http://www.ncbi.nlm.nih.gov/pubmed/23269114

Med Care. 2012 Dec 23. [Epub ahead of print]

Limitations of Basing Screening Policies on Screening Trials: The US Preventive Services Task Force andProstate Cancer Screening.

Etzioni R, Gulati R, Cooperberg MR, Penson DM, Weiss NS, Thompson IM.

Source

*Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA †Department of Urology, UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA ‡Vanderbilt University Medical Center, Nashville, TN §Department of Epidemiology, University of Washington, Seattle, WA ∥Department of Urology, University of Texas, San Antonio, TX.

Abstract

BACKGROUND:: The US Preventive Services Task Force recently recommended against prostate-specific antigen screening for prostate cancerbased primarily on evidence from the European Randomized Study of Screening for Prostate Cancer (ERSPC) and the US Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. OBJECTIVE:: To examine limitations of basing screening policy on evidence from screening trials. METHODS:: We reviewed published modeling studies that examined population and trial data. The studies (1) project the roles of screening and changes in primary treatment in the US mortality decline; (2) extrapolate the ERSPC mortality reduction to the long-term US setting; (3) estimate overdiagnosis based on US incidence trends; and (4) quantify the impact of control arm screening on PLCO mortality results. RESULTS:: Screeningplausibly explains 45% and changes in primary treatment can explain 33% of the US prostate cancer mortality decline. Extrapolating the ERSPC results to the long-term US setting implies an absolute mortality reduction at least 5 times greater than that observed in the trial. Approximately, 28% of screen-detected cases are overdiagnosed in the United States versus 58% of screen-detected cases suggested by the ERSPC results. Control arm screening can explain the null result in the PLCO trial. CONCLUSIONS:: Modeling studies indicate that population trends and trial results extended to the long-term population setting are consistent with greater benefit of prostate-specific antigen screening-and more favorable harm-benefittradeoffs-than has been suggested by empirical trial evidence.