Screening for prostate cancer

Abstract

Background: Any form of screening aims to reduce mortality and increase a person's quality of life. Screening for prostate cancer has generated considerable debate within the medical community, as demonstrated by the varying recommendations made by medical organizations and governed by national policies. 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 use of the diagnostic techniques such as the digital rectal examination (DRE) and prostate specific antigen (PSA) blood test.

Objectives: To determine whether screening for prostate cancer reduces prostate cancer mortality and has an impact on quality of life.

Search strategy: Electronic databases (PROSTATE register, CENTRAL the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CANCERLIT and the NHS EED) were searched electronically in addition to hand searching of specific journals and bibliographies in an effort to identify both published and unpublished trials.

Selection criteria: All randomised controlled trials of screening versus no screening or routine care for prostate cancer were eligible for inclusion in this review.

Data collection and analysis: The search identified 99 potentially relevant articles that were selected for full text review. From these 99 citations, two randomised controlled trials were identified as meeting the review's inclusion criteria. Data from the trials were independently extracted by two authors.

Main results: Two randomised controlled trials with a total of 55,512 participants were included; however, both trials had methodological weaknesses. Re-analysis using intention-to-screen and meta-analysis of results from the two randomised controlled trials indicated no statistically significant difference in prostate cancer mortality between men randomised for prostate cancer screening and controls (RR 1.01, 95% CI: 0.80-1.29). Neither study assessed the effect of prostate cancer screening on quality of life, all-cause mortality or cost effectiveness.

Authors' conclusions: Given that only two randomised controlled trials were included, and the high risk of bias of both trials, there is insufficient evidence to either support or refute the routine use of mass, selective or opportunistic screening compared to no screening for reducing prostate cancer mortality. Currently, no robust evidence from randomised controlled trials is available regarding the impact of screening on quality of life, harms of screening, or its economic value. Results from two ongoing large scale multicentre randomised controlled trials that will be available in the next several years are required to make evidence-based decisions regarding prostate cancer screening.