not grow any bigger. Or they may grow so slowly that they would never have caused a problem during a woman’s life. It is not possible to tell which breast cancers do not need treatment, so all women who are diagnosed will be offered treatment. This means that some women will be given treatment they do not need.

It is unclear exactly how many women are treated for a cancer that might never cause a problem. Current research suggests that:

  • for every woman who is prevented from dying from breast cancer through breast screening, about three women will be offered treatment for a cancer that would not have caused a problem
  • about 1 in 5 (20%) of cancers diagnosed through screening would never have caused a problem.

Back to Breast screening

The breasts

Breasts are made of fat, supportive (connective tissue) and glandular tissue that contains lobes (milk glands).

Being breast aware

Knowing what your breasts normally feel and look like can help you to notice any changes early.