Mass screening of men for prostate cancer has little impact on the toll from the disease and carries a risk of over-treatment, according to a review published by the British Medical Journal (BMJ) on Wednesday.
University of Florida professor Philipp Dahm looked at the outcome of six trials in which populations of men were tested either using a digital rectal examination or a blood test for an antigen linked to prostate cancer, or were untested.
Screening had negligible effect on the death toll from this disease or indeed on overall mortality.
"Our findings suggest that the expected impact in absolute terms would be modest at best," according to the paper.
Prostate cancer is the commonest non-skin cancer among men worldwide and, after lung tumours, is the second biggest cause of death from cancer among men in the United States. Most cases occur among men aged in their sixties.
Many countries have routine screening programmes for men in their middle age, but this policy is controversial.
One of the problems is that the so-called PSA antigen test, now 20 years old, cannot distinguish between low-risk tumours and aggressive lesions that are often fatal.
Antigen levels can also fluctuate according to the individual and may be skewed by prostate inflammation.
As a result, experts looking at systematic screening have squabbled over whether the benefit of detecting men in danger outweighs the potential harm of over-diagnosing and over-treating men who are healthy.
In a separate study published by the BMJ, researchers found that the level of antigen, as found among men at the age of 60, strongly identified those most at risk.
This would curb the need for repetitive PSA testing among those who were least vulnerable, say its authors.
Others who should be closely monitored are young men with a family history of prostate cancer or who have a relatively high level of PSA in their initial test.
Source: AFP European Edition