Lee Jackson MD
Medical Advisory Board
INTERPRETING AN ELEVATED PSA
Elevated PSA levels must be interpreted thoughtfully and with care. There is not a level of PSA that is specifically diagnostic of prostate cancer. To use PSA in order to estimate a man’s risk of prostate cancer, PSA should be interpreted over time and in the context of other risk factors; such as a strong family history of prostate cancer and African-American ethnicity.
If your physician has determined the PSA value to be elevated, it should then first be repeated again in a few weeks. A course of antibiotics may be recommended during this time, but is not indicated or helpful in the absence of urinary symptoms.
If the repeat PSA is persistently elevated, then further evaluation and interpretation is required. This also considers the size and consistency of the prostate at digital rectal exam, as well as, the presence or absence of a family history of prostate cancer and the patient’s ethnicity.
If more information is needed to better characterize one’s risk for prostate cancer, additional testing can be done. This may include the following: measuring the percent free PSA, PCA-3 urinary protein levels and multi-parametric MRI imaging of the prostate.
Percent free PSA measures the portion of PSA circulating in the bloodstream free of other proteins. PSA circulates either bound to other proteins or free of other proteins. If the portion of PSA circulating free of other proteins is low, this indicates a higher risk of prostate cancer, suggesting the need for further investigation.
PCA-3 is a protein commonly associated with prostate cancer and is measured in the urine. High levels of PCA-3 indicate a significant risk of prostate cancer and will need to be investigated.
Recently, a specialized MRI of the prostate has shown promise in identifying clinically significant prostate cancer and may be useful in the interpretation of elevated PSA levels.
In Summary: If multiple PSA levels are persistently elevated in the presence of other risk factors or associated with low percentages of free PSA or high levels of urinary PCA-3 proteins, then the risk of a clinically significant prostate cancer is high enough to justify pursuing a prostate biopsy.