Johns Hopkins Health Alerts | Prostate Disorders | Your PSA Questions Answered

Is the free PSA a helpful diagnostic tool? When should a man have his first PSA test? Johns Hopkins urologist, Jacek L. Mostwin M.D. answers.

On the first PSA test:

Q. I am 56 years old and just had surgery for my prostate cancer (5.5 ng/ml, Gleason 6). Everything went fine. I amazed my doctor by going surfing less than a month after the surgery. My question, however, has to do with my son, who is now 30 years old. When should he have his first PSA test?
From a Prostate Bulletin subscriber in Santa Monica, CA

A. There are no universally accepted standards for these recommendations, although experts who have studied familial patterns of prostate cancer inheritance have recommended that members of primary affected relatives (brothers, fathers, sons) begin testing at age 40. The general recommendations of the American Urological Association are to begin PSA testing at age 50 for men in whom there is no family history, and to begin PSA testing at 40 for those with family histories.

We have on occasion seen sons of our patients come in with moderately advanced disease at age 40, so even this age is open to question. There is little harm in obtaining the first PSA as early as desired, then, assuming the value is no higher than the averages for that age group -- say, 0.6 ng/ml for a 35-year-old man -- follow the progress every few years. A gradual increase in PSA velocity suggests early development of the disease.

On the free PSA test:

Q. When you examine a patient, do you make use of free PSA in your diagnosis for prostate cancer, or do you go by PSA alone?
From a Prostate Bulletin subscriber in Bagnell, MO

A. Free PSA (or fPSA) can be a helpful aid in interpreting the significance of a PSA value between 4.0 and 10.0 ng/ml, the range in which 25% of men undergoing biopsy are found to have prostate cancer. In general, the free PSA is inversely proportional to the likelihood and the volume of prostate cancer in this group, but the value is not now commonly used in guiding clinical decisions. In an older man in whom a very large prostate is associated with a higher PSA value, a very high free PSA is more suggestive of benign growth, but the values are no longer used with as much conviction as they were only a few years ago.

Free PSA is being replaced by PSA velocity as a better indicator of the likelihood of a man’s harboring an undiagnosed prostate cancer. These super-refinements of PSA interpretations continue to change. There is little substitute for the prostate biopsy in determining the presence or absence of prostate cancer. However, once prostate biopsies have been done, changes in free PSA may help to guide management recommendations, such as for watchful waiting or repeat biopsies.

Johns Hopkins Health Alerts | Prostate Disorders | Your PSA Questions Answered