Sunday, 21 October 2018

Should PSA test be standard for anyone over 50?

Photo taken from my film re the PSA testing event in Stroud
The UK’s prostate cancer statistics compare poorly in relation to those of its European neighbours. So what about the role of the PSA test?

What is the PSA test?

"The PSA test is a blood test that can help diagnose prostate problems, including prostate cancer. It is a blood test that measures the amount of prostate specific antigen (PSA) in your blood. PSA is a protein produced by normal cells in the prostate and also by prostate cancer cells. It’s normal to have a small amount of PSA in your blood, and the amount rises as you get older and your prostate gets bigger. A raised PSA level may suggest you have a problem with your prostate, but not necessarily cancer. You can have a PSA test at your GP surgery. You will need to discuss it with your GP first. At some GP surgeries you can discuss the test with a practice nurse, and they can do a test if you decide you want one." Prostate Cancer UK 

Statistics from Cancer Research here
If you are having the test it is important to understand the advantages and disadvantages - but certainly seems important to have the test if you have symptoms and in some cases even if you don’t have symptoms (i). See more at the Prostate Cancer UK website.

As many reading this will know, the PSA test is by no means ideal. Research shows that it can help diagnose people earlier and reduce the risk of death (ii) - but it is important to bear in mind that the raised PSA is only a sign that could mean an enlarged prostate, prostatitis and/or prostate cancer. It is also worth noting that a number of other factors can lead to raised PSA like a urine infection, vigorous exercise, ejaculation, medicines and more. Furthermore to confuse matters, some people with prostate cancer don’t have raised PSA levels. 1 in 7 men with a normal PSA level may have prostate cancer, and 1 in 50 men with a normal PSA may have a fast-growing prostate cancer.

What is the national position regarding PSA testing?


The national Prostate Cancer Risk Management Program run by NHS England gives advice to GPs and others about prostate cancer. The advice is; "The PSA test is available free to any well man aged 50 and over who requests it. GPs should not proactively raise the issue of PSA testing with asymptomatic men’"(iii). However this has led to GPs in Gloucestershire behaving very differently; some testing readily, others not. 

Prostate Cancer UK write: “It isn’t clear that screening with the PSA test would have more benefits than disadvantages. Some studies have found that screening with the PSA test could mean fewer men die from prostate cancer. But it would also mean that: many men would have a biopsy, which could cause side effects, a large number of men would be diagnosed with a slow-growing cancer that wouldn’t have caused any symptoms or shortened their life and a large number of these men would have treatment they didn’t need, which could cause side effects. Other studies have found that screening may not reduce the number of deaths from prostate cancer.”

Certainly my biopsy created additional problems and there are also those who have concerns about biopsy’s and their impact on our health - but that is for another blog.

What is Cotswold Prostate Cancer Support Group’s view (iv)?


They write: “Our charity...strongly supports the use of PSA testing as an easy first indicator of the possible need for follow-up investigation for prostate cancer.” They also actively plan and fund free public PSA test events like the one in Stroud I attended with nearly 500 men over 50. There is also a good video filmed at a similar event to the Stroud event, featuring retired consultant, David Baxter-Smith, who explains the PSA test very well.”  See the ten minute film at: https://youtu.be/o-YJvJ-3hGU

As someone who hadn’t got any symptoms but was picked up as having a high PSA by one of the group's free public PSA test event, I am very sympathetic to this view indeed!

Why does the UK has some of worst rates of prostate cancer in Europe?

The Association of the British Pharmaceutical Industry writes (v): "The UK’s prostate cancer statistics compare poorly in relation to those of its European neighbours. The incidence rate for prostate cancer is 111.1 per 100,000 in the UK, compared to a European average of 105.5 per 100,000. Furthermore, the rate of newly diagnosed cases of prostate cancer in the UK is 3% higher than the European average of 23%. Incidence of prostate cancer is increasing across the whole of Europe…. The mortality rate for prostate cancer in the UK is also higher than the European average. Whilst the mortality rate in the UK is 22.8 per 100,000, it is 18.9 per 100,000 in Europe. The UK has a disproportionately higher share of cancer deaths due to prostate cancer than the EU, with the share of deaths caused by the condition standing at 13% and 9% respectively."

Sadly chances of survival for UK patients to five years after diagnosis are also much lower than in Europe. Whilst over 84% of patients with prostate cancer in Europe will survive for five years, in the UK only 78% will survive with the condition for five years after diagnosis.

One of the reasons for this higher incidence is around the more frequent use of the PSA test in the UK and the earlier detection. However this does not translate into higher five year survival usually associated with early diagnosis. We need more research looking at referral processes and patient access to treatment and care to see what is impacting on rates in the UK. It is quite shocking that one in five men with prostate cancer in the UK stated that they did not understand the treatment options available to them; we urgently need improvements in increasing patient awareness of different treatments options (vi).


Public Health England statistics 2015; see here

Is it about money?

The Association of the British Pharmaceutical Industry writes (v): "The UK’s spending on healthcare overall, as well as on cancer and prostate cancer specifically, fall below the European average...The UK spends €497 million per year on prostate cancer...This is significantly lower than the highest spending countries in Europe such as Germany or the Netherlands, which only have marginally higher incidence rates than the UK. Whilst the Netherlands spends nearly €5 more per capita on prostate cancer than the UK, Germany spends more than double the amount on the condition with €20.40 per capita. Although the UK spends a similar amount per capita on prostate cancer as Finland, this is not reflected in outcomes. Finland’s five year survival rate is higher, suggesting that further improvements can be made to the way in which the UK spends its resources."

Public Health England statistics 2015; see here
Clearly healthcare is provided in different ways and it is not so easy to compare countries. Furthermore other aspects of health like the impact of varying diets seem rarely to be considered in thsi context. However all this makes it sound to me like there is work to be done! If other countries can get better survival rates then I am sure we can too. We clearly need a better test than PSA but at the moment that is what we have got. Is there a better way of using it?

Is it time for a baseline PSA test?


In a talk (vii) at the Cotswold Prostate Cancer Group with Dr Jon Rees (who was surgeon and researcher and more recently a GP), he argued against a national screening with PSA as most of the screening is done to men in their 70s and 80s. He argues instead we should be targeting, with PSA tests, men in their mid-50s and early 60s who have a family history or Afro-Caribean backgrounds. He also suggests we need to pay attention to baseline testing; someone at 49 is very low risk but it is still worth doing a PSA test as you can get a reading without the benign enlargement of the prostate. 

Research in Sweden with the blood from 160,000 men, has shown that if your PSA is above average in your 40s (normal is about 0.7) then your risks of prostate cancer are much greater. Hence Dr Rees argues that it is useful to test so that you can see whether further testing might be wise. In other words the the aim of a baseline PSA test is not to help diagnose prostate cancer, but to help work out your risk of getting prostate cancer in the future. If the test suggests you're at higher risk, you and your doctor can decide to do regular PSA tests. This looks like it might be a good way to spot any changes in your PSA level that might suggest prostate cancer.

PSA; more harm than good?


Finally it is worth mentioning the conclusions of the American Preventive Services Task Force (PSTF) who say that PSA tests for prostate cancer do not offer men any tangible benefit in lifespan or quality of life, and conclude that many more men are injured than helped by PSA tests (viii). Chris Woollams, of CANCERactive writes (ix): "The PSTF research concluded that only one man in a thousand tested would derive any real benefit whereas a staggering 100 will receive false positives. Many of these people will then have biopsies which can cause complications including infection."

It is said prostate cancer is "caused" by oestrogen. Oestrogen turns testosterone into DiHydroTestosterone, or DHT and it is this DHT that is the aggressor. The oestrogen may be human or chemical. It has been suggested (mainly in the US) that measuring this might be a more accurate measure of the aggression of the cancer (ix).

What next?


It seems to me that exploring the baseline approach further is overdue. Why if Sweden have found such useful results do we not explore this further? We also urgently need to find a better way of testing for prostate cancer. One of the suggestions at a recent Cotswold Prostate Cancer Support Group meeting was to see if the Gloucestershire Cancer Patient Reference Group might be a way of tackling this issue locally. Certainly the issue is fraught with challenges but it is surely time that we do better. I would hugely welcome any information that might help clarify or correct issues I’ve raised here; either comment or contact me direct.

See also my blog post on biopsies here.


Notes

(ii) Schroder FH, Hugosson J, Roobol MJ, et al. Screening and prostate cancer mortality: results of the European Randomised Study of Screening for Prostate Cancer (ERSPC) at 13 years of follow-up. Lancet 2014;384(9959):2027-35.




(vi) Quality Health, 2015 National cancer Patient Experience Survey, 2016, available at: https://www.quality-health.co.uk/surveys/national-cancer-patient-experience-survey , accessed February 2017.

(vii) See Dr Jon Rees talking: https://youtu.be/7c_JcR2H7Ac

(viii) http://www.junkscience.co.uk/2012/06/junk-science-number-18-the-psa-test-for-prostate-cancer/ 

(ix) https://www.canceractive.com/cancer-active-page-link.aspx?n=171&Title=Prostate

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