Prostate cancer is a serious worldwide problem. It is estimated that one in six men in the United States will be diagnosed with prostate cancer, and one in thirty-four will die of it. PSA (Prostate Specific Antigen) is a protein produced by the cells of the prostate gland. PSA helps liquefy the semen, thus it is a necessary chemical to help a man father a child. PSA is present in both benign and cancerous cells; however PSA in generally is higher when cancer is present. For this reason PSA has been used as a screening test for prostate cancer, but there are problems - it simply isn't as accurate of a test as men would like.

The Good

• Screening for prostate cancer is easy - a simple blood test (PSA) and digital rectal exam.
• The PSA blood test is relatively inexpensive and covered by Medicare and most insurance.
• Prostate cancer is found earlier with PSA testing. Prostate cancer is easier to treat when found early. It is not curable when it has spread.
• PSA levels normally rise with age as the prostate enlarges, but at a slow rate. Thus low and slowly rising levels of PSA indicate the risk of prostate cancer is minimal; this can be very reassuring for men to know.
• The number of deaths from prostate cancer has decreased in the past 20 years, since PSA testing has been popularized.
• There is no other screening blood test as accurate as PSA which screens for any other type of cancer in either men or women.
• Prostate cancer usually causes no symptoms. An elevated PSA test is usually the first sign.
• PSA is about ten times more accurate than a digital rectal exam for detecting prostate cancer.
• There are newer, more accurate forms of PSA and other markers for prostate cancer screening (tissue, urine and blood) that are being developed.

The Bad and the Ugly

• While a PSA test is simple, to actually diagnose prostate cancer a biopsy is required. This is more uncomfortable and costly.
• The newer PSA tests, and other screening tests being developed, are often not commercially available or have not yet demonstrated proven benefits.
• PSA testing is not accurate, since in general three of four men who undergo biopsy for an elevated PSA DO NOT have prostate cancer.
• PSA testing cannot tell the difference between prostate infection, benign enlargement, or cancer.
• PSA testing may lead to the overdiagnosis of a tumor that was not a real threat. This can lead to unnecessary treatments, which generally lower the quality of a man's life.
• It has not been proven whether PSA testing (vs. better treatments) has led to the decrease in deaths from prostate cancer.
• There are confusing recommendations from physician groups. Some (American Cancer Society) say every man aged 50 should be screened with a PSA; others (Centers for Disease Control) do not recommend it at all.
• While the risk of cancer increases with higher PSA levels, there is confusion about PSA cutoffs - there is no "normal PSA" where the risk of cancer is zero.

In conclusion, men should realize that PSA screening for prostate cancer is controversial, and that an elevated PSA does not necessarily mean there is prostate cancer present. While there does not seem to be a perfect PSA cutoff level, there should be more concern with a higher and more rapidly rising PSA. Urologists and most cancer specialists recommend screening (PSA test and digital exam) at age 50; sooner if there is a strong history of prostate cancer.