Evidence Report Suggests Prostate Screening Does Not Reduce Prostate Cancer or All-Cause Mortality

FINDINGS:

• Prostate cancer screening did not result in a statistically significant reduction in prostate cancer-specific or all-cause mortality.
• One of the studies in this review showed a marginally significant benefit for prostate cancer screening among a subgroup of men aged 55 to 69. Among this group, it was reported that 1,410 men would need to be screened, with 48 men needing prostate cancer treatment, to prevent one additional death from prostate cancer during a 9-year period.
• Any benefits from prosate cancer screening may take up to 10 years to accrue; therefore, the authors suggest that men with a life expectancy of less than 10 to 15 years should be informed that screening for prostate cancer is unlikely to be beneficial.
• None of the studies reviewed provided detailed assessment of the effect of screening on quality of life or costs associated with screening.

BACKGROUND:
Prostate cancer is a leading cause of morbidity and mortality, but screening for this disease requires that diagnostic tests be performed in the absence of any symptoms or indications of the disease. Screening for prostate cancer has generated considerable debate within the medical and broader community, as demonstrated by varying guideline recommendations. Much of this debate is due to the limited availability of high quality research and the influence of false-positive or false-negative results generated by the use of screening techniques, i.e., digital rectal exam (DRE) and prostate-specific antigen (PSA) blood test. In a 2006 review of the evidence conducted by the authors, they identified insufficient evidence to either support or refute the use of routine screening for prostate cancer. This article presents findings from their updated study, in which investigators sought to determine whether population-based screening reduces prostate cancer-specific mortality and/or all-cause mortality. They also examined its impact on quality of life, including adverse events (e.g., harms of screening from false-positive or false-negative results). Conducting an evidence-based review of the literature, investigators report on five (non-VA) randomized controlled trials with a total of 341,351 participants. The age of participants ranged from 50 to 74, and duration of follow-up from 7 to 15 years.

IMPLICATIONS:

• The authors suggest the need for further long-term follow-up from existing trials to gain a better understanding of the impact of screening on adverse events, quality of life, and medical care costs. Additional research also is required to further identify the psychosocial aspects of screening, patient knowledge and uptake of screening, as well as clinician perspectives and needs with respect to screening.

AUTHOR/FUNDING INFORMATION:
Dr. Wilt is part of HSR&D’s Center for Chronic Disease Outcomes Research, Minneapolis, MN.

Ilic D, O’Connor D, Green S and Wilt T. Screening for Prostate Cancer. Cochrane Database of Systematic Reviews September 2010