Countless Irish men may have needlessly undergone invasive surgery and chemotherapy because a widely-used blood test erroneously said they had life-threatening prostate cancer.
The controversial finding has been made by the US Preventative Services Task Force, which said the use of the prostate-specific antigen blood test is effectively misdiagnosing patients.
A major study by the independent expert group said the concern is caused by the inability of the test to differentiate between possible prostate cancer which may never pose a risk and its more aggressive, potentially life-threatening form.
This is because the test — which examines protein produced by the prostate gland — can detect a developing malignancy but cannot tell the difference between dangerous levels and those which, while positive, are highly unlikely to be a health risk.
As a result, the US expert group said it is inevitable some patients who did not need treatments such as surgery or chemotherapy were prescribed them — including the estimated 2,500 new Irish cases every year.
The test is used extensively in North America and Europe, including Ireland.
However, despite concern over the implications of the US findings, there is no alternative to screening test.
Responding to the US research, published in the latest edition of peer review journal Annals of Internal Medicine, the Irish Cancer Society’s head of services, Mairéad Lyons, said that the new findings should be of concern for both doctors and patients.
“It is part of a suite of tests available in Ireland, but the prostate-specific antigen test is the screening tool. No one who has a diagnosis of prostate cancer has not undergone a PSA test,” she told the Irish Examiner.
“It’s use is not national policy in Ireland, and we support that, but it is used regularly.
“There is a real need for more research that will help us differentiate the type of cancer a person has.
“But in the meantime, we are asking all doctors to follow the National Cancer Control Platform guidelines, which make it very clear what type of referral pathway should be used,” she added.
An estimated 2,500 Irish men, the vast majority of whom are over the age of 50, are diagnosed with prostate cancer every year.
Of these, an average of 500 will die every 12 months, while one in nine men develop the condition in their lifetime.
Since the late 1990s there has been a five-fold increase in the use of the PSA test in Ireland, which while considered to show questionable results is the best form of screening currently available to potential sufferers.
The Irish Cancer Society has urged anyone who may be showing signs of prostate cancer, such as difficulty passing water, to contact the group or any of its rapid-access screening centres.
They include those in Cork, Limerick, Waterford, Galway and four in Dublin — St Vincent’s, the Mater, St James’s and Beaumont.
* www.cancer.ie; freephone: 1800 200 700.
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