Two highly anticipated studies on using the Prostate Specific Antigen (PSA) blood test to screen for prostate cancer have been published in the last week. ^1,2 The studies have shown little benefit and much risk for the widely used screening test.  The picture for prostate cancer is clouded by the nature of the disease.  Studies of the prostate glands of men who have died of other diseases show that it is very common, even in younger men.  Biopsy of the prostate glands of men who have died of other causes show prostate cancer in 44% of men in their 50’s, and 83% in men 70 and older ³. Only a small number of these cancers were found during their lifetime. These men died of other causes. 

PSA screening results in finding more of these cancers. Today, we find prostate cancer in 1 of 6 American men.  Finding these cancers has not led to a decrease in deaths from prostate cancer, however.  It would seem that increased screening has led to treating cancers that would not kill the patient!

Nor is the anxiety of having a positive PSA test and biopsy a small matter.

I have had an intermittently high PSA levels for some time.   Last year I once again had a high value. I decided to repeat the test in eight weeks. I then understood my urologist’s comment that PSA stands for “Patient Stress and Anxiety”.  My active imagination, and my memories of my Uncle’s course with the prostate cancer made for much sleep loss, and a twenty pound weight loss (not all bad news, then!). My repeat PSA was also high, and a biopsy was done. The three days between the biopsy and my anxious call to the doctor’s office were indescribable. I do not fail to appreciate the irony of being on the other side of the biopsy needle.

Fortunately, the biopsy proved negative. Trust me, the most beautiful word in the English language is “benign”.

Had the biopsy shown prostate cancer, surgery would have had a serious chance of side-effects, with a high risk of sexual dysfunction (50%) or incontinence (up to 30%).⁴ Radiation therapy decreases the sexual dysfunction risk, but adds the possibility of bowel problems (persistent diarrhea, for example).

So should men be screened with the PSA test?  The advice now given is that the decision is an individual one that should be made by the patient and his doctor. Well, of course! In the real world, advice that doctors should discuss the PSA’s risks and benefits with patients is unrealistic.  Primary care physicians have about 11 minutes to perform an office visit.  Doctors do not have time to discuss the risks/benefits of PSA testing, and if they do so, it will be a “directed” discussion which will bias the information towards the doctor’s beliefs. 

Doctors tend to do more rather than less. How could it be otherwise? A surgeon believes that surgery is the best treatment for disease. If she didn’t, she would not have become a surgeon! As one of my textbooks said, “When all you have is a hammer, everything begins to look like a nail.” If a physician has a screening test, she may well be biased in favor of using it.
These are serious considerations, but Gina Kolata, one of the premier science reporters on the planet, has it just right when she quotes Dr. Peter B. Bach. If a man has a positive PSA that leads to a biopsy that shows prostate cancer, “there is a one in 50 chance that… (in ten years) , he will be spared death from a cancer that would otherwise have killed him. And there is a 49 in 50 chance that he will have been treated unnecessarily for a cancer that was never a threat to his life.”  

So is the glass 1/50 full, or 49/50 empty? The bet is yours to make, but I have had my last PSA screening test.