Background
The prostate-specific antigen (PSA) test was approved by the U.S. Food and Drug Administration in 1986, for
monitoring disease status in men with prostate cancer, and in 1992 for diagnosis. Once approved, the test was
also performed on men with urological symptoms as well as on those who were asymptomatic in an effort to diagnose
prostate cancer early and affect the mortality rate. Use of the test since 1986 was associated with a dramatic
rise in prostate cancer incidence in the early 1990s, followed by a subsequent decline. Incidence rates have
recently resumed the pre-PSA trend. The incidence of distant stage disease, which had been relatively flat,
started to decline dramatically in the early 1990s. Prostate cancer mortality also began to decline in the early
1990s, and the decline has continued. Randomized controlled trials have not yet confirmed the efficacy of PSA
testing, which raised the question of the role played by the PSA test in the recent mortality decline. It is
important to answer this question to provide the public and cancer researchers with an informed judgment about
the impact of the PSA test on vital statistics in light of a pattern in the rates that suggested a benefit from
use of the test.
About the Prostate Base Case
The two members of the CISNET Consortium who model prostate cancer are collaborating on a set of common simulations
to address the impact of PSA test on trends in prostate cancer mortality and incidence. In order to have comparable
answers, the groups agreed to have some common inputs into their models. The relevant age and years which are
of interest for reporting were defined to be ages 50-84 and years 1987-2000 (birth cohorts 1903-1950). As a
first pass, we will be modeling all races combined. At a second stage, the groups will add treatment dissemination
and efficacy, and evaluate the impact of both PSA and treatment dissemination, and their interaction in the
decline of prostate cancer mortality. Another issue to be addressed is the fact that prostate cancer incidence
in African-American men did not show a return to the secular (i.e., background) trend, as it did in white men.
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