VALIDITY OF THE PROSTATE SPECIFIC ANTIGEN TEST FOR PROSTATE CANCER SCREENING: FOLLOWUP STUDY WITH A BANK OF 21,000 SERA IN FINLAND
Accepted 15 June 2001.
Purpose
We investigate the validity of prostate specific antigen (PSA) as a screening test for prostate cancer.
Materials and Methods
A registry of serum samples drawn from 1968 to 1976 from 21,387 men was linked to the Finnish Cancer Registry. During followup from 1968 to 1991, 104 prostate cancers were identified. A matched case control design with incidence density sampling and nested in the serum sample bank was applied, and PSA was assessed.
Results
The estimated sensitivity of the test was 44% and specificity 94% at a cutoff of 4.0 μg./l. in the total material. The sensitivity had improved to 86% in patients diagnosed in 5 years after the sample drawing. The test had a better sensitivity (93%) and specificity (96%) in men younger than 65 years at the time of the sample drawing compared to those older. The sensitivity further improved to 100% with a cutoff of 2.5 μg./l.
Conclusions
PSA is a valid screening test for prostate cancer, which compares favorably with mammography for breast cancer. However, until an effect on mortality has been shown, routine screening cannot be recommended.
From the Department of Public Health, Helsinki University, Tampere University School of Public Health, Finnish Cancer Registry, University Hospital of Helsinki, The National Public Health Institute, Helsinki, Finland
ABSTRACT