Breast cancer (female) - Screening 

Breast screening 

Breast cancer screening

See what happens during a mammogram, and the benefits of mammography and ultrasound explained.

Media last reviewed: 14/11/2013

Next review due: 14/11/2015

NHS cancer screening

There are some types of cancers you can get free routine screening for

The NHS Breast Screening Programme screens around 1.6 million women a year. Women aged 50 to 70, who are registered with a GP, are automatically invited for screening every three years. You will first be invited for screening between your 50th and 53rd birthday.

Women over the age of 70 are still eligible to be screened and can arrange this through their GP or local screening unit. The NHS has extended the breast screening age range in England so that all women aged 47 to 73 will be invited.

Screening takes place at a special clinic or mobile breast screening unit. A mammogram (X-ray of the breast) is taken by a female health professional. The mammogram is then studied to look for any abnormalities. The aim is to detect breast cancer at an early stage, when any changes in the breast would be too small to feel and when there is a good chance of successful treatment and full recovery.

Not all cancers are found during breast screening. Breast cancer can develop between screening appointments. Even if you go to breast screening, it is important to get to know your breasts so you can spot any unusual changes early on and report them to your GP.

What happens at the screening unit?

Screening is carried out by female staff, who take mammograms to detect abnormalities. The breasts are X-rayed one at a time. The breast is placed on the X-ray machine and gently but firmly compressed with a clear plate. Two X-rays are taken of each breast at different angles.

Most women find the compression uncomfortable and occasionally it may be painful. However, the compression is necessary to ensure the mammogram is clear. Any discomfort will be over quickly.

The results of the mammogram will be sent to you and your GP.

The pros and cons of breast screening

Regular screening prevents deaths from breast cancer – it is estimated to save around 1,300 lives a year. Around a third of breast cancers are diagnosed through screening.

Screening can find breast cancer early and the earlier it is found, the better your chance of surviving it. You are less likely to need a mastectomy (breast removal) or chemotherapy if breast cancer is found early.

However, if you already have an advanced stage of breast cancer, screening may not help. Also, cancers may sometimes be found that are treated even though they may not have caused any symptoms or become life-threatening.


There is also a chance that the results of the mammogram may not be accurate. There are two types of misdiagnosis, known as:

  • a false negative result – you receive a normal result, but cancer is present
  • a false positive result – you receive a positive result and go on to have further tests, but there is no cancer

About 1 in 20 women will be called back for further assessment. Being called back does not mean you definitely have cancer. The first mammogram may have been unclear. About one in six women who are called back for further assessment are diagnosed with breast cancer.


Having a mammogram means your breasts are exposed to a small amount of radiation (2 to 5 millisieverts, or mSv).

For comparison, a person in the UK receives a dose of 2.2 mSv every year from natural background radiation. However, the benefits of screening and early detection are thought to outweigh the risk.

Read more information about the risks and benefits of breast screening.

Screening for women at high risk of breast cancer

You may be eligible for breast cancer screening before the age of 50 if you have a higher than average risk of developing breast cancer. You may be considered to be at an increased risk if you have a family history of breast cancer (female or male) or ovarian cancer.

If you are at an increased risk of developing breast cancer, you may have yearly MRI scans or mammograms, depending on your age and your specific level of risk. MRI scans are sometimes used instead of mammograms because they are better at detecting cancer if you have dense breasts.

Genetic screening for breast cancer

If, following an assessment at a specialist clinic, you are felt to be at an increased risk of breast cancer due to your family history, it may be because one of the genes that make breast cancer more likely runs in your family. In these cases, you should be offered genetic counselling before genetic testing.

Genetic counselling is a service that provides information and advice about genetic conditions. It is provided by healthcare professionals specially trained in the science of human genetics (a genetic counsellor or a clinical geneticist).

The counsellor will discuss the risks, benefits and limitations of genetic testing with you. They will also explain how the information found as a result of genetic testing could have implications for both you and your family.

After you have had genetic counselling, a genetic blood test to look for mutated (altered) versions of genes called BRCA1, BRCA2 and TP53 will be offered because having one of these altered genes increases your chances of developing breast cancer.

If possible, a relative who has already had breast cancer will be tested first because this will make it easier to find any genetic faults. If a faulty gene is found, other family members can then be tested to see if they have the same gene.

If a close relative is not available for testing, you should be offered testing yourself if your family history suggests you have at least a 1 in 10 chance of having a faulty gene.

If genetic tests show you have one of these faulty genes, you may be offered regular screening to check for signs of breast cancer and possible treatments to reduce your risk should also be discussed.

See preventing breast cancer for more information about treatments to reduce your risk.

Want to know more?

Page last reviewed: 09/07/2012

Next review due: 09/07/2014


How helpful is this page?

Average rating

Based on 102 ratings

All ratings

Add your rating


The 5 comments posted are personal views. Any information they give has not been checked and may not be accurate.

Ichuveyem said on 30 October 2012

NHS choices and NHS Screening never reveals the full information. Patient leaflets for screening do not provide selective data and generic advice. Real information can only be given with facts and opinion which is qualified by the author.

In reply to User 559420 an independent panel led by University College London's Professor Sir Michael Marmot was tasked with analysing data from screening trials from a number of countries over recent decades. The report was published in The Lancet this month (Oct 2012). It concluded screening reduces breast cancer mortality but that some overdiagnosis occurs. It found that for every life saved, three women were overdiagnosed. In detail, screening saved 1,307 lives every year in the UK, but led to 3,971 women having unnecessary treatment.

The panel reported 'Of the roughly 307,000 women aged 50--52 years who are invited to begin screening every year, just over 1% would have an overdiagnosed cancer in the next 20 years'

Breast cancer screening is a massive industry for the NHS and the private sector. There is a financial motivation to encourage, continue and extend screening. Profit, wages, and reputation gets in the way of some simple facts.

All I can suggest is seek out as much information as you can find from as many sources as you can find and make your own decision. It is your choice.

Report this content as offensive or unsuitable

tiddles20 said on 02 February 2012

Having received an invite for breast screening & reading the booklet I find that the comment the screening is only carried out by female staff to be sexual discrimination for males who are ruled out of this employment opportunity. I don't suppose that if women are found to have a problem they will then refuse further treatment to be carried out by males! Does that mean that only males treat men genitiles?

Report this content as offensive or unsuitable

User559420 said on 28 May 2011

I have read that many women undergo unneccessary treatments due to breast screening. I am trying to find out how many or what percentage compared to the well publicised figures for the number of lives saved. The leaflet I have been sent does not have reference to the downside of screening only a single sentence about the low radiation exposure. Can any help?

Report this content as offensive or unsuitable

Body_Byoot said on 31 October 2010

Why are there so little facts around the numbers. Yes, breast screening can and does save lives. These numbers are always quoted. But why is this not balanced with the number of patients who have to undergo unnecessary callbacks, biopsies, treatments and pain who will not have breast cancer or not die of it? Why does NHS choices once again not fully inform patients of the pros AND cons of screening and encourage choice?

Report this content as offensive or unsuitable

chatsubo said on 25 October 2010

I do not think that the potential risks associated with screening are fully explained in this section (though the article as a whole is very good)

The Nordic Cochrane Centre estimates that for every life saved by screening a further ten women will be treated unnecessarily.

I think it is important that people have the information needed to make an informed decision on screening.

For more information see:

Report this content as offensive or unsuitable