By Fron Jackson-Webb, The Conversation.
Healthy men aged 50 to 69 years who request a prostate cancer check will be offered a blood test every two years if draft guidelines released today by two peak cancer groups are adopted.
The guidelines advise men with a family history of prostate cancer to have their first Prostate Specific Antigen (PSA) blood test at age 45 rather than 50. However, men who are unlikely to live another seven years should not be tested at all.
The joint Prostate Cancer Foundation of Australia and Cancer Council Australia draft guidelines were produced in consultation with an advisory panel of clinicians, advocates and researchers.
The guidelines aim to end the confusion about how GPs should respond to requests for prostate cancer tests.
But Monash University Adjunct Clinical Associate Professor Ian Haines said the recommendations were not supported by the evidence and went against American and Canadian guidelines, which recommended against PSA testing.
Every year, around 20% of Australian men aged between 45 and 74 have a PSA test. Around 22,000 men are diagnosed with prostate cancer annually and close to 120,000 men live with the disease.
“A lot of men in Australia are having PSA tests who are never going to benefit from it. Equally, there are a number of men who could benefit but who aren’t being tested,” said Mark Frydenberg, Associate Professor of Surgury at Monash University, who sat on the expert advisory panel.
Rather than annual tests, the guidelines recommend men aged 50 to 69 who do not have symptoms and wish to undergo a PSA test do so every two years.
For men in their 70s, PSA testing would be considered on a case-by-case basis, depending on whether they were likely to live another seven years.
Under the guidelines, GPs would no longer perform rectal prostate examinations. This would only occur in a specialist setting if the patient was referred for specialist care.
The draft guidelines emphasise the importance of GPs providing evidence-based information to patients about the risks and benefits of PSA testing.
“The main benefit is that you … could expect a 25 to 30% reduction in prostate cancer death rates,” said Associate Professor Frydenberg.
The downsides are that the PSA test can have false positives. If further investigation is needed via a biopsy, this carries the some risks of discomfort, bleeding and infection, he said.
“If a cancer is found, they need to have a further discussion about management options,” Professor Frydenberg said.
But Associate Professor Haines said the recommendations overstated the evidence and would cause men to undergo unnecessary procedures that would not save their lives.
“The only screening study that’s positive has, in my opinion, very serious flaws, which have been questioned by the American Cancer Society,” he said.
“Even if you’re diagnosed with cancer, the only study looking at treatment has not shown any benefit.”
Associate Professor Haines said prostate cancer did not behave like other cancers: many remain stable, and many men live and die without ever knowing they had prostate cancer.
But once you receive a cancer diagnosis, your life changes for ever, he said. Men who undergo biopsies run the risk of infection. And those who undergo surgical treatment face many side effects, such as urinary incontinence and erectile dysfunction.
“I think the default position should be that GPs should advise men against screening. A sheet saying this and why, should be provided to all men contemplating screening,” he said.
University of Sydney Professor of Public Health Simon Chapman said while the draft guidelines emphasised doctors communicating the pros and cons to their patients, it was unclear whether this would occur.
“I hear many men talk about how they have been PSA tested without their consent — they have a blood test that their doctors then send for a variety of tests. PSA is often one of these, and many men are not told about this until the result comes back,” he said.
“Studies of men who had been tested should be conducted to determine whether this well-intentioned recommendation will make any difference.
“I would also urge Cancer Councils to fund pseudo-patient studies where men aged 50-69 visit doctors for a check-up and see how many doctors in fact do provide adequate information about both the pros and cons of testing.”
Bond University Professor of Medicine Paul Glasziou, who was on the advisory panel, said he hoped the guidelines would encourage GPs who have not been adequately informing patients of the risks and benefits of PSA testing to start doing so.
“If someone wants to be tested, [the guidelines explain]how you can go about the processes in a rational and evidence-based way to minimise harms.”