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PSA tests: Just how reliable?: The pros and cons of prostate cancer screening
The screening debate
To treat or not to treat

When to test for prostate cancer
When to test for prostate cancer

The American Cancer Society recommends getting the prostate specific antigen blood test and a digital rectal exam yearly starting at:

  • age 50 for men who have at least a 10-year life expectancy
  • age 45 for men at high risk, such as African-Americans and men who have one or more first-degree relatives (a father or brother) diagnosed with prostate cancer at an early age (younger than 65)
  • age 40 for men at even higher risk, due to multiple first-degree relatives affected at an early age

You’ve seen the ads urging you to be screened for prostate cancer. When you ask your doctor about the screening, he or she tells you the prostate specific antigen, or PSA, test may not detect cancer or can lead to unnecessary treatments that may tax you physically and emotionally. Yet your doctor reminds you that prostate cancer doesn’t cause symptoms until it’s advanced. And cancer that’s not caught early can spread outside the prostate gland to other parts of the body.

So what should you do to beat the second deadliest cancer (after lung cancer) among American males, affecting almost 186,000 men and claiming more than 28,000 lives each year?

The screening debate

Considered by many healthcare professionals to be a reliable indicator of prostate cancer, the PSA test detects the amount of a substance in the blood secreted by the prostate gland. High PSA levels can indicate cancer.

But PSA levels rise for other reasons, too, such as inflammation, normal prostate enlargement, age and drug reactions, which can all cause false or inconclusive results. And if it is cancer, it may be harmless or slow-growing. But since the PSA test can’t distinguish between harmless and dangerous cancers, the only way to be sure about the cancer’s potency is to perform costly—and uncomfortable—testing or treatment. What’s more, the test can sometimes miss cancer in overweight and obese men since carrying excess weight can lower PSA levels.

In some cases, when PSA levels are high, doctors wait for a period of time and then retest. If PSA levels are elevated even more, chances are that an aggressive cancer is present once other possible causes of a high result are ruled out.

The American Cancer Society recommends that men, before they decide to take the PSA test, should understand that the screening reports a high number of false positives as well as medically insignificant tumors.

To treat or not to treat

It’s not clear whether treatment will help all men with prostate cancer live longer. Prostate cancer tends to grow slowly in older men. In many cases, a man is more likely to die of something other than prostate cancer—especially among those who had less than a 10-year life expectancy before they were diagnosed. An older man diagnosed with cancer who opts for treatment may undergo radiation therapy or surgery to remove the prostate—therapies that can cause impotence, incontinence and painful urination. Some effects disappear over time; others may be permanent.

Nevertheless, prostate cancer can be aggressive, and men, both young and old, do die from it. The bottom line is that both patients and doctors must decide if the benefits of cancer treatment will outweigh its side effects.