Prostate cancer
screening: Should you get a PSA test?
By Mayo Clinic staff - November 9, 2012 <http://www.mayoclinic.com/health/prostate-cancer/HQ01273/> Summary: Making the decision to have a PSA test depends on a variety of factors. Here are some tips that can help you make a good decision. Cancer screening tests — including the prostate-specific antigen (PSA) test to look for signs of prostate cancer — can be a good idea. Prostate cancer screening can help identify cancer early on, when treatment is most effective. And a normal PSA test, combined with a digital rectal exam, can help reassure you that it's unlikely you have prostate cancer. But getting a PSA test for prostate cancer may not be necessary for some men, especially men 75 and older. Professional organizations vary in their recommendations about who should — and who shouldn't — get a PSA screening test. While some have definitive guidelines, others leave the decision up to men and their doctors. Organizations that do recommend PSA screening generally encourage the test in men between the ages of 40 and 75, and in men with an increased risk of prostate cancer. Ultimately, whether you have a PSA test is something you should decide after discussing it with your doctor, considering your risk factors and weighing your personal preferences. Here's more information to help you prepare for a conversation with your doctor about PSA testing. Simple test, not-so-simple decisionThere are a number of pros and cons to the PSA test.
What is PSA?Prostate-specific antigen (PSA) is a protein produced by both cancerous (malignant) and noncancerous (benign) prostate tissue. PSA helps liquefy the semen. A small amount of PSA normally enters the bloodstream. Prostate cancer cells usually make more PSA than do benign cells, causing PSA levels in your blood to rise. But PSA levels can also be elevated in men with enlarged or inflamed prostate glands. Therefore, determining what a high PSA score means can be complicated. Besides the PSA number itself, your doctor will consider a number of other factors to evaluate your PSA scores:
When elevated PSA isn't cancerWhile high PSA levels can be a sign of prostate cancer, a number of conditions other than prostate cancer can cause PSA levels to rise. These other conditions could cause what's known as a "false-positive" — meaning a result that falsely indicates you might have prostate cancer when you don't. Conditions that could lead to an elevated PSA level in men who don't have prostate cancer include:
False-positives are common. Only about 1 in 4 men with a positive PSA test turns out to have prostate cancer. When prostate cancer doesn't increase PSASome prostate cancers, particularly those that grow quickly, may not produce much PSA. In this case, you might have what's known as a "false-negative" — a test result that incorrectly indicates you don't have prostate cancer when you do. Because of the complexity of these relating factors, it's important to have a doctor who is experienced in interpreting PSA levels evaluate your situation. What's the advantage of a PSA test?Detecting certain types of prostate cancer early can be critical. Elevated PSA results may reveal prostate cancer that's likely to spread to other parts of your body (metastasize), or they may reveal a quick-growing cancer that's likely to cause other problems. Early treatment can help catch the cancer before it
becomes life-threatening or causes serious symptoms. In
some cases, identifying cancer early means you will need
less aggressive treatment — thus reducing your risk of
certain side effects, such as erectile dysfunction and
incontinence. What's risky about a PSA test?You may wonder how getting a test for prostate cancer could have a downside. After all, there's little risk involved in the test itself — it requires simply drawing blood for evaluation in a lab. However, there are some potential dangers once the results are in. These include:
Digital rectal examinationThe PSA test isn't the only screening tool for prostate cancer. Digital rectal examination (DRE) is another important way to evaluate the prostate and look for signs of cancer. Your doctor performs the test by inserting a gloved, lubricated finger into your rectum to feel the prostate for bumps or other abnormalities. It's a quick, safe and easy test. In addition to checking for signs of prostate cancer, your doctor can use a DRE to check for signs of rectal cancer. A DRE should always be done with a PSA test when screening for prostate cancer. This will help minimize the risk of missing prostate cancer — or wrongly identifying a benign prostate abnormality as cancer. Think about your risk factors for prostate cancerKnowing the risk factors for prostate cancer can help you determine if and when you want to begin prostate cancer screening. The main risk factors include:
Consider the varying viewpoints: What are the recommendations?
How does it add up? A positive PSA test can be a lifesaver for some men,
identifying prostate cancer that needs treatment early.
It's generally a good idea to have PSA testing done if
you're at increased risk of prostate cancer. However, not
all men need to have the screening. You may want to think
twice if you're in a group of men unlikely to benefit from
it. After considering the pros and cons of screening, your
age, general health and risk factors, your preferences and
what the experts say, talk to your doctor. Together you
can make the right decision for you. Copyright © 1998-2012 Mayo Foundation
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