The prostate-specific antigen (PSA) test is a part of the testing package recommended for detecting prostate cancer. The test is useful because it can detect the possibility of cancer before any symptoms develop, but it is not a diagnostic test. Doctors use the results of the PSA test as well as the digital rectal examination to determine if there is any reason to perform a biopsy, which is necessary to determine if the prostate contains malignant cells.
Traditional PSA Results
A traditional PSA test measures the levels of prostate-specific antigen in the blood. PSA results return as the number of nanograms of PSA present in each milliliter of blood (ng/mL). If the test comes back with a result of 4.0 ng/mL or higher, most doctors will want to perform additional testing.
Cancerous cells in the prostate cause the gland to produce more prostate-specific antigen, which is the reason that high levels are associated with prostate cancer. Other reasons that a PSA test can come back with high levels include inflammation of the prostate or enlargement of the gland. Both of these conditions are relatively common in older men but, while they require treatment, are no cause for alarm.
Alternative Tests
Many doctors are working to refine PSA testing so that it is a more reliable indicator of malignant cells. Regardless of how many times a man hears that a high PSA test can be the result of a wide range of ailments, the testing and waiting for follow-ups is extremely stressful. High PSA test results also lead to many unnecessary biopsies. Earlier detection means a better prognosis, but the process of additional testing and biopsies results in unnecessary worry and medical expense.
Some doctors are recommending a PSA velocity test, which measures changes in the PSA levels over a specific period. A rapid change in PSA levels is often more indicative of a fast developing health condition than high levels that remain stable. Other doctors are looking at PSA levels as only one part of a whole. PSA levels naturally increase as a man ages, so the doctor who sees a high PSA level in a 30-year-old will be more inclined to recommend further testing than when he sees high PSA levels in a 75-year-old. Finally, some doctors are looking at the levels of free PSA in the blood. Someone with high PSA levels but a low level of free PSA is more inclined to have a malignant tumor than someone with high PSA levels and high levels of free PSA.
What You Need to Know
Regardless of whether or not your doctor uses the traditional PSA test or one of the newer, modified versions, it is important to know what the results are and how the doctor is interpreting them. A PSA result of 4.0 ng/mL or greater is a cause for concern. If your doctor has not conducted a digital rectal exam yet, he should if the PSA results come back high. If he takes a wait-and-see approach, ask to come in and have your PSA levels retested in a month or two. Even if the doctor does not normally conduct PSA velocity tests, having a retest can ease your mind or tell you and your doctor if there is a reason to schedule a biopsy.
