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Filter Applied » 2009 November

One Person Saved, Almost 2000 Screened- Worth It?

As I’m sure many of you are aware, the US Preventive Services Task Force issued new recommendations yesterday regarding regular mammograms for breast cancer screenings. Among their recommendations are the following:

The USPSTF recommends against routine screening mammography in women aged 40 to 49 years. The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take into account patient context, including the patient’s values regarding specific benefits and harms.
The USPSTF recommends biennial screening mammography for women between the ages of 50 and 74 years. (Grade B recommendation)
The USPSTF recommends against clinicians teaching women how to perform breast self-examination. (Grade D recommendation)

For women like myself who were brought up to think that early detection saves lives, these guidelines are hard to accept. At first I was comforted by reading that they don’t apply to women in high-risk groups. Then I learned that the high-risk group only included women “at increased risk for breast cancer by virtue of a known underlying genetic mutation or a history of chest radiation.” Again, having been taught early on that a strong family history of breast cancer (even without the known genetic mutation) puts one in a higher-risk category, I was shocked to learn that even these people might be counseled to follow the new recommendations. So then I took a closer look at their reasoning.

Turns out the guidelines are based on the idea that routine mammograms for women in their forties (and yearly versus biennial mammograms for women in their fifties) can actually do more harm than good. In their words, “the USPSTF reasoned that the additional benefit gained by starting screening at age 40 years rather than at age 50 years is small, and that moderate harms from screening remain at any age.” So we’re looking at “small” vs. “moderate” here. These “moderate harms” include “psychological harms, unnecessary imaging tests and biopsies in women without cancer, and inconvenience due to false-positive screening results.” They also determined that the number of lives saved by early screening is not enough to counterbalance these harmful effects. For women in their forties, one life is saved for 1904 women screened; for women in their fifties, one life is saved for 1339 women screened. This boils down to a 15% and 14% risk reduction, respectively.

Ok- I am by no means an expert, but I can tell you that I would much rather undergo the “inconvenience of a false-positive,” or what turns out to be an unnecessary biopsy, rather than die of a tumor that could have been detected, had I only found the lump via a self exam or went in for a mammogram at age 48.  I realize that the financial costs (in addition to the psychological costs) of unnecessary imaging tests and biopsies are high, and that one life saved for every 1904 women screened is a very small number.  But, when that one life saved turns to be your mother, or your wife, or your best friend- or YOU- it seems a lot bigger, doesn’t it?

My Brain, My Friend

For the past two weeks I have been vexed by an ad on the 151 CTA bus I take to work everyday. It features puzzle- a pie with eight pieces, each of which contain a number. Two of these numbers are missing, and it’s the viewer’s job to figure out what they’re supposed to be.

The reason this ad bothered me so much is because the answer was not written upside down on the bottom of the poster, as one might hope. Instead, you have to go to Marbles the Brain Store and ask an associate (which makes sense, from a marketing perspective). So, this past Friday night, I was very excited to happen upon a Marbles in the new wing of Old Orchard Mall in Skokie.

The bad news: I was not at all correct. The good news? (Read more…)

Snap, Crackle, Pop: Kellogg’s Withdraws Cereal Immunity Claim

Responding to a firestorm of criticism, Kellogg’s claim that eating Cocoa Rice Krispies will “support” your immune system has been withdrawn.  In a press release posted yesterday, the company announced it would, “…discontinue the immunity statements on Kellogg’s Rice Krispies cereals.”

Oddly, Kellogg’s maintains that, “…science shows that these antioxidants help support the immune system.” I sent them a note last week, requesting literature citations supporting this position. No reponse yet.

Nurition and health expert Marion Nestle has been blogging about the Krispie fiasco, and even has a letter from the San Francisco City Attorney, demanding evidence for the immunity claim.

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