Screening for prostate cancer using the prostate specific antigen (PSA) test for men with no symptoms is controversial: experts are divided, and Australians are not routinely well-informed.
Prostate cancer is a slow-growing cancer. Men are more likely to die with it – and not ever know they had it – than die from it.
Although there is some evidence to suggest PSA testing might improve prostate cancer survival, there is also evidence of over-diagnosis. This is where men are diagnosed and treated for a cancer that would never have harmed them.
Our recently published research shows that after accessing high-quality, evidence-based information about the risks and benefits, men are less likely to want a PSA test.
Why the confusion?
Many countries do not recommend testing for prostate cancer in men without symptoms. While there is no national screening program, Australian health practitioners conduct opportunistic testing for men with no symptoms.
Because PSA is a simple blood test, it is often added to a man’s blood work-up conducted for other reasons such as cholesterol or fasting blood glucose. By adding a PSA request to the pathology form (sometimes without their knowledge), asymptomatic men are being screened for cancer: whether they want to be or not.
Late last year the National Health and Medical Research Council of Australia (NHMRC) released its Information for Health Practitioners report. Most guidelines (including the NHMRC’s) recommend men should be informed of both the potential benefits and harms associated with screening for prostate cancer, but this is far from routine.
Asking the men
To find out more about whether information about the harms and benefits of PSA screening made a difference to men’s health decisions, we used a novel methodology know as citizen – or community – jury.
We randomly allocated 27 volunteer men aged 50 to 70 to either a two-day “community jury” group or to a control group. The control group was given PSA fact sheets available from the Cancer Council Australia and Andrology Australia websites.
The community jury group also received these fact sheets plus two days of expert information, questions and deliberation. On Saturday, three experts gave “evidence”:
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Professor Jim Dickinson, Professor of Family Medicine, University of Calgary, gave information about basic prostate biology and cancer
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Professor Paul Glasziou, general practitioner and expert in evidence-based medicine (and co-author of this article), gave “evidence” about screening for prostate cancer, emphasising the potential harms
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Professor Frank Gardiner, urologist and prostate cancer expert at the University of Queensland, gave “evidence” emphasising the potential benefits.
(You can watch videos of the presentations here and here).
Men in the community jury group were then able to ask the experts questions about the information.
On Sunday, men in the community jury discussed the information with a facilitator, put forward any further questions to the experts, and then deliberated as a group without a facilitator on two “community questions”:
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Should government campaigns be provided on PSA screening and, if so, what information should be included in those campaigns?
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What do you as a group of men think about a government-organised invitation program for testing for prostate cancer?
We also asked the men whether they would personally get screened for prostate cancer using a PSA test.
Information matters
Most men were surprised by the information. The men in the community jury voted unanimously against a government campaign targeting the public about PSA screening and against an organised invitation program. The men agreed that:
We don’t want the government to invite us or our mates to come along and get tested. We don’t want that to happen because we don’t want our mates to worry. We don’t want people to make a fuss, we don’t want our government to waste our money.
Instead, and unprompted, the men recommended a campaign that targeted general practitioners to assist them in providing consistent information about the harms and benefits for PSA screening to their patients.
We asked all men before and after the study whether they intended to be tested for prostate cancer using a PSA test in the future.
Before the study, men in both groups had similar intentions: most intended to be tested.
After the study, more men in the community jury had changed their minds about being screened for prostate cancer (fewer intended to have the test). This stayed the same when asked three months later. As one participant stated:
I was of the opinion when I came in that every man over 60 should be screened as a matter of fact, but now I think I’ve changed my ideas, that it’s a personal decision.
Not all men in the community jury group changed their individual decision to be tested, but all men didn’t want information campaigns or invitation programs for screening. The men were clearly able to differentiate between a public health priority and an individual health decision.
Community juries and health policies
Health screening tests are on the rise. Depending on your age, you may tested for a range of “conditions” for which you have no symptoms, such as osteoporosis or vitamin D deficiency. But while all carry the risk of over-diagnosis, few screening tests offer proven benefits.
To develop appropriate screening policies, and determine where to direct health funds in a cash-strapped fiscal climate, we need to hear from the people impacted by these policies. Community juries offer a platform for governments to hear the voice of people who have been well informed by experts and consider the information according to both individual values and social benefits.
Community juries have already been used in South Australia to inform government policy and are a promising tool to help shape health policy across local, state and national jurisdictions.
Rae Thomas receives funding from NHMRC Program grant: Screening and Test Evaluation Program.
Jenny Doust receives funding from the Bond University Vice Chancellor.
Paul Glasziou receives funding from NHMRC program grant: the Screening & Test Evaluation Program (STEP).