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Categories > Cancer > Prostate cancer

Test prep

The prostate-specific antigen (PSA) test is a blood test used to look for signs of prostate cancer in men. The prostate, located underneath the bladder and in front of the rectum, makes some of the fluid that protects sperm in semen. The higher the PSA level, the greater the odds that cancer is present.

The American Cancer Society (ACS) recommends that healthcare providers offer the test to patients beginning at age 50 (Medicare covers the test for this age group) and test high-risk men beginning at age 45. But once you turn 75, the risks of screening—and treatment—may outweigh the benefits. You’re more likely to develop prostate cancer if you:

  • are age 65 or older
  • have a father or a brother with prostate cancer
  • are African-American (Asian and Native American men have the lowest risks)
  • eat a diet high in fat (particularly animal fat)

Although testing may help detect prostate cancer early, many cancers are slow-growing and never spread beyond the prostate gland. Unfortunately, the PSA test can’t tell you which type you have. Other problems with the test: It often says you have cancer when you don’t. And other factors such as aging, infection or prostate enlargement can affect PSA levels. By having unnecessary treatment, such as surgery or radiation, on a non-aggressive form of cancer, you may risk serious side effects like urinary incontinence, erectile dysfunction or bowel dysfunction.

An alternate option

Many healthcare providers also perform a digital rectal exam (DRE), in which they insert a gloved, lubricated finger into the rectum to check for signs of prostate cancer. It’s not as effective as a PSA test, but sometimes it finds cancer in men who have normal PSA levels. Ask your healthcare provider to help you decide when and if you should be tested, and visit the ACS Web site at for more information about prostate cancer prevention and screening.