To the credit of the authors of the current report, they have made it very clear in their article that this is simply a preliminary report of a newly discovered protein-based test. They commented that the test itself was "tested" on highly selected patients and was not evaluated in a typical setting where the doctor is actually screening a man for prostate cancer.
Establishing the value of this test, therefore, must be done in the context in which the test is going to be used.
That will mean many men who do not have prostate cancer will have the new test done side by side with the standard PSA test. Then, the researchers will look at the outcomes of both tests and compare them to each other.
If the new test turns out to be more accurate than PSA, then it will be a major advance. But we must always bear in mind that it may not show value in the subsequent "real life" evaluation.
The fact is we simply don't know today, based on this initial report, whether or not this test is going to be better, as good as or even worse than PSA testing when it is put into a clinical trial.
Trying to find cancer through a blood test has been an area of research interest for many years. We have actually had other tests besides the PSA test that have been used in monitoring cancer patients for some time.
So, the EPCA test reported here is new, but it is not alone. Many researchers seek protein markers in the blood that may lead us to screen and diagnose cancer at the earliest possible moment.
I have heard experts say that within the next decade, we will have methods available that will incorporate nanotechnology and will allow us to take a drop of blood, put it on a chip, send it to the lab, and diagnose disease long before a doctor could find evidence of that disease by more standard clinical tests.
Other experts have reported research where they can monitor levels of a cancer-related protein called VEGF in rats, and pretreat those animals before a cancer tumor can be clinically detected.
So, to me, what this new report represents is an exciting opportunity that may affect medical care in the future.
If the clinical research, which will undoubtedly follow this report produces positive results, it will certainly help us direct our attention to men who have a greater likelihood of having prostate cancer, instead of the more nonspecific approaches we have today with the less sophisticated PSA test.
But we can't diminish the value of the PSA test in apparently helping to reduce deaths from prostate cancer, and we still need to prove that the new test is actually better than the older PSA test.
So, as with so many other exciting developments I have discussed in this blog, we still have a way to go to really understand how much impact this new test will actually have on the diagnosis of men with prostate cancer.
We are simply not there yet.
Dr. Len Lichtenfeld is deputy chief medical officer for the American Cancer Society. You can view the full blog by clicking here.