Understanding cancer screening
What is screening?
Cancer screening is meant for healthy people with no symptoms at all. Screening looks for early signs that could indicate cancer is developing. It can help spot cancers at an early stage, when treatment is more likely to be successful and the chances of survival are much better. In some cases, it can even prevent cancers from developing at all, by picking up early changes that can then be treated to stop them turning into cancer. Cervical screening is the best example of this.
If you have noticed an unusual change in your body that doesn’t go away, or you have noticed something that could be a sign of cancer, please see your GP. This is important even if you have recently had screening, or if you will be having screening soon.
What screening programmes are available?
In the UK there are national screening programmes for breast, cervical and bowel cancer. There is no screening programme for prostate cancer because the PSA test is not reliable enough, but men over 50 can have the test if they ask for it.
Breast screening is offered to women aged 50-70 in all UK nations. Women over 70 can still be screened, but will need to make their own appointment as they will not get an invitation. In England, this age range is gradually being extended to 47-73.
Cervical screening is offered to women aged 25-64 in England, Wales and Northern Ireland. In Scotland, women aged 20-60 are offered screening, but this is changing to become the same as the other countries from 2016.
Bowel screening is offered to men and women aged 60-74 in England, Wales and Northern Ireland. In Scotland, men and women aged 50-74 are offered screening. In England, a new test called Bowel Scope is starting to be offered to people at age 55.
You will be invited for screening as long as you are registered with a GP. If you aren’t registered, you can find a local GP on NHS Choices.
If you are older than the age range for breast screening in any UK nation, or for bowel screening in England and Scotland, you can still be screened if you want. But you won’t get an automatic invitation. You can make your own breast screening appointment, or request a bowel screening kit. How to do this depends on your local area, but your GP surgery can tell you who to contact.
What about people with a high family risk of cancer?
Some people may have a higher risk of certain cancers, perhaps because of a strong family history. Their doctors may recommend they have some extra tests that are different to screening for the general population.
What if I’m not eligible for screening?
No matter what age you are, if you notice anything out of the ordinary for you and your body, it’s important to see your doctor to get checked out.
There are also lots of things you can do to reduce your risk of developing cancer in the first place.
Should I be screened?
Whether or not to go for screening is your choice. You will be sent information with your screening invitation about the benefits and risks of the test, so you should read this information to help you make an informed decision.
You can also ask your doctor if you need help to understand or make a decision.
Benefits of screening
We know that cancer screening saves thousands of lives each year.
Screening can detect cancer at an early stage. If cancer is picked up early, it means that treatments are more likely to work and more people survive.
Some screening programmes can also prevent cancer. The cervical screening programme, as well as the new Bowel Scope test, can detect abnormal changes before they can turn into cancer. Treating these early changes can prevent cancer from developing.
Risks of screening
Screening is not perfect, and it can miss cancers. How often this happens varies for different types of screening test. That’s why it is still important to know your body and see your doctor about any unusual changes, even if you have had screening.
Screening can also mean people have to come back for more tests and then find out they don’t have cancer. If this happens, you might feel very anxious.
Sometimes, screening can pick up cancers that would not grow at all, or be very slow growing, and the person may never even know they had it. This is called overdiagnosis. It means that people can get a diagnosis of cancer, and have to go through lots of treatments, that they didn’t really need. But doctors can’t tell which cancers need treating and which don’t, so they offer treatment to everyone diagnosed with cancer. This is a particular problem with breast screening.
Sometimes, the tests themselves can have risks or side effects, like bleeding, pain, or infections.
Know your body
Screening programmes can save lives from cancer. But not all cancers can be screened for, and screening tests are not perfect.
Knowing your body and what’s normal for you can help you to notice any unusual changes that could be signs of cancer. Even if you have been screened for breast, cervical or bowel cancer, if you notice any unusual or persistent changes in your body, it’s is important that you go and see your doctor.
Why isn't screening available for all cancers?
Screening programmes can only be set up for a particular cancer type if it will save lives without too much risk. For the current UK bowel, breast and cervical screening programmes there is evidence that this is the case.
But at the moment, there isn’t enough evidence for screening for any other types of cancer.