Prostate cancer mortality in relation to screening by prostate-specific antigen testing and digital rectal examination: a population-based study in middle-aged men.

BACKGROUND

Although prostate cancer screening by measurement of serum prostate-specific antigen (PSA) and digital rectal examination (DRE) is common in clinical practice, the impact of such screening on prostate cancer-specific mortality remains uncertain.

METHODS

Data from a population-based case-control study in King County, Washington, among men aged 50-64 years (706 cases, 645 controls) were used to examine the relationships between PSA and DRE screening and fatal prostate cancer and other-cause mortality. Incident cases were diagnosed in 1993-1996, identified via the Seattle-Puget Sound SEER cancer registry and followed for vital status through 1 June 2007. Controls were ascertained by random digit dialing and frequency age-matched to cases. The screening variable used in this analysis was self-reported receipt of one or more PSA and/or DRE tests performed as part of a routine checkup in the five-year period before diagnosis or reference date.

RESULTS

A smaller proportion of men with fatal prostate cancer had one or more PSA and/or DRE screening tests compared to controls, resulting in an adjusted odds ratios (OR) of 0.38 (95% CI 0.19-0.77). There was no association, however, between PSA and/or DRE screening and other-cause mortality (OR = 1.02; 95% CI 0.51-2.02).

CONCLUSIONS

Results of this study suggest a reduction in prostate cancer-specific mortality associated with PSA and/or DRE screening in middle-aged men. Findings should be interpreted cautiously, however, as results are based on observational data. Further, the study was not able to separate the relative efficacy of PSA versus DRE screening.