[Advancements in PSA-based screening for prostate cancer].

As the most frequently diagnosed cancer and the second leading cause of cancer death in most Western countries, prostate cancer represents a significant health care problem. The introduction of routine prostate-specific antigen (PSA) screening for asymptomatic men is still controversial. To solve uncertainties regarding the screening for prostate cancer, prospective randomized controlled trials are ongoing in the USA and Europe. The development of an optimal screening system may be one of the most important issues for screening for prostate cancer, and it should be set not only for reducing the mortality rate of prostate cancer, but also for reducing the cost. The best screening modality for the 1st step of mass screening for prostate cancer is the PSA test. Furthermore, the cut-off value should be set in an age-specific manner. The risk of developing prostate cancer in men with PSA levels of 4.0 ng/ml or lower increases when the baseline PSA levels are higher. Therefore, re-screening for men without suspicious findings for prostate cancer at the 1st step of screening should be set relative to the baseline PSA and digital rectal examination status. In the 2nd step of screening, the PSA density adjusted by the transition zone volume (PSATZD) and free/total PSA ratio (%f-PSA) may be useful in the selecting patients who should be biopsied. The optimal cut-offs for PSATZD and %f-PSA have not been confirmed, however, and an age-adjusted setting should be considered to detect clinically significant cancer. The method of prostate biopsy is also very important for improving the diagnostic accuracy for prostate cancer. The number of biopsy cores should be set relative to prostate volume. Furthermore, the clinically significant tumor volume may be smaller in younger men than in older men. Therefore, the optimal number of biopsy cores should be set according to age and prostate volume. Both an optimal screening system and minimally invasive treatments will be available in the future, and screening for prostate cancer may be more useful for elderly males.