Wednesday, March 14, 2012

PSA Debate Continues

We all remember the discussion that the Government declared PSA tests as not effective. It was the same group which wanted to do away with mammograms. Most likely the same group which wants to do away with health care for anyone over 65, the current team in Washington that is.

Well NEJM just reported a different tale.

Here it is:

Namely it does save lives! Eureka, that is what we have been saying for the past four years, and now we have the data in spades.

Here is the test:

The principal screening test was measurement of the serum PSA level with the use of the Tandem-R/Tandem-E/Access assay (Hybritech). A positive test result, defined as a PSA value of 3.0 ng per milliliter or higher, was an indication for biopsy in most centers. Sextant prostatic biopsies were recommended for all men with positive test results; lateralized sextant biopsies were adopted in June 1996. Some exceptions to these procedures have been described previously.

 Yes a PSA cutoff of 3.0, not 4.0, and sextant biopsies. Today we would use 14 cores at a minimum, and saturation in many cases, say 24 cores, although it increases morbidity to a degree.

The end point was:

The primary end point of the trial was prostate-cancer mortality. We evaluated deaths among men in both the screening group and the control group in whom prostate cancer was diagnosed (including cases that were first diagnosed at autopsy), regardless of the official cause of death, as described previously. Data on overall mortality were collected by linkage to the national registries. Each trial center followed the common core protocol and provided key data to the joint independent data center every 6 months. The independent data monitoring committee received updates every 6 months according to a predefined monitoring and evaluation plan.

They conclude:

The controversy regarding screening for prostate cancer has been renewed by the publication of the draft report of the U.S. Preventive Services Task Force, which after a literature-based analysis of benefits and harms recommended against the use of PSA testing in asymptomatic men. The report has been discussed in several Perspective articles in the Journal. Clearly, the issue can be resolved only on the basis of evidence that considers both the advantages and disadvantages of screening, data that are not available at this time. Our study shows that the absolute effect of screening on the risk of death from prostate cancer increased in the intention-to-screen analysis from 0.71 to 1.07 deaths per 1000 men at a median of 11 years of follow-up, as compared with the initial results with a shorter follow-up period.

Clearly there is a benefit but clearly as I have previously stated they did not ask the correct question, which is:

"What should the PSA level be by age, race etc so as to have a decrease in survivability by some factor x?"

Notwithstanding, there is a clear benefit.  The details of the benefit are yet to be determined but the conclusion is that the USPSTF conclusion is in error. The "Death Panel"'s conclusion is just that. And we have just begun!