Screening for prostate cancer with a blood test can save men’s lives, but the “absolute benefit is small” and many men could face unnecessary treatment and medical complications, according to the most comprehensive study yet. In a review that analysed six trials involving nearly 800,000 men, screening with the prostate-specific antigen (PSA) test reduced prostate cancer deaths by two for every 1,000 men screened, meaning 500 men must be screened to prevent one death from the disease. The benefit became apparent as patients were monitored for longer periods, in particular during the European randomized study of screening for prostate cancer (ERSPC), which followed men for 23 years after screening. “Prostate cancer screening does reduce prostate cancer mortality, although the caveat is that it takes a very extended period of time to realise that benefit,” said Prof Philipp Dahm, a urologist at the University of Minnesota and senior author of the Cochrane review .…