prostate cancer screens

Approximately 186,000 men in the United States are diagnosed with prostate cancer every year. Most of those diagnoses start with a screening test: either a digital rectal exam, during which a doctor feels the prostate to check for irregularity or enlargement, with a blood test to check the level of prostate-specific antigen, or PSA, in the blood, or both.

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Prostate cancer: What you need to know


Tests don't clearly indicate cancer
But these tests, especially the PSA, are indirect markers. The PSA doesn’t check for cancer, it checks for a protein that may signal cancer is present. The higher the PSA, the greater the risk. But because PSA doesn’t prove cancer, invasive tests, like biopsies, are required to diagnose disease. Even then, doctors can’t always be sure what kind of prostate cancer a man has — whether it will be very slow-growing and never cause a problem, or whether it will be life-threateningly aggressive.