Prostate Cancer Getting Checked What Tests Might be Done PSA test A small (10ml) sample of your blood will be taken to measure prostate specific antigen (PSA). PSA is produced by both prostate normal and cancer cells. The normal level is up to about 4 micrograms of PSA per litre of blood. PSA is not an accurate diagnostic test. 20% of men diagnosed with prostate cancer have normal levels (0-4) of PSA. Two-thirds of men with raised PSA levels of between 4 and 10 do not have cancer. Above 10, the PSA test is more accurate for diagnosing prostate cancer. The PSA test is a good test to follow-up of men who have already been diagnosed.