The PSA test is a blood test used to detect prostate cancer. Doctors suspect prostate cancer if the blood contains high levels of a protein called prostate-specific antigen. For men who want to be screened for prostate cancer, the test is usually done every year beginning between ages 40 and 50, depending on individual risk factors.
PSA testing to screen for prostate cancer might seem like a no-brainer. However, the test has become controversial. If a man’s PSA is elevated, he’ll likely undergo a biopsy and, if cancer is diagnosed, invasive treatment. But because most prostate cancers grow slowly, they aren’t likely to affect the man during his lifetime. In addition, experts no longer recommend routine PSA screening for men ages 75 and older because they are more likely to die from another condition than from undetected prostate cancer.