Why are both urine and blood samples taken annually?
ERSPC and ProtecT studies have suggested an appropriate PSA level for biopsy in the general population to be 3.0ng/ml with a screening interval of 4 years. (Otto and de Koning, 2004; Postma et al, 2004). It is believed that the population of men which is being targeted by the IMPACT study may have a higher risk of developing prostate cancer (and develop it at an earlier age). We will use a screening interval of one year to establish a pattern of PSA in each individual over a 5 year period and see if this is different between the case and control groups. In addition, blood and urine samples are taken with the aim of investigating potential new markers of prostate cancer, which could be used in addition to the PSA test.
