AUA: One PSA Measurement Has 25 Years of Predictive Value

ANAHEIM, Calif., May 22 -- A single PSA measurement in middle age can predict a prostate cancer risk up to 25 years later, results of a large Swedish study suggest.

An analysis of archived serum samples from 21,277 men showed a strong association between prostate specific antigen values and subsequent risk of prostate cancer. In particular, more than 60% of advanced prostate cancers (T3 M+) that developed over a 25-year period were associated with PSA values in the 80^th percentile or greater among men ages 44 to 50, said Hans Lilja, M.D., of Memorial Sloan-Kettering Cancer Center in New York.

The finding further solidifies the role of PSA assessment in the routine care of men. "In this large unscreened representative population, a single PSA measure at age 44 to 50 was a very strong predictor of later diagnosis of prostate cancer of unquestionable significance," Dr. Lilja reported at the American Urological Association meeting here.

"Our data need to be evaluated in independent study cohorts," he acknowledged, "but the results raise the question of whether screening and chemoprevention efforts should be risk stratified to focus on men who are at the highest risk for advanced prostate cancer."

Data for the analysis came from archived samples collected in Malmo, Sweden, between 1974 and 1986. As of Dec. 31, 1999, 161 men had developed prostate cancer that was already advanced at the time of diagnosis. The patients' PSA values were compared with those of approximately 500 age-matched controls.

Dr. Lilja and his associates examined the predictive value of total PSA, free PSA, and the serine protease kallikrein-2, a cancer biomarker. All three laboratory parameters correlated significantly with subsequent risk of advanced prostate cancer (P