There is increasing pressure on doctors to test men for the early detection of prostate cancer.
Unlike breast cancer screening, which has been shown to reduce mortality, prostate cancer screening has not yet been evaluated and there are several reasons why it may be less effective.
Many men with prostate cancer never experience any ill effects because some tumours are slow growing and not aggressive.
The most sensitive screening tests for prostate cancer are based on levels of prostate specific antigen (PSA). However, the PSA test and follow up biopsies cannot predict reliably whether a man has a cancer that will progress to cause ill health or death.
There have been no reliable evaluations of the effect of treatments for early prostate cancer on mortality. Active treatments can result in major complications such as incontinence and impotence.
There is no evidence on the number of deaths (if any) which could be averted by screening asymptomatic men. Screening may lead to physical and psychological harm resulting from testing, biopsy and treatment. It is not known whether screening for prostate cancer does more good than harm.