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? continued...
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."
Andriole agrees with Lilje that the study findings must be confirmed in future studies with men from different ethnic groups. But he's excited about the implications.
"Maybe we can now target the men most likely to develop lethal prostate cancer and forget about men at very low risk," Andriole says. "Using the PSA test at late middle age, it segregates those who need further screening in a reasonable way. It is obviously not going to be perfect, but it is a good way to go."
The Lilje study also appears in the Sept. 14 online issue of BMJ.
Should Men Undergo PSA Testing?
So should men undergo PSA screening for prostate cancer? That remains a personal decision, Dahm says. But it is a decision that should not be made until a man has thoroughly discussed the possible benefits and possible harms with his doctor.
"People differ in their values and in their preferences and in what is important to them," Dahm says. "There clearly are men who, even if this is irrational, if they have prostate cancer they just want to know. But it is very important that we neither overrate nor underrate PSA screening. Our job as doctors is not to tell them what to do, but to provide them with accurate information."
And if a PSA test is high -- or even if a biopsy detects early prostate cancer -- Andriole advises men not to jump to conclusions, but to carefully consider their options.
"I would encourage patients with elevated PSA or with a prostate cancer diagnosis to really do a lot of homework, to ask a lot of questions, and to get familiar with the real terrain of early prostate cancer," he says. "You have time to make an informed decision. The resources to guide you are out there. Try not to get overly emotional and feel like you have to do something immediately."