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What is PSA?

J. Beam
J. Beam

You may have hear the term PSA used in conjunction with a lab report following a routine physical. PSA is a commonly used medical acronym that stands for prostate-specific antigen. It is a protein found in the blood, and while it is normally present in low levels in men, high levels of PSA can indicate disease affecting the prostate. It is often used as an indicator for prostate cancer, but higher than normal levels can also indicate benign conditions.

A PSA test is often used as part of a prostate cancer screening process. The levels are measured by drawing blood and sending the blood to a laboratory for testing. There appears to be no universal agreement about the “normal” range of PSA levels, as the accepted maximum level of the normal range changes with age. It was once thought that 4 or below was an acceptable normal range in any man, but when used as an indicator for cancer, this may or may not be accurate. PSA levels are only one indicator, however, and regular prostate screenings and physical exams are also used to help evaluate risk.

Prostate specific antigen levels help screen for possible prostate cancer.
Prostate specific antigen levels help screen for possible prostate cancer.

PSA levels are a useful diagnostic tool, but it is not a foolproof indicator. Most urologists and oncologists do not rely solely on PSA tests to diagnose the risk or presence of cancer. PSA tests are typically performed as part of routine screenings and also as a monitoring tool to determine the effectiveness of prostate cancer treatment. For instance, if a man is diagnosed with prostate cancer and begins treatment but PSA levels continue to rise or do not decrease, it may indicate the treatment isn’t working or the cancer is growing.

A man's prostate can be found around the urethra.
A man's prostate can be found around the urethra.

PSA tests may be recommended for men between the ages of 40 and 75 as part of their routine health care, but not all doctors believe in regular testing without the presence of other symptoms. A blood test alone is not a guaranteed indicator of prostate cancer. Some men test with higher than normal levels and do not have cancer, while others who have consistently low levels have developed prostate cancer. Other factors, such as family history and abnormal or enlarged prostate gland are usually considered. Only about 1 in 4 men who test positive for high PSA actually have prostate cancer. Since it is a slow-growing cancer, men over 75 generally don’t need their PSA levels monitored.

PSA tests may be recommended for men who have a family history of an enlarged prostate gland.
PSA tests may be recommended for men who have a family history of an enlarged prostate gland.

A simple blood test is all that is necessary to test PSA levels; your doctor can help you decide if you should have a PSA test. Regular physicals and good communication with your doctor can help you relieve any concerns you may have about developing or detecting prostate cancer.

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    • Prostate specific antigen levels help screen for possible prostate cancer.
      By: jarun011
      Prostate specific antigen levels help screen for possible prostate cancer.
    • A man's prostate can be found around the urethra.
      By: peterjunaidy
      A man's prostate can be found around the urethra.
    • PSA tests may be recommended for men who have a family history of an enlarged prostate gland.
      By: peterjunaidy
      PSA tests may be recommended for men who have a family history of an enlarged prostate gland.
    • A PSA test is often used as part of a prostate cancer screening process.
      By: nyul
      A PSA test is often used as part of a prostate cancer screening process.
    • A PSA test can be done by drawing blood and sending it to a lab for testing.
      By: hadkhanong
      A PSA test can be done by drawing blood and sending it to a lab for testing.
    • High levels of PSA can be an indicator of prostate cancer.
      By: peterjunaidy
      High levels of PSA can be an indicator of prostate cancer.