Following the discussion in the US triggered by recent reports that the PSA blood test to screen for prostate cancer does not save lives and often leads to unnecessary treatments, European cancer experts say that PSA screening is useful for certain men especially to those who are below 60 years of age, are fit and with a longer life expectancy.
In reaction to the statements made to the US media by the United States Preventive Services Task Force, whose official report is due for release today, European experts said the task force report could have anchored their arguments on `flawed studies.`
“Unfortunately, the evidence now shows that this test does not save men’s lives,” said Dr. Virginia Moyer in the October 6 edition of the New York Times. Moyer, a professor of paediatrics at Baylor College of Medicine and chairwoman of the task force, added: “This test cannot tell the difference between cancers that will and will not affect a man during his natural lifetime. We need to find one that does.”
In the same article Moyer cited several North American and European studies, including the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO), and pointed out that the benefits from PSA screening are not only minimal but can also lead to overtreatment.
Prof. Michael Marberger, urology professor at the Medical University of Vienna’s Department of Urology and board member of the European Association of Urology (EAU) said withholding the option for PSA testing for certain groups of men is misguided.
“The studies from Quebec and Norrkööping and the PLCO study were flawed as screening studies in methodology and cannot be used for this argument,” said Marberger.
“The European Randomized Study of Screening for Prostate Cancer (ERSPC) study clearly showed a survival benefit of PSA screening at a mean follow-up of nine years, but at the price of 1,448 patients having to be screened and 48 to be treated to save one life,” added Marberger.
Moreover, Marberger said the Gothenberg arm of the ERSPC study now has a mean follow-up of 14 years. “The figures have changed to 293 men having to be screened and 12 men having to be treated to save one life. This amounts to a reduction in prostate cancer mortality of 46%,” he noted.
In the meantime, according to Marberger, the PLCO has also done a post hoc analysis and in men without co-morbidity, researchers have documented a reduction of cancer specific mortality of 44 % with 10-year follow-up.
“Clearly mortality is reduced by PSA screening, but it has to be done in younger and fit patients who have a life expectancy for whom this slow growing cancer can really be a threat,” said Marberger.
He pointed out that the Gothenberg group of the ERSPC also analysed the `burden of treatment,` and has showed that for one life saved four men loose erectile function and less than one becomes incontinent.
“These are clear arguments against the statement in the article,” Marberger said as he noted that Eric Klein, a urologist quoted in the New York Times report, also reiterated the benefits of PSA testing for certain groups of patients.
“PSA testing is valuable, it just should be used in a risk adapted manner and ‘overtreatment’ should be avoided by risk adapted treatment (or active surveillance),” Marberger explained.