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The Prostate

The Prostate
Prostate Gland Enlargement
PSA Test
Prostate Cancer

PSA Test (Prostate-Specific Antigen Test)

      The prostate-specific antigen (PSA) test was developed and approved by the FDA in 1986. It is a test that is designed to help detect prostate cancer, and to monitor men with a history of prostate cancer for any reoccurrence of the disease.

PSA is an enzyme that produced by cells in the prostate gland. It acts to assist in liquefying semen by dissolving the proteins that promote clumping in semen. A doctor can identify a number of problems relating to the prostate by testing the amount of PSA circulating in the bloodstream. This test is performed using a small blood sample taken from the arm.

PSA Levels

Small amounts of PSA in the bloodstream (from 0-4.0 nanograms per milliliter) is considered normal. What is considered normal changes in relation to a man's age, as PSA levels tend to climb a small amount as men get older.

Prostate PSA levels higher than 4.0 can indicate a problem, including prostate inflammation (prostatitis), infection, prostate gland enlargement (benign prostatic hyperplasia), or cancer. Approximately 30% of men showing elevated PSA levels have cancer. It is important to note that some men without any prostate problems show PSA levels higher than normal, and 20% of prostate cancers develop while PSA levels are in the 'normal' range.

Heightened PSA levels do not indicate prostate cancer on their own and cannot distinguish between benign prostate conditions and cancer. High PSA levels will indicate to a physician that further tests should be administered to detect other signs of prostate cancer.

PSA Testing

Professionals have varying opinions on the value of PSA testing. The test itself is not perfect and carries with it some risks and benefits. Benefits of the PSA test include:

- detecting prostate cancer long before any symptoms present themselves
- early detection makes treating the cancer easier
- the test has contributed to a significant reduction in prostate cancer deaths

Some negatives of the PSA test include:

- in approximately 20% of cases, PSA tests show 'normal' PSA levels in men with early prostate cancer (false-positive)
- the test itself does not distinguish between prostate cancer and other prostate problems
- 2 out of 3 of those with elevated levels of PSA do not have prostate cancer, causing undue worry
- men over the age of 75 do not benefit from the test, as treating prostate cancer in men past age 75 is unlikely to lengthen lifespan

The FDA approved the PSA test to monitor patients with a history of prostate cancer. A rise in PSA levels for these patients can indicate a reoccurrence of the cancer, indicating a biochemical relapse that can precede any symptoms of relapse by months and even years. A single rise in PSA levels for these patients doesn't guarantee a recurrence of prostate cancer, and doctor's will often perform several tests to detect a trend of rising PSA measurements.

Doctors disagree about when and how frequently PSA testing should be carried out. Annual PSA screening is generally recommended for men past the age of 50; however, patients with a family history of prostate problems may be advised to begin screening at age 40-45. There are doctors who advise against routine screening at all, citing the potential risks involved.

The Digital Urology Channel offers information about the prostate and prostate gland diseases and conditions. The Prostate Cancer Coalition website is an excellent resource for those managing the disease.

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