Cloud of Doubt Surrounding the PSA Test

Many men take the PSA test--a blood test used to help diagnose prostate cancer--without thinking twice. This can be a mistake.

Cancer specialists are deeply divided over when the PSA is appropriate, and for whom. The American Cancer Society, for instance, urges men to talk to their doctors about it after age 50. The National Cancer Institute, however, has not issued guidelines at all.

Why not? Because it is not yet clear that early PSA screening has reduced the mortality rate for prostate cancer. In most men, the cancer grows so slowly that they will die of something else first.

And even a slightly elevated PSA often sets in motion a train of further diagnostic testing, including ultrasound probes, needle biopsies and ultimately surgery--costly and emotionally trying experiences that are sometimes unnecessary.

The PSA has undoubtedly saved many lives, doctors say. But it has also led to plenty of unwarranted surgery.

So while high-profile patients, such as Bob Dole, have called the PSA a lifesaver, some doctors who have studied the test refuse to submit to one themselves. “I’m 56, and I still haven’t had one,” says Paul Nutting, a Denver family physician who has studied prostate cancer diagnosis and treatment. “That’s a decision I’ve made for myself. I’m not saying it’s right for everyone.”

If you do take the test, it’s a good idea to know what the PSA actually measures. The test detects blood levels of a protein called prostate-specific antigen, made only by prostate cells. When the prostate swells a little, as often happens in men over 50, the PSA edges upward. If the gland expands even more, as it does in a common condition called benign prostate hyperplasia, the PSA increases more. And if the gland develops cancer, PSA levels usually surge noticeably upward--usually, but not always.

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Some men’s prostates produce so little PSA that even a cancer wouldn’t push their level over 4. Others’ glands naturally produce so much that it appears they have cancer when they don’t. Some medications may also affect the PSA reading. That’s why more doctors are using the change in PSA levels, over time, as a guide to diagnosis.

“One elevated score just scares the dickens out of people,” says Nutting, “and it may mean nothing.”

The PSA can be reassuring, when it’s negative. And when it’s positive, the test can give a man the chance to cure a cancer that would otherwise be deadly.

The test is a must only for certain high-risk groups: African-Americans, for example, who run a much higher risk than whites for the cancer, and any man whose father, brother or uncle died of the disease. The American Cancer Society urges these men to begin thinking about the test as early as age 40. Everyone else has to decide for himself.