Sunday, February 27, 2011

PSA and the Press

Another example of how the Press gets things wrong. The JNCI paper we discussed before states:

Biopsying men with high PSA velocity but no other indication would lead to a large number of additional biopsies, with close to one in seven men being biopsied...We found no evidence to support the recommendation that men with high PSA velocity should be biopsied in the absence of other indications; this measure should not be included in practice guidelines. 

 Read this very carefully. Despite all the prior studies that are to the contrary, they state PSA velocity should not be the sole factor, specifically they state high PSA velocity but no other indication. Not that PSA velocity has no value at all. It is a conditional statement, so what are the conditions?

But the NY Times states:

The researchers, writing in the March 16 issue of The Journal of the National Cancer Institute, concluded that using P.S.A. velocity for prostate cancer detection is ineffective, that it leads to unnecessary biopsies and that references to it should be removed from professional guidelines and policy statements. 

The Times continues:

Similarly, it is easy to demonstrate a statistical relationship between sharp rises in P.S.A. and cancer, but the correlation reveals no more information than is already available with a P.S.A. reading, a digital examination and a family history. It is irrelevant in deciding whether a biopsy is needed. 

Not really folks!  We had demonstrated on the basis of physiological, cellular and clinical data that one needs to track PSA over a long period. Looking at change is the concern. Chang and rate of change are frankly the same! I know the concept is quite difficult for reporters, it is after all High School physics at best, but alas we are talking about a reporter, not even a High School Teacher, you know those folks who could not even major in education and went into communications or journalism.

The final quote is:

But at this point, he is firmly against biopsies on the basis of velocity alone. “If your P.S.A. is in the normal range, you shouldn’t get a biopsy,” he said. “Changes or spikes in P.S.A. are not something to worry about if your P.S.A. is still normal.” 

But wait a moment, what if you have 2 first degree relatives with an aggressive  form of prostate cancer and who died in two years or less after diagnosis? Perhaps family history should play a part. Ya think!

Or is all of this a way to implement the comparative clinical effectiveness in the new health care law which means that by the time it is diagnosed your are dead, at least clinically!