Wednesday 18 March
The scientific community has not resolved the debate over the value of prostate cancer screening despite studying more than 230,000 men, a leading prostate cancer researcher at The Institute of Cancer Research (ICR) in London says.
A major international trial has today concluded that prostate cancer screening using the Prostate Specific Antigen (PSA) test reduces the risk of death from prostate cancer by 20 per cent. The results of the European Randomized Study of Screening for Prostate Cancer (ERSPC) are being published online in the New England Journal of Medicine.
But Dr Chris Parker from the ICR and The Everyman Centre says the findings of the study, which examined 162,000 men over 12 years in seven European countries, did not necessarily mean governments should adopt PSA screening as policy.
"PSA screening has always been very controversial in the UK, with opinions sharply divided, but until now the debate was based upon speculation rather than evidence," Dr Parker says.
"Now, for the first time, we have good quality evidence on which to base an opinion, but the controversy is set to continue.
"Proponents of screening will point to the fact that it reduced the risk of death from prostate cancer by 20 per cent.
"Critics will argue that this translates into a benefit for only one in 1,400 men, while around one in 30 men were harmed because they had to deal with the diagnosis and treatment of prostate cancer that would never otherwise have caused any problem."
Prostate cancer is different to other cancers in that while some are aggressive, the majority do not cause any symptoms and men can survive without treatment.
Debate over PSA screening centres on the fact that while it may prolong the lives of a small proportion of men through early detection and treatment, for far more men false-positive results and over-treatment lead to mental and physical harm.
Measuring PSA is the best test available, but it is not very accurate. For example, men with a naturally large prostate can have higher PSA levels then men with a smaller prostate, and infections and inflammation can also cause high levels, resulting in over-diagnosis.
Men whose test results show elevated PSA levels are often referred for a biopsy, which is an invasive procedure that can have complications such as infection.
"Certainly research into a better test for prostate cancer should be a priority, in particular a test which detects the aggressive form of prostate cancer," Dr Parker says.
Dr Parker says the results of a second major trial of PSA screening, which also today published its results online in the New England Journal of Medicine, were less helpful.
The study, which examined 76,000 men in the United States, found no significant difference between men who were allocated to the screening group and those who were not. Screening is much more common in the United States than the United Kingdom.
"The US study suffered from contamination, in that about half of men in the control group chose to undergo screening. This would have reduced the difference in outcomes between the two groups," Dr Parker says.
Media Contact: Science Press Office Jane Bunce, [email protected] or +442071535106
The Institute of Cancer Research
The Institute of Cancer Research is Europe's leading cancer research centre with expert scientists working on cutting edge research. In 2009, The Institute marks its 100 years of world leading research into cancer prevention, diagnosis and treatment. The Institute is a charity that relies on voluntary income. It is one of the world's most cost-effective major cancer research organisations with over 95p in every £ directly supporting research. For more information visit www.icr.ac.uk.
About The Everyman Male Cancer Campaign
Everyman is the UK's leading male cancer campaign which raises awareness of, and funds research into, testicular and prostate cancer. Everyman funds research at The Everyman Centre – Europe’s first and only centre dedicated to male cancer research. Everyman is dedicated to improving the survival rate of men with testicular cancer by raising awareness about the early symptoms. Its scientists have also led groundbreaking research into new treatments for prostate cancer. For more information visit www.everymancancer.org
Notes to Editor
• Prostate cancer has overtaken lung cancer to become the most common cancer in men, affecting almost 35,000 men every year in the UK. One man dies of prostate cancer in the UK every hour.
• ICR researcher Sue Moss is listed as an author on the European study