PSA screening lowers metastatic prostate cancer risk

In asymptomatic middle-age and older men, the use of prostate specific antigen (PSA) screening reduces the subsequent chances of developing metastatic prostate cancer, Canadian researchers report in the August issue of the Journal of Urology.

Lead investigator Dr. Jacek A. Kopec told Reuters Health, “there was a 35% reduction in risk among those who were screened. Further,” he added, “we observed a reduction in risk for both men under 60 years of age and those 60 years or greater, although the effect appears to be stronger in younger men.”Dr. Kopec of the University of British Columbia, Vancouver and colleagues conducted a population-based study involving 236 cases of metastatic prostate cancer and 462 controls drawn from the metropolitan Toronto area.Based on medical records, overall, the frequency of screening was significantly lower in men with prostate cancer than in control subjects (odds ratio, 0.65). In those between 45 and 59 years, the corresponding ratio was 0.52. In men between 60 and 84 years old, it was 0.67.Dr. Kopec added that “a key issue in the debate about the role of PSA screening has been the lack of evidence such screening is effective. We believe our study contributes to this debate in an important way because it offers new evidence that screening with PSA can reduce the risk of death from prostate cancer — the evidence is indirect as the outcome we looked at was metastatic cancer rather than death.”In an accompanying editorial, Dr. Gerald L. Andriole of Washington University School of Medicine, St. Louis, Missouri, broadly agrees, pointing out that “few urologists would have difficulty in accepting the notion that PSA screening results in detection of prostate cancer before it becomes metastatic.”(Source: J Urol 2005;174:413-414,495-499: Reuters Health: Oncolink: September 2005.)