New Prostate Cancer Test: A Major Advance?

April 28, 2007 — -- An article in the current issue of the journal Urology illustrates some of the hopes and barriers related to advancing our abilities to diagnose prostate cancer accurately through screening tests at the earliest possible time.

This particular article reports information about a prostate cancer protein found in the blood called EPCA-2.

The research, performed at Johns Hopkins in Baltimore -- recognized as one of the leading prostate cancer treatment and research centers in the world -- demonstrates that this new marker appears to be more sensitive and specific in detecting prostate cancer compared to the widely used PSA test.

But the question remains whether or not this is a major advance in the screening and diagnosis of prostate cancer.

The problem with the PSA test, which the article notes has been around and widely used for more than 25 years, is that, although it does detect prostate cancer through a fairly simple and routine blood test, it nonetheless is not particularly specific to prostate cancer.

That means that it frequently picks up other prostate conditions such as benign, or noncancerous, enlargement of the gland.

Another issue with the PSA test is what is normal and what is abnormal in terms of the PSA level in the blood.

We used to say that a PSA value on the blood test that was less than four was OK. More recent research suggests that even lower levels can be associated with prostate cancer.

When determining a "normal" PSA, the doctor should be considering the age of the patient and the change in the PSA value over time.

What that means is that if a young man (for this discussion, that would be someone in their 40s or early 50s) has a PSA of two, that may be abnormal, while a PSA slightly more than four in an 80-year-old man may not be of much concern.

It would be great if we had another simple test that helped solve some of these problems and allowed us to focus on those men who actually have prostate cancer as opposed to doing further investigations and evaluations on many men who don't have prostate cancer.