Monday, March 8, 2010

Prostate, Prostate CA, BPH, and economics

There has been much written in the news lately about the prostate: prostate cancer, new guidelines for Dx. and Rx., robotic prostate surgery, and a recent article in Archives of Internal Medicine (vol 170, #5, 3/8/10, pp 451-452)by Dr. M. Barry.

Just as an aside, "regular" prostate surgery is generally done in less than 2 hours, and robotic surgery generally takes longer than 3 hours. If you undergo more than 2.5 hours Operating room time,the risk of complications rises sharply.

What it all boils down to is that THERE IS NO INCONTROVERTIBLE EVIDENCE THAT TREATING PROSTATE CANCER SAVES LIVES.This does not mean that every male with prostate cancer will die from the cancer, but only that no treatment has been shown to cure it. The only study that has not been done is to do quadrant biopsies on all males annually, beginning at age 40, and treating all cancers with a Gleason score of 3 or less. Once prostate cancer is diagnosed (prompted by a rectal exam or an elevated PSA) surveys have shown that your family doctor will often recommend watchful waiting, your urologist will most likely recommend surgery, and a radiation oncologist will most likely recommend radiation. Since there is no evidence that treatment saves lives, it is difficult to justify an annual PSA test, unless the patient agrees to treatment. And, based upon my office experience, his wife will never agree to watchful waiting, so send the lab results to his office.

Once the CA is treated, many men have a few months of urinary incontinence, and/or erectile dysfunction. This may last for 2 years, or be permanent. If the ED seems to be permanent, the most satisfying treatment seems to be to transplant the 12th rib to the center of the penis, so that the "erection" is permanent.

Since the prostate grows without limit, all men will eventually have symptoms of BPH, evidenced by having to get up at night to urinate, or reduction in urinary stream force,etc. The prescribed treatment is with selective alpha-blockers, and/or reductase inhibitors (Proscar, etc.)The newest selective alpha-blocker, which has the least effect on the ciliary artery and therefore is the safest vis-a-vis future cataract surgery, is Rapaflo, (silodosin) 4mg or 8mg at bedtime. Only the combination of a reductase inhibitor plus an alpha-blocker has been shown to reduce the future need for a TURP to open up the prostatic urethra. However, since the old TURP involved inserting a rotatable knife thru the penis and up to the prostate, much like a Roto-rooter operation, and the procedure is now relatively bloodless and pain-free when done with the "green light" laser, not all men opt for the two drugs, especially since Proscar and its relatives diminish the amount of seminal fluid that is ejaculated. One should also remember that alpha blockers can increase the amount of retrograde ejaculation, i.e. backwards into the bladder, rather than forward and out of the urethra.

As for economics, why do you think surgeons recommend surgery and radiators recommend radiation? This leads into the larger question of economics. It is somewhat paradoxical that in today's times, microeconomics would suggest that you save your money, while macroeconomics wants you to help America spend its way out of the recession.

As a former mathematical and experimental physicist, I have looked into the mathematics, models and predictions of all branches of economics, and they all have the same fallacy: They assume that humans are always rational, and never panic sell or binge buy. This is clearly not the case (cf. "The Madness of Crowds"), but since arbitrary,"irrational" behavior cannot be mathematically modeled, calculated or predicted, it is excluded from ALL economic mathematics and their models. When the Black-Scholes "Theorem" was used to model the portfolio of Long Term Capital Funding, it was implicit in their model that no major country would fail to support its own currency. No allowance was made for this occurrence because (a) its happening was abrupt and unpredictable, and (b) the results depended on which country forfeited its currency. Therefore, when Russia defaulted on the ruble, LTCF would have gone bankrupt to the tune of $4B, but the U.S. Gov't bailed them out.

I won't even go into the required nonlinearity of any market model,that is caused by feedback. What we are dealing with here is the drunkard looking under the lamppost for his lost auto keys because the light is better there, rather than in the dark up the block where he actually dropped them. (And no, I lost no money in the market plunge.) People feel more comfortable with a "prediction" created by mathematics, even though GIGO is operating on a huge scale. Now in physics, if the result of an experiment differs from that predicted by our model of the world, we change our model. But economists cannot change their models, because catastrophe theory is too difficult to be mathematically tractable enough to use for predictions (see Rene Thom's work on this problem).

There are and seemingly will always be market crashes, because it is impossible to predict their occurrence or their nature (?something similar to earthquake prediction). No matter what the model, it basically assumes that the past can be used to model the future. How a tulip bulb crash can model Penn Central or the crash of 1873 is not clear to me. It is the question of predicting individual economic behavior vs. mass economic behavior. We have the same problem in medicine. I have no problem recommending that 1,000,000 women have annual mammograms beginning at age ??, but I have 25 female patients over the age of 85 who have never had mammograms or breast cancer, and so far they are right, too.