The aim of this multi centre and double-blinded study was to investigate specificities and sensitivities of early detection of prostate cancer with a new protein biomarker, annexin A3, using urine after digital rectal examination/massage (exprimate urine) in direct comparison to the corresponding measurements of the gold standard, total PSA. The material obtained by this non-invasive procedure was moreover used to determine appropriate cut-off values and optimal fractions (e.g. after centrifugation) and calibrations for quantitative measurements of this novel marker.
Patients (500-750) were (and are) continuously recruited from four clinical centres in Germany (Berlin, Tübingen, Ludwigshafen) and Austria (Innsbruck). The major aspect was:
• Can annexin A3 provide a better specificity than tPSA, in particular in the grey zone of PSA (2-10 ng/ml) and can annexin A3 thus contribute to a significant reduction of invasive transrectal biopsies?
