PSA Tests for Prostate Cancer May Not Save Lives
Study Shows Routine PSA Tests Don't Cut Deaths; First Test at Age 60 May Be Best for Most
1 PSA Test at Age 60?
The key question for men is not whether they have prostate cancer, suggests Hans Lilja, MD, PhD, of New York's Memorial Sloan Kettering Cancer Center. What they need to know is whether the cancer will cause symptoms or shorten their lives.
Lilja and colleagues wondered whether the PSA test could help men answer this question. To that end, they looked at a unique set of data collected from some 1,200 60-year-old Swedish men who donated blood plasma in a 1982 study of heart disease.
The researchers tested the blood for PSA levels. Then they matched the results to the men's medical records.
If men who had this single PSA test at age 60 had a PSA level of 1 ng/ml or less, they had a small chance of metastatic or fatal prostate cancer. By age 85, only 0.5% of these men had metastatic prostate cancer and only 0.2% of them had died of prostate cancer.
But men with age 60 PSA levels higher than 2 ng/ml were 17 times more likely to have metastatic prostate cancer by age 85 and 26 times more likely to die of prostate cancer than men with PSA levels below 2 ng/ml.
While 90% of the prostate cancer deaths by age 85 were in the men with an age-60 PSA level over 2 ng/ml, the finding was by no means a death sentence. Even among the 5% of men with the highest age-60 PSA levels -- at least 5.2 ng/ml -- only one in six died of prostate cancer.
Lilje tells WebMD that about half of men will have a PSA level of less than 1 ng/ml at age 60. If the study findings are validated in future studies, he says, it means that these men will never need another PSA test.
"Instead of screening everyone every year regardless of their PSA level the year before, you remove half -- those with a PSA below 1 -- because they would not benefit at all," Lilje says. "Instead, you would focus most of your effort on men with a PSA above 2, because they have the greatest chance of benefit."