[New challenges and earlier approved methods in the laboratory diagnosis of prostate cancer]

Prostate cancer is usually a disease of elderly men, however, over 40 years of age the tumor can appear at any times. PSA is a protein molecule synthesized by prostate cells. Measurement of serum PSA has revolutionized the diagnosis and treatment of prostate cancer. However, PSA is not sufficiently specific for the detection of prostate cancer, since serum PSA might also be elevated in benign prostate diseases, as well as following physical stimulation of the gland (digital rectal examination, biopsy, catheterization, or even ejaculation). To increase the specificity of PSA, different derivative parameters have been developed i.e. PSA density (ratio of PSA to prostate volume), PSA velocity (change of PSA over a time period) or age-specific reference ranges. 65-95% of circulating PSA is bound to different proteins, while the rest of PSA circulates in a non-bound form (free PSA, fPSA). In addition to fPSA, the prostate health index [phi; (-2)proPSA/fPSA×√PSA] is increasingly used to differentiate between carcinoma-induced and non-carcinoma-induced increase in PSA. PCA3 is a non-coding messenger RNA, which is 60-70-fold overexpressed by cancer cells in the prostate. Measurement of urine PCA3 appears to be more sensitive than %tPSA, and is independent of prostate volume, age or tPSA. The author reviews laboratory biomarkers related to prostate cancer, used either in the routine clinical practice, or in research. Laboratory biomarkers seem to be useful tools to reduce the incidence of advanced stage, or metastatic prostate cancer, and the cancer-related death rate. A promising perspective for the future is the detection of circulating prostate cancer cells and the profiling of microRNAs, especially on the field of tumor prognosis.