Wasted air in the media and the merits of PSA testing

So for those who simply can’t leave this subject alone, there was a pointless “debate” in today’s Wall Street Journal about the merits of regular PSA testing between Richard Ablin, PhD and Oliver Sartor, MD.

The fundamental problem is that this issue is not a simple yes/no, black/white, right/wrong discussion. The value of the PSA test and the frequency with which it should be given depends not just on the test, but on the individual risk level and the individual mindset of the man to whom the test is potentially going to be given.

The other problem is that Dr. Ablin’s claim to have “discovered” the PSA test is (at best) highly debatable … even if he was the first person to isolate the protein now known as the prostate-specific antigen.

5 Responses

  1. Is this claim reasonably true:

    “DR. SARTOR: Since PSA screening became routine in the 1990s, prostate cancer mortality rates have declined by nearly 40%.”

    A Cochrane Review at least raises questions about the reasonableness of this claim.

    This review identified five relevant studies, comprising 341,351 participants in total. Two of the studies were assessed to be of low risk of bias, whilst the remaining three had methodological weaknesses. Meta-analysis of the five included studies demonstrated no statistically significant reduction in prostate cancer-specific mortality (RR 0.95, 95% CI 0.85 to 1.07). Only a preplanned analysis of a “core” age group of men from the largest study included in this review reported a significant 20% relative reduction in prostate cancer-specific mortality. Among this “core” group of men aged 55 to 69 the ERSPC authors report that 1,410 men would need to be screened to prevent one additional death from prostate cancer during a 9-year period, which is also associated with 48 men needing to be treated for prostate cancer (RR 0.80, 95% CI 0.65 to 0.98).

  2. Dear Dave C:

    You are comparing apples to oranges. Dr. Sartor’s point, which is completely accurate, is that since the PSA test became available the rate of prostate cancer mortality in the USA has dropped by 40%. However, Dr. Sartor is not necessarily implying that this is entirely due to the availability of the PSA test. He is simply stating that there is a correlation between the two pieces of information, and no one has ever denied this.

    By contrast, whether mass, population-based, annual PSA testing actually lowers prostate cancer mortality on its own is a very different question that people have attempted to evaluate in clinical trials, with the results described in the Cochrane review.

    These are two very different types of data and you need to be careful to appreciate the distinction. There is no doubt in my mind that the availability of the PSA test has affected the risk for prostate cancer-specific mortality … but I am doubtful that it has done this on its own. Access to the PSA test has been followed by some pretty major advances in the management of prostate cancer too.

  3. Do you know any online references for US prostate cancer mortality trends?

  4. Dear Dave:

    Here is a link to the simple SEER fact sheet. There is a vast amount of more detailed data available on the SEER web site, but you do need to understand that the way these data have been collected and analyzed has changed significantly over time.

  5. … the way these data have been collected and analyzed has changed significantly over time.

    Indeed, as has the definition of prostate cancer diagnosed by way of a needle biopsy.

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