Spawning an Industry for Drugs and Diapers
Dr. Ablin: Third, we can't tell the difference between latent cancer or nonclinical cancer and aggressive cancer. I make the analogy in the book of a rabbit and a turtle and an open box. The turtle crawls around the box and goes nowhere. That's the nonaggressive, indolent cancer. The rabbit, representing the aggressive cancer, can jump out of the box and metastasize anytime. The problem is, we can't tell the difference between a rabbit and a turtle.
The most important crux is that prostate cancer is an age-related disease. If you get, for example, 100 men -- black or white -- between the ages of 60 and 69 years and do biopsies, you will find that 65% of these men have prostate cancer because it's age-related.
Dr. Topol: But rarely is it aggressive. In the future, is it possible that we will identify a marker that will help sort out whether someone has an aggressive type of prostate cancer that warrants the big-gun treatments?
Dr. Ablin: Going back to when I started working on this in 1967, up to the present time, no one has found a cancer-specific antigen for the prostate. As we talk today, there are 11 -- and probably more -- tests out there that have been proposed as a replacement for the PSA. These tests are awaiting validation and clinical trials. I have reviewed these tests. So far, it's questionable as to whether any of them right now will fulfill what we are looking for.
Dr. Topol: They are not likely, at least imminently, to get us out of this bind of not being able to partition the serious types of prostate cancer from the innocent types. Is that right?
Dr. Ablin: One problem is that people are still using the PSA test. They go from PSA, to ultrasonography, to biopsy. It's a cash cow.
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Cite this: PSA Test Is Misused, Unreliable, Says the Antigen's Discoverer - Medscape - Aug 08, 2014.
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