Friday, December 23, 2011

U.S. Preventive Services Task Force recommendations of PSA screening for Prostate Cancer

How many of you read the following types of news article earlier this year?

Or this one,

I know a lot of my patients did and I’m disgusted.  The articles made statements such as;

The U.S. Preventive Services Task Force, which advises the government on health prevention measures, on Friday downgraded its recommendation on prostate cancer screening to a "D," which means it recommends against the service because "there is moderate or high certainty that the service has no net benefit or that the harms outweigh the benefits”


“Healthy men should no longer receive a P.S.A. blood test to screen for prostate cancer because the test does not save lives over all and often leads to more tests and treatments that needlessly cause pain, impotence and incontinence in many, a key government health panel has decided.”

Where do I start. As seems to be all so common with the mainstream media, they left out a few important facts from the recommendation from the USPSTF. It make for much more sensationalist articles. The grade’s came from the 2008 article. The newer 2011 article made no such recommendations. This newer article just stated that Prostate-specific antigen–based screening results in small or no reduction in prostate cancer–specific mortality and is associated with harms related to subsequent evaluation and treatments, some of which may be unnecessary.”

Let’s evaluate the 2008 recommendations, the first of which is;

The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of prostate cancer screening in men younger than age 75 years.

Let me paraphrase here, in men younger than 75 years old the current evidence is insufficient to assess the balance of benefits and harms of prostate cancer screening

The second recommendation was: 

The USPSTF recommends against screening for prostate cancer in men age 75 years or older.

Let’s deal with the second recommendation first. If you are 75 years old and are diagnosed with Prostate cancer there is a pretty good chance you are going to die of something else. This statement is statistically true, but I personally do not want to be treated as a statistic. Simply this means mean more than half of the people will die of something else. Maybe even 90%. But what if you are one of the men that won’t. Prostate cancer typically metastasizes to bone which can be very painful. Without diagnosis and treatment it’s can be a miserable death.

I personally think we need to be more intelligent with our evaluations. For example if we have two 75 year old patients;

  • ·      Patient A is diagnosed with prostate cancer with a PSA of 5000 and a Gleason Score of 4+5=9.
  • ·      Patient B has a PSA of 1.5 and Gleason is 3+3=6.

So in this case I would not recommend treatment for Patient B, I would repeat the PSA in 3-6 months and see how fast it’s progressing.

Patient A could benefit from local control of the prostate cancer, external beam Radiation treatment, then treatment of the any painful bone metastases.

Let’s confuse the issue, there is a third patient that has a PSA of 2.2 and a Gleason score of 4+5. He needs treatment.

Now back to the first recommendation, if you’re less than 75 years old then the data is insufficient. The USPSTF was comparing the validity of the PSA test. This is a subject that I will address in detail at a later date but it is my belief that the PSA test, although not perfect, is still currently the best test available. The report went on to say 12-13% of the PSA’s are falsely positive (we call it a false positive when a PSA test it considered positive due to it’s high value but is “proven” to be incorrect). Assuming this is true (again, I’ll address this issue later too), how do you prove it’s false. Normally the doctor will perform a Digital Rectal Exam (DRE) at the same time, this is used as secondary check (see link for more information). The more definitive test is a prostate biopsy. If the biopsy comes back negative then it’s assumed a false positive. I contend that, and I admit I have little proof other than my clinical experience, that 90% of these are bad or incorrect biopsy’s.

The newer report states that there is “no reduction in prostate cancer–specific mortality”. Assume that is true, that’s not the point, what about quality of life, would you rather die instantly of a massive stroke or heart attack or would you rather suffer with a painful debilitating disease eventually to succumb to the disease. I personally believe that early detection does increase life, the problem is when you dies and are known to have cancer, the doctor writes cancer on the death certificate. Less than 5% of people that die in a hospital ever get an autopsy. (this is the subject of a whole new blog).

The biggest problem I have with all this is in order to find out if you have an treatable form of prostate cancer you need to find it first. The best way is the PSA test. Does it have issues, yes, but the bigger issues are not the PSA test itself, but the biopsy and complications of treatment. The bottom line for most of our patients, is:

  • ·      Sure I don’t want erectile dysfunction, but I’d rather be alive.
  • ·      Sure I don’t want urinary incontinence, but I’d rather be alive.
  • ·      Sure I don’t want a rectal fistula, but I’d rather be alive.

So again, should you get a PSA screening, my answer is unequivocally, YES!

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