Crunching numbers can be frustrating when the numbers can’t be entirely trusted.
In the e-Alert “Postcard From Buenos Aires” (3/16/04), I told you how the prostate-specific antigen (PSA) test may be a useful tool for predicting the potential for prostate cancer, but only when combined with other types of screening for the disease.
In response, an HSI member named Peg wrote with this question: “On the subject of PSA, what are the levels? What is a low number and high number to really be concerned with? I hear the numbers and I really don’t know what they mean.”
This is a good question, because any man who has a PSA test will be able to discuss the results better with his doctor if he knows the simple parameters.
Here are the PSA ranges, as listed by the National Cancer Institute (NCI):
- Normal – 0 to 4 nanograms per milliliter (ng/ml)
- Slightly Elevated – 4 to 10 ng/ml
- Moderately Elevated – 10 to 20 ng/ml
- Highly Elevated – more than 20 ng/ml
According to NCI guidelines, PSA false positive results occur mostly in men who are 50 or older. In this age group, about 15 of every 100 men tested will have PSA levels in the slightly elevated range or higher. Of those 15, only three will actually have cancer.
Once again, it can’t be stressed strongly enough that a single elevated PSA reading should not prompt a biopsy without confirmation of cancer possibility from other screening methods.
To Your Good Health,
Health Sciences Institute
“Questions and Answers About the Prostate-Specific Antigen (PSA) Test” National Cancer Institute, cis.nci.nih.gov