ATLANTA — A single prostate-specific antigen screening measurement of 3 ng/mL or higher is sufficient to justify a biopsy of the prostate without a repeat measurement of the PSA, researchers reported at the annual meeting of the American Urological Association.
Traditional wisdom has been that the serum PSA, if elevated, should be measured again before biopsy, on the theory that PSA levels could normalize before the second test. This premise is not valid, said Dr. Freddie C. Hamdy, head of urology at Sheffield (England) University.
He reported data from the ongoing Prostate Testing for Cancer and Treatment (Protect) study, a large randomized controlled trial in the United Kingdom. The study is scheduled to complete recruitment in 2008.
He and his associates analyzed the value of a repeat PSA test in 7,383 asymptomatic men aged 50–69 years during the feasibility phase of the Protect study. PSA testing was done between 1999 and 2001. Of the men, 723 (10%) had a PSA level of at least 3 ng/mL. All of these men were biopsied after the first PSA test, and 224 (31%) were found to have cancer. Repeat PSA measures were performed, but it was the first measure that triggered the biopsies.
If the criterion of PSA normalization had led to deferred biopsy, prostate cancer would have been missed in 8.1% of men biopsied after a PSA level of 3 ng/mL or higher and in 11.1% of men biopsied after a PSA level of 4 ng/mL or higher.
Cancer could be missed in 8.1% of men biopsied after a PSA level of 3 ng/mL or higher that later normalized. DR. HAMDY