Map of life expectancy at birth from Global Education Project.

Tuesday, May 22, 2007

A dissent worth pondering

ABC News sends me all their health-related stories, which makes me feel important but I assume their blogger mailing list has a couple of hundred thousand entries.

Anyway, it usually results in a quick click on the delete button, especially when ignorant blowhard and pathological liar John Stossel is involved. Stossel has been caught repeatedly in flagrant lies and journalistic fraud, including by me, which I'm sure rattled the teacups in the ABC boardroom. So how does he still draw a paycheck and get access to the public airwaves, you ask? Too easy for a hint. ABC needs a conservative voice in health and consumer affairs, but it is impossible to simultaneously argue for conservative positions and tell the truth. Ergo, ABC must sacrifice any requirement for truth in reporting in the much higher interest of balance.

That said, a piece came across my virtual desk today that you might want to read. I've written about screening mammography before, but nobody cares what I think. However, Nortin Hadler, M.D., who feels about the same way I do, shares access to the grand stage with the liars and fools who usually dominate, and he says what needs to be said clearly enough. Screening mammography has a very specific meaning: it means that women with no known symptoms or signs of breast cancer, and no known elevated risk factors, are encouraged to undergo mammography every year or every two years, depending on their age and who is doing the recommending. This is so deeply ingrained in medical practice and public health ideology that most women do it, and feel virtuous about it.

The problem is that a very respectable case can be made that there is no good evidence that it saves lives, or at best it might prevent a breast cancer death in one out of some hundreds of women who are screened. And there is a huge cost. Most positive findings on screening mammography are false positives, but you still have to go through biopsy, anxiety, etc. And, the majority of true positives are non-invasive, symptom free lesions call Ductal Carcinoma in Situ, which result in surgery, chemotherapy, pain, expense, terror and all that; but many of which would never have become invasive or caused any problem. We don't know how many, and we have no way of knowing which ones.

Now listen up! That does not mean that you should not get a mammogram. First of all, see my post linked above for a further link to a discussion of Bayes Theorem. It makes much more sense to have a mammogram if you have a family history of breast cancer, or other risk factors such as never having had children, or having used HRT for an extended time; it is imperative if you have any symptoms such as a lump in the breast or an abnormal discharge; it may well make sense if you're just the right age, say somewhere between 55 and 65; and it makes sense if you personally are more anxious about getting breast cancer than you are about the possibility of a false positive and the expense and pain and other negative consequences.

I'm not practicing medicine here, I'm just urging you to talk this over with your doctor and then make your own decision. My doctor is constantly trying to get me to take a PSA test and I am just as steadfastly refusing. He doesn't like it but that's tough, he works for me, not the other way around. There is a very powerful industry and entrenched interest behind this screening mammography thing, and it's awfully hard to fight it. But it's worth questioning.

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