High PSA Level? Check it Again
PSA Tests Can Produce False Positives; Repeat Test After Six Weeks Advised
The PSA blood test, first introduced in the U.S. in 1986, is still a controversial test for prostate cancer. Even though a PSA test is likely to detect prostate cancer at an earlier stage, there is no evidence that the test saves lives. This is because prostate cancer is generally slow-growing and typically strikes men at an older age, when they are more likely to die from other causes. Thus, treating prostate cancer in some men, the argument goes, may cause more harm than benefit.
"Men don't realize the downside to a PSA test," Evelyn C. Y. Chan, MD, of the University of Texas-Houston Medical School, tells WebMD. "There are false positives associated with this test, and there are false negatives. And it has never been established that the PSA test is going to reduce deaths caused by prostate cancer."
A high PSA level indicates some abnormality in the prostate -- possibly cancer, but also any type of prostate infection or prostate enlargement, which occurs in most men after age 50. Even ejaculation within two days of having a PSA test may result in artificially high levels suggesting a "false positive."
"My suggestion for men considering the test is that they ask their doctor whether or not a PSA is the right test for them -- and then ask their doctors why," Chan tells WebMD. "Don't feel that this is a test that everyone agrees upon and recommends."
The American Urological Association, the American Cancer Society, and the American College of Physicians recommend that doctors discuss PSA and other screening tests each year with men older than age 50, high-risk men, black men, or those with a family history of prostate cancer, should talk to their doctor at age 40.
Meanwhile, the U.S. Preventive Services Task Force and the National Cancer Institute are opposed to routine PSA screening, believing the risks of follow-up tests and the side effects of treatment may outweigh the possible benefits for many men.
"I believe the PSA test saves lives," Eastham tells WebMD. "But there are many factors that influence PSA levels, so the test needs to be used with confirming evidence before undue worry or undue procedures."