What will the emperor say? Screening for prostate cancer as of 2008.

Screening for prostate cancer with prostate-specific antigen remains controversial approximately 20 years after its introduction into routine clinical care. Although numerous research studies have generated evidence to support or refute a benefit of screening, very few reports focus on the most relevant outcome of reducing mortality, and even fewer use rigorous methods of patient-oriented research. In addition, the tendency for personal beliefs (among investigators) to influence the interpretation of data introduces further complexity. Two major randomized trials evaluating the association of screening for prostate cancer and mortality are ongoing, and the results from these trials are anticipated as if an "emperor" was about to make a pronouncement. In reality, however, the expectation of a definitive answer from these trials may overlook methodological problems and underestimate the uncertainty inherent in scientific investigations. As of 2008, the need to counsel patients regarding the possible benefits and harms that can result from screening for (and treating) prostate cancer remains justified.