A prostate specific antigen (PSA) blood test is done to measure the amount of total PSA present in your blood. PSA is a protein produced by the cells in your prostate gland. A PSA level higher than what your doctor considers normal may mean something is affecting your prostate. This could be a prostate that has simply enlarged due to age (a condition known as benign prostatic hyperplasia, or BPH), an infection or inflammation of the prostate, or prostate cancer. A very high PSA level strongly suggests prostate cancer.
What happens during a PSA blood test?
A sample of blood will be drawn from your vein. As with many blood tests, the blood is usually taken from a vein found in the arm. You do not need to fast (that is, refrain from eating and drinking) before the test. However, other activities can cause your PSA level to rise. Ejaculating 24 hours or less before your PSA test may give an elevated PSA test result. Exercise that may affect the prostate, such as bicycle riding or horseback riding, can also increase your PSA level. Therefore, you must avoid doing these activities before your PSA blood test.
After blood is drawn, your doctor will check if your PSA level is normal. Your PSA level may also be compared to the results of previous PSA blood tests you have had before. This is to see if your PSA level has increased significantly. If your PSA level has increased from the last time you had a PSA blood test, your doctor may also check how quickly it has done so. This is called the PSA velocity.
What is a PSA blood test used for?
Your doctor may recommend a PSA blood test if you come in with symptoms of BPH or prostate cancer. After your PSA blood test, your doctor may perform a digital rectal examination (DRE) to examine your prostate. Together, the PSA blood test and the DRE can suggest to your doctor if you need further testing.
If you have already been diagnosed with prostate cancer, a PSA blood test can be used to monitor the progress of your disease. This can indicate if you need surgery or other treatment, or if it is okay to simply wait. If a PSA velocity is done, this can suggest if you have an aggressive form of cancer.
A PSA blood test may also be used if you are undergoing treatment for prostate cancer. If treatment is effective, your PSA levels should decrease over time. Once you have finished the treatment for prostate cancer, your doctor may still recommend that you have PSA blood tests done, along with regular follow-up visits. An increase in your PSA level may indicate that cancer has recurred.
Together with the DRE, a PSA blood test may be used to screen for prostate cancer. Screening is a process wherein your doctor looks for a disease even if you have no symptoms. For some forms of cancer, regular screening is recommended after a certain age. This allows your doctor to detect diseases before serious problems can result.
Currently, however, a PSA blood test is not recommended for routine screening. Some doctors believe that a PSA blood test is best used only when you already have symptoms of prostate cancer. You should know all the benefits and disadvantages of prostate cancer screening, including having PSA blood tests, before you decide to undergo these procedures.
Why is a PSA blood test not part routine screening for men without symptoms?
A PSA blood test cannot definitively diagnose prostate cancer. It can only tell your doctor if prostate cancer is likely, and if additional tests are needed.
Prostate cancer can be a debilitating or even fatal disease. However, many cases of prostate cancer are not aggressive. Many men with prostate cancer have an indolent, or slow growing form of the disease. This form of prostate cancer causes few symptoms and has only a minimal impact on a man’s overall health. Even if you are diagnosed with prostate cancer, the disease may never cause any significant problems for you. Some studies show that early detection and treatment of prostate cancer improve your chances of surviving the disease; however, other studies are inconclusive.
Unfortunately, the procedures used to diagnose and treat prostate cancer have many side effects. You should be aware of these side effects and discuss the pros and cons of prostate cancer screening and diagnosis with your doctor. By getting all the facts, you can decide if getting a PSA blood test, along with other tests, will be more helpful to you, or if the risks of screening and diagnosis outweigh the benefits.
If your PSA blood test indicates that cancer is likely, your doctor may recommend a biopsy to confirm the diagnosis. However, undergoing a biopsy may cause excessive bleeding and infection. This may be more problematic for you than the symptoms of a slow growing prostate cancer.
Surgery and radiotherapy are treatments for prostate cancer. These procedures may cause problems such as being unable to control your urine, being unable to have or maintain an erection, being infertile, and other side effects.
You may to choose to undergo a PSA blood test, as well as other diagnostic procedures, in order to have definite knowledge about your health. It may relieve you to know whether or not you have cancer and to start treatment early.
You may also choose to wait before undergoing any screening tests or treatment procedures. The risks and side effects may not be worth it for you. You must discuss all your concerns with your doctor.