The prostate is a small gland about the size and shape of a walnut that sits below a man’s bladder just in front of the rectum. It is part of the male reproductive system. The prostate produces a protein called prostate-specific antigen (PSA). Small amounts of PSA can normally be found in the blood. A PSA test can be used to screen for problems with the prostate such as enlargement or cancer even before symptoms appear.
WHAT SHOULD I KNOW ABOUT PROSTATE CANCER?
Prostate cancer is the second most common cancer in men in the United States and is the second most common cause of death in males. Finding the cancer early can be important in getting the proper treatment. Prostate cancer usually grows slowly, and cell changes may begin many years before a tumor gets big enough to cause any symptoms. By age 50 years, very few men have symptoms of prostate cancer, yet some precancerous or cancerous cells may be present. More than half of all American men have some cancer in their prostate glands by the age of 80 years. Most of these cancers show no signs or symptoms and never become a serious threat to health. A small number of men are treated for prostate cancer. Most men with prostate cancer do not die from the disease. About 16% of American men are diagnosed with prostate cancer at some point in their lives. Of these individuals, 8% have serious symptoms and 3% die from the disease.
Risk factors for prostate cancer include age, race, family history, and diet. Patients who are 50 years of age or older have an increased risk for prostate cancer. African American men are at the highest risk of developing this type of cancer, followed by white men, Hispanic and Native American men, and Asian American men. The risk of prostate cancer is two to three times higher in men whose fathers or brothers have had the disease. Diets high in fat that contain few fruits and vegetables may also be associated with a higher risk of this type of cancer.
WHAT IS PSA TESTING?
Tissue of the prostate that is affected by cancer produces more PSA than healthy tissue, so a high level of PSA in the blood may mean that cancer is present. For this reason, the PSA test is mainly used to screen for prostate cancer. PSA levels are measured in terms of how many nanograms (ng) of PSA are present per milliliter (mL) in your blood. If your PSA level is 4 ng/mL or higher, your health care team will have you undergo more testing to evaluate you for prostate cancer.
The American Urological Association suggests that men should have a baseline test (a test that measures your current or pretreatment levels) of their PSA level completed at age 40 years. You will complete the PSA test again every so often to see how your PSA level may or may not have changed. The results of your baseline PSA test and how your levels change over time will determine how often this testing should take place as well as when and if more follow-up is needed.
A high level of PSA in the blood may also mean that the prostate is enlarged or inflamed. Because a high PSA level can be seen with medical conditions other than cancer, it is important for a digital rectal examination to be done along with the blood test. During this test, your health care provider will insert a lubricated, gloved finger into your rectum in order to feel the prostate. This test will help determine whether your prostate is enlarged, has abnormal lumps, or is tender. If abnormal results are present from the PSA blood test and/or the digital rectal examination, your health care provider will order a prostate biopsy. During the prostate biopsy, samples of tissue from the prostate will be removed and sent for microscopic examination. A prostate biopsy can determine with certainty whether you have prostate cancer.
WHAT ARE THE RISKS?
Some studies have found that PSA screening is an effective way to screen men for prostate cancer. However, others have found that too much screening leads to overtesting and treatment that might not be necessary, such as too many biopsies. Certain studies show that PSA testing can only reduce deaths from prostate cancer by about 20%. In May 2012, the U.S. Preventive Services Task Force issued a statement that men of all ages should no longer undergo PSA screening beause of the small potential benefit and many risks, such as blood clot, heart attack, stroke, or even death.
THE BOTTOM LINE
PSA testing can help your health care provider diagnose prostate cancer early, which has been proven to lead to better treatment and more positive outcomes. However, the risks may outweigh the benefits, and the decision to have PSA testing done should be made on an individual basis with your care team. JAAPA
This article originally appeared on JAAPA