What is prostate cancer and how is it diagnosed in the UK?

As David Cameron receives treatment and backs calls for NHS screening, we look at the disease and its treatmentMore than 100 MPs urge Streeting to approve prostate cancer screeningDavid Cameron has become the latest high-profile figure to back growing calls for the NHS to start screening men, or at least those at highest risk, for prostate cancer after being treated for it himself.He joined Olympic cycling champion Chris Hoy and prostate cancer charities in saying that recent advances in diagnos