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Let's beat cancer sooner

The potential for blood tests that detect cancer is huge.

But what if a test is, in some ways, too good? What if it finds cancers that if left undetected wouldn’t cause a person any harm? And what if it’s not possible to know for certain which cancers need to be treated, or who could avoid a life-altering diagnosis and potential long-term treatment side effects?

This is the situation right now with prostate cancer.

There’s no UK screening programme for prostate cancer. That’s because the blood test that would be used – called the PSA (or prostate specific antigen) test – isn’t reliable enough.

Men over the age of 50 with no symptoms of prostate cancer can still ask for the test in the UK. But its use is hotly debated around the world.

Now, a new Cancer Research UK-funded study, from scientists at the Universities of Bristol and Oxford, sheds more light on how unreliable the test is. And it confirms that for men without symptoms, the PSA test doesn’t save lives.

What is the PSA test?

Prostate cancer is the most common cancer in men, with 46,690 cases diagnosed each year in the UK.

The PSA blood test is one of the main ways, along with a rectal exam, that doctors can look for signs of prostate cancer.

The test measures the level of PSA in a blood sample. And while it’s normal for men to have some PSA in their blood, a raised level can be a sign of prostate cancer.

But PSA can be raised for lots of other reasons too, meaning a man might get an abnormal result when he doesn’t have cancer.

PSA test prostate cancer screening

Copy this link and share our graphic. Credit: Cancer Research UK

It’s this, combined with the test missing some cancers and finding others that would never cause a man any harm, that makes it unreliable for screening.

What does the new study show?

The CAP trial is the largest to date looking at whether the PSA test can reduce the number of men dying from prostate cancer. It includes over 400,000 men from almost 600 GP practices in the UK. Some practices invited men aged 50 to 69 for a one-off appointment with a nurse where they were offered information about PSA testing and, if they wanted it, the test. The rest operated as normal, and didn’t invite men for the test.

After an average of 10 years, the researchers found that the one-off PSA test led to many more prostate cancers being found. But crucially, the men who had the test were no less likely to die of prostate cancer than the men that hadn’t had it.

This suggests that giving a one-off PSA test to men without symptoms doesn’t save lives from prostate cancer, because it:

  • Picks up cancers that are unlikely to cause a person any harm
  • Misses cancers that are aggressive and probably would benefit from treatment

Professor Richard Martin, who led the study from the University of Bristol, says the results show that giving a one-off PSA test to men without symptoms “risks diagnosing more men with a cancer that would never have caused them any harm”.

“In some cases, this might mean men unnecessarily living with the stigma of having a cancer and the side effects of treatment that was not needed, such as incontinence and erectile dysfunction, for many years, maybe even decades,” he adds.

This backs up a study from 2013 that pooled data from 5 of the largest and most rigorous trials on prostate cancer screening. It too found that the test leads to many men being diagnosed with a cancer that did not need to be found. And that screening for prostate cancer using the PSA test doesn’t reduce the number of men dying from the disease.

PSA prostate cancer screening data

Copy this link and share our graphic. Credit: Cancer Research UK

What’s the problem with finding more prostate cancers?

It seems counter-intuitive to suggest that some cancers would be better off left alone. Especially when early diagnosis can boost treatment success for some cancers. But these overdiagnosed cancers pose a serious problem.

What is overdiagnosis?

Some cancers grow fast and spread quickly, but some grow so slowly that if they went undetected they wouldn’t cause a person any problems. People with these harmless cancers won’t have any symptoms, and they won’t die from the disease.

In other words, it doesn’t matter if the cancer is never found.

When these slow-growing cancers are found they’re said to be overdiagnosed.

Read more: Overdiagnosis – when finding cancer can do more harm than good

Unfortunately, there’s no way of telling apart the cancers that need to be found and treated and the ones that could have been left alone. This means that some patients will receive an unnecessary diagnosis, unnecessary treatment, and the emotional and physical side effects they come with.

Richard Roope, a GP and one of Cancer Research UK’s senior clinical advisors, says this highlights the challenge of diagnosing prostate cancer early.

“Some areas of medicine are very clear cut, others less so,” he says. “PSA testing falls very much into the latter. Prostate cancer comes in many shapes and sizes, ranging from the aggressive to the very slow growing. Unfortunately, no available test will discriminate between these.

“What we know is that giving men without symptoms a PSA test does not change the ultimate outcome if cancer is present, meanwhile any treatment used may produce unpleasant side effects.”

What should you do if you’re worried about prostate cancer?

This study shows that having a PSA test when you don’t have any prostate cancer symptoms comes with some serious risks. If you’re still thinking about having the test, it’s important to get the full picture to help you decide. Our website and your doctor can help.

For those with symptoms, or if you notice anything that’s not normal for you, visit your doctor. In most cases it won’t be cancer, but it’s still best to get it checked.

What next for prostate cancer research?

Over 11,000 men die from prostate cancer in the UK every year. And Professor Martin says it’s here that research must be focussed.

We’re not saying that screening for prostate cancer should be discounted. What we’re saying is PSA testing for prostate cancer is not the answer

– Professor Richard Martin

“Finding a way to detect and successfully treat these cancers, ones that are aggressive and harmful, is what we must continue to strive for.

“We’re not saying that screening for prostate cancer should be discounted. What we’re saying is PSA testing for prostate cancer is not the answer.”

One of the most pressing challenges for researchers is finding a way to distinguish the potentially lethal cancers that need treating from the harmless ones that don’t. This would be an important first step in addressing the problem of overdiagnosis of prostate cancer.

One area that’s showing promise is the use of specialised scans. A type of MRI has shown potential in clinical trials as a way of reducing the number of men who need to go through uncomfortable prostate biopsies. The scans could also help accurately map the size and location of prostate tumours and to identify those cancers that are more likely to be aggressive and need treatment.

Our goal is to save men from harm. This means finding a way to stop men with aggressive prostate cancer dying from their disease by developing better tests and more effective treatments. But as the latest research shows, this also means sparing men with harmless cancers an unnecessary but life-altering diagnosis.

Katie Edmunds is a health information officer at Cancer Research UK


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Kenneth March 15, 2018

I was diagnosed with prostate cancer a couple of years ago at age 48. My PSA test came back suggesting I was okay and could probably leave it for a while. However I went for keyhole surgery to remove prostate and I was later told my situation was much worse than what the PSA test had came back with. Basically if I had listened to the results and left it .. I would now be dead. Also the Gleason scale I was told before operation was also wrong. Again if I had went with this information I would now be dead. Very haunted to this day with the voice of doctor telling me it came down to a matter of a week or mabey two for me to be alive or not. I was so angry and still psychologically troubled. Since the operation I am happy to say my blood test “suggest” I am ok.

FP Graziano March 13, 2018

Never good looking for trouble? But what if. Medical research is the answer that hopefully will solve it.

Mike cole March 13, 2018

Yes there should be a test found to be useful for all men to have this decteced early for longevity of life

Ian March 13, 2018

Very useful, my father died from prostrate cancer at 67, now i’m 64 I am getting concerned, but do not want the rectal examination blood test could be useful in my case ?

Angus mcCuaig March 13, 2018

I would like to get a test done

Graham Turner March 13, 2018

The sooner you start the better I have prostate cancer and the biopsy and the examination I found degrading then you are left to make your decision from three options I am lucky in a way it’s watch and wait every three months for blood test

Brian Merritt March 13, 2018

As a result of receiving this text I am seriously considering cancelling my monthly donation to CRUK. I have prostate cancer which at the moment is held back by hormone therapy injections, I was diagnosed after a PSA test which pointed me to further tests which confirmed the diagnosis. If I had not had the PSA test I would not have been diagnosed in time and would not be alive now. If CRUK are using funds to make this crass research possible then I don’t think I want to be part of it.

David Allanson March 13, 2018

Helpful, glad I was sent the text/link to website.

Nick Goddard March 8, 2018

Since the age of 50 I had regular PSA screening as part of a private healthcare package. In 2010, at the age of 57, my PSA had rocketed, although I had no physical symptoms that worried me. The subsequent biopsy produced a Gleason score of 7, and scans indicated that there were nodes extending beyond the prostate wall. In other words I had a fairly aggressive cancer that was in danger of becoming advanced. My treatment of a robotic radical prostatectomy and radio therapy on the prostate bed a year later has been entirely successful and currently my PSA is undetectable.
The message here is that, having no symptoms, without PSA screening the probability is that my cancer would not have been detected before it was too advanced for the chance of a cure!
You cannot tell me that PSA screening does not have the potential to save lives, or at the very least enable treatments to be started earlier therefore extending their lives.

Paul Ledbury March 8, 2018

1. It would seem that the “other” reasons (on the infographic) for having raised PSA levels can be easily mitigated. Why not give better instructions to men having the test? Some NHS pages do have instructions on what not to do before the test ( but none of these were mentioned to me by my GP, and none of them are included in the NHS/Public Health England leaflet I was given (

2. Why the fixation on a one-off test? If it’s that unreliable as a one-off then wouldn’t it be better to use multiple tests over a period, to determine a trend? Like in Ben Stiller’s case:

Jim Davis March 8, 2018

This report is not only inaccurate but misleading. As chairman of Prostate Cancer Support Organisation (PCaSO) in Dorset which has now offered free PSA testing for men. We have now tested 5,000 men. Of these, 600+ have been referred to their GPs and of those, 200 have either been treated (some with advanced prostate cancer) or have been “put on the radar” through active surveillance. Every man is made aware of the advantages and disadvantages of the test before they make their choice. Those with a low score are also advised that the result is a yardstick to compare with any further PSA tests which we recommend they have. We do not rely on anecdotal stories to support our success as we have received scores of letters from grateful men whose cancers have been identified early enough for a complete cure. The article, through its credulous and selective sorting of the “evidence”, is not only misleading but actually undermines the outcomes that we are trying to achieve. It also makes us question the future credibility of CRUK. Early detection of all forms of cancer is key to successful treatment. Symptoms often appear after cancer has already established itself – a contributing factor, I believe to the 12,000 men who die of it annually.

Katie Edmunds March 7, 2018

Hi David,

Thanks for your comment.
The infographic you mention is based on the data from the 2013 Cochrane Review. This review combined results from five of the biggest and most rigorous studies testing if prostate cancer screening would work. The overall conclusion was that PSA screening for prostate cancer doesn’t save lives. The CAP trial, published yesterday, adds further evidence that PSA screening doesn’t save lives.

You can read more about why there aren’t screening programmes for all cancer types on our website.

Best wishes,
Katie, Cancer Research UK

roger bacon March 7, 2018

This research is not taking into perspective the recent PROMIS and ProtecT trial results where men are now having, in most hospitals, an mpMRI scan BEFORE a biopsy, the scan can show accurately if there is any cancer within the gland, if not the man walks away, if there is it can be targeted at the biopsy stage and given a gleason score. Many men now are put on active surveillance if the cancer is insignificant. The recent National Cancer Audit has shown that over treatment has reduced to 8%. The statement about PSA testing does not save lives is rubbish! The large European trial on PSA testing proved that our cancer death rate would reduce by 25%. Why is it in the USA, where PSA screening used to be happen, they decided to stop screening and now the death rate in the USA has increased year on year after screening stopped.

Alan Davies March 7, 2018

The graphic assumes that ALL of those men diagnosed with prostate cancer will be treated. That is clearly not the case unless watchful waiting is considered to be treatment. Even then, I assume that a few of those diagnosed would prefer not to be involved in a watchful waiting programme even. Watchful waiting certainly doesn’t classify as an invasive treatment. As a prostate cancer survivor I am certainly thankful to know that I no longer carry the uncertainty of not knowing whether I will die with prostate cancer or of it.

David Hutchinson March 6, 2018

Where is the real data on PSA testing? The graphic in the article said ‘If there was a PSA Prostate Cancer Screening Programme…’ It then presented data stating that NO lives would be saved as a result of such a programme. Where’s the data behind that statement? Has such a programme ever been conducted and if so, where is the data? I know several asymptomatic men who have been diagnosed with aggressive malignant prostate cancer following a PSA test result with a high number. I know that is anecdotal, but they are real people. How would they register on the graphic, which without real data behind it, is rather an insult to our intelligence. Prove it to me, and I will accept the argument.