So we might as well acknowledge that the New Year is going to continue where the old year left off when it comes to the issue of testing (“screening”) men for risk of prostate cancer.
Near the end of 2011, Vickers and Lilja published an article in the World Journal of Urology suggesting the following strategic approach to assessment of prostate cancer risk and the potential need for treatment:
- Family history and known genomic markers are not of sufficient accuracy on their own to project risk in a practical manner.
- Serum PSA levels are strongly prognostic of the long-term risk of aggressive prostate cancer.
- For men < 50 years of age with PSA levels of ~1.5 ng/ml or higher there is high risk and intensive monitoring is appropriate.
- For men of 45 to 6o years of age
- Intervals between PSA tests can be based on prior PSA levels.
- A 2- to 4-year retesting interval seems appropriate for men with PSA levels of 1 ng/ml or higher.
- Tests every 6 to 8 years seem appropriate for men with PSA levels < 1 ng/ml.
- Continued testing of men aged 60 or older with PSA levels of less than 1 or 2 ng/ml is difficult to justify.
And then there were four more commentaries in the December 28th edition of the Journal of the American Medical Association (JAMA).
- “Prostate cancer screening — the evidence, the recommendations, and the clinical implications,” by Chou and LeFevre
- “Missing the mark on prostate-specific antigen screening,” by Miller and Hollenbeck
- “Prostate cancer screening — time to abandon one-size-fits-all approach,” by Kim and Davis
- “Making the call” by Welch
Unfortunately the full texts of these four opinion pieces are only available to subscribers to JAMA, which is a pity. However, a summary of these articles is available on the Medscape web site.
Of the four, the one by Kim and Davis makes the most sense to us. Like Lilja and Vickers, they are effectively suggesting that it is time to stop bashing a square peg into a round hole. Using annual PSA tests without careful thought to try to decide who to biopsy hasn’t been working well for most of the past 20 years. Until we have tests that can really project individual risk with accuracy based on much better testing instruments, it is time to take PSA data in concert with other data from “the whole man” to make individualized “best case” and “worst case” scenario decisions about who really needs to get biopsied.
It is also high time that we recognized that there are some types of aggressive prostate cancer that we just can’t treat well at this time, and these are the cancers that cause many of the 30,000 or so deaths in America each year. While we lump all prostate cancers together and then try to justify annual, mass, population-based screening as a means to eliminate this disorder entirely, we are missing the entire point that some pathologically identifiable cancers (maybe 20 percent of all prostate cancers) simply don’t need treatment at all. We are also missing the point that PSA testing is never going to be best way to identify the highly aggressive forms of prostate cancer that are most likely to kill men. By the time we identify most of those cancers today, they have already micro-metastasized (although that may not be immediately evident).