Prostate-Specific Antigen (PSA) Test

June 4th, 2009

Definition:
A man’s prostate produces a protein called “prostate-specific antigen” that can be measured in the blood. Some diseases, including prostate cancer, cause the prostate to make a larger quantity of this protein. By measuring prostate-specific antigen levels in your bloodstream, doctors may be able to find prostate cancers in their early stages.

……………………………..

Doctors still disagree about whether it is a good idea for all men to have this test done after they turn 50. One reason is that many prostate cancers that are found by the PSA test are destined to remain tiny areas inside the prostate gland, never to spread and cause medical problems. Discovering such cancers can cause great anxiety, if a man chooses to have no treatment for them. If a man opts for treatment, he may suffer the possible side-effects of treatment (such as loss of sexual function, or leakage of urine) in order to treat a cancer that would never have grown and spread.

At the same time, detecting cancers that are destined to spread at an early stage can be life-saving. Doctors are working hard on techniques that will distinguish those prostate cancers that are destined to spread, and those that are not. You should definitely discuss with your doctor the pros and cons of having this test done before you proceed.

A prostate-specific antigen (PSA) test measures the amount of prostate-specific antigen in the blood. PSA is released into a man’s blood by his prostate gland. Healthy men have low amounts of PSA in the blood. The amount of PSA in the blood normally increases as a man’s prostate(Click here to see an illustration. )enlarges with age. PSA may increase as a result of an injury, a digital rectal exam, sexual activity (ejaculation), inflammation of the prostate gland (prostatitis), or prostate cancer.

Prostate cancer often grows very slowly, without causing major problems. Detecting prostate cancer early and treating it may prevent some health problems and reduce the risk of dying from the cancer. However, some treatments for prostate cancer can cause other problems, such as controlling urination (incontinence) or erection problems (erectile dysfunction). Some men may choose not to have a PSA test or treat prostate cancer if it is detected. For example, a man older than age 75 who has no bothersome symptoms of prostate cancer may choose not to treat the cancer if it is found, so he would not need a PSA test.

Preparation for the test.
There is no special preparation for this test, but to avoid having an artificially high test level you should not have sexual intercourse for a day before your test. Tell your doctor if you are taking any medicines, especially medicines for the prostate, since these may affect the way the doctor interprets the results of your test.

Prior to Procedure:
* Ejaculation can cause levels of PSA to rise. Avoid sexual activity for 2-3 days before testing.
* Some tests can elevated PSA levels. Schedule your PSA test for several weeks after any of these tests:
o Cystoscopy
o Prostate needle biopsy
o Rectal exam of the prostate
* Wait several weeks after successful treatment of:
o Urinary tract infection
o Prostatitis
* Some medications can lower PSA levels. Tell your doctor if you are taking:
o Finasteride (eg, Propecia, Proscar)
o Dutasteride (eg, Avodart)

Description of the Procedure
You will roll up your sleeve. The person drawing blood will wrap an elastic band around your upper arm. He will clean your arm near the inside of your elbow with alcohol. Then, he will insert the needle. A small amount of blood will be drawn into a tube. Pressure will be applied to the puncture site with a gauze pad or cotton ball as the needle is removed. A small bandage may be placed on the site. Your blood will be sent to a lab for testing.

What happens when the test is performed?
A sample of your blood will be drawn from a vein. The level of prostate-specific antigen in your blood will be measured in the laboratory.

What risks are there from the test?
There are no risks from this test. As mentioned, however, this test can leave you with some difficult choices if it is abnormal.

Must you do anything special after the test is over?
After Procedure is over
*You can return to normal activities.
* Resume normal sexual activity.
* If a hematoma forms, place a piece of cotton over the area. Cover with a bandage. Make sure the pressure is firm.

How long is it before the result of the test is known?
Results from this test take several days to come back. Your doctor will have to decide whether the test level is normal for you by taking your age and other factors into consideration.

RESULTS:-
This table shows the classification of PSA levels:
Normal…………………….0-4 ng/mL
Slightly elevated………..4-10 ng/mL
Moderately elevated….10-20 ng/mL
Highly elevated…………20 ng/mL or higher
Note: These values may change as more research is done.
Resources:

https://www.health.harvard.edu/fhg/diagnostics/prostate-specific-antigen-test.shtml

http://www.health.com/health/library/topic/0,,hw5522_hw5525,00.html

http://healthlibrary.epnet.com/GetContent.aspx?token=a4c1f00b-d245-44f2-a90e-20b047f84a6a&chunkiid=29006