Health Alert 262
A new study published in The New England Journal of Medicine shows that no PSA level can be considered “normal” and completely free of the risk of having prostate cancer.1
The Prostate Specific Antigen (PSA) test has been the primary prostate cancer screening tool for about 15 years. A PSA of less than 4 ng/ml was considered safe. The idea that a PSA level of 4 ng/ml should be the upper limit of normal comes from a study done 10 years ago. The problem with this conclusion is now coming to light. This new research found that even with a PSA level of zero, you could still have prostate cancer.
The findings of this latest study show that even if you have a PSA level below 4, you still may have prostate cancer. In fact, this research shows that no PSA level, even a level of zero, is completely risk free. Of the 2,950 men who had an end-of-study biopsy, 449 or 15.2% were found to have prostate cancer.2 The following chart shows the prevalence of prostate cancer with the corresponding PSA level:
|6.6%||0 to 0.5|
|10.1%||0.6 to 1|
|17%||1.1 to 2|
|23.9%||2.1 to 3|
|26.9%||3.1 to 4|
This chart shows that of men in the study who had prostate cancer, 84.5% of them had a PSA level of 4 or less. That’s well over ¾ of them. But that’s not the only one…
Not only did this study find prostate cancer in men with low PSA levels, but it also found the tumors were relatively serious. Fast growing and more serious cancers, were found in only 2.3% of patients. But those cancers were found at every PSA level.
I recommend if you are over 50, have a PSA test done every year. But by the age of 65, PSA is not as good of an indicator. Because by then, you probably will have BPH-which is the most common diagnosis in men over 55. Your family history is a more valuable indicator for the risk of prostate cancer. Did your father or brother have prostate cancer? If you can answer yes to this and you have a higher PSA, then possibly you should consider a biopsy.
Most importantly though, you should watch your PSA Velocity. PSA velocity is the measurement of how your PSA levels rise over time.
We need at least 3 PSA measurements to get an accurate PSA Velocity. Your PSA measurements should each be between 6 months and 2 years apart. A normal PSA velocity is less than 0.75 ng/ml/yr. Any higher is an indication of an increased risk of prostate cancer.
To Your Good Health,
Al Sears MD
1. Thompson, IM, MD, Paules, DK, PhD., et. al., “Prevalence of Prostate Cancer among Men with a Prostate-Specific Antigen Level < 4.0 ng per Milliliter”; The New England Journal of Medicine, May 27, 2004, vol 350: 2239
2. Thompson, IM, MD, Goodman, PJ, MS, et. al., “The Influence of Finasteride on the Development of Prostate Cancer,” The New England Journal of Medicine, July 17, 2003; vol 349: 215