Prostate cancer can develop slowly over many years without any symptoms. Even when symptoms appear, they may be due to other, benign conditions, so screening tests may be used. A blood test for PSA (prostate specific antigen) is often used for this purpose, but it is not specific to prostate cancer and other benign conditions of the prostate may cause raised levels, leading to unnecessary and invasive investigations such as biopsies. Conversely, some men with prostate cancers may not have raised PSA levels in their blood. PSA measurements are most useful when used to monitor progress of treatment in confirmed cases of prostate cancer.

Research is therefore continuing to find improved diagnostic tests for early prostate cancer and, in particular, tests which can be done by GPs. Testing urine for "markers" which are produced by early prostate cancer would be particularly useful. One urine test, which is undergoing preliminary trials in the UK, is reported to be very promising as it seems to be specific to cancer and would provide a speedy result to patients. Trials are expected to continue into 2006 for full evaluation of the test and commercial development. Until then full details will not be released.

Tests which are performed in the community away from the laboratory can be a great benefit to patients and their carers because results are available immediately, allowing decisions about treatment to be made without delay. They do have some disadvantages however, such as high cost and the need to manage analytical quality very carefully so that the laboratory's standards of accuracy are matched as closely as possible.