Let's see here. Insurrectionist doesn't link to the policy recommendataions, but a Google search turns up
this, which seems to match his description. The actual recommendation states,
USPSTF wrote: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 patient context into account, including the patient's values regarding specific benefits and harms.
That strikes me as a pretty reasonable take on the issue, given the state of the science.
I did a bit of googling on the topic of the value of mammograms, and found quite a lot of contradictory stuff on the internet. A lot of sites claimed mammograms caused cancer, but they tended to be sites with names like naturalnews.com that also thought vaccines caused autism and GM foods are a great source of evil, etc. Long on the "intervention and radiation are evil" aspect, short on numbers. That may pass the epistemological filter of some folks; it doesn't pass mine. On the other hand, I found a lot of very official sites that said, "Well, the American Cancer Society recommends . . . " which were also short on numbers.
The most useful article I found on the topic was
this meta-study from 2007, in the Annals of Internal Medicine. If you like numbers and care about the topic, it's worth a read. I'll bottom-line some of the findings for you:
Study wrote:The latest meta-analysis demonstrated that screening mammography every 1 to 2 years in women 40 to 49 years of age results in a 15% decrease in breast cancer mortality after 14 years of follow-up . . . It is smaller than the 22% reduction seen among women 50 years of age or older . . .
They discuss their methodology quite a bit, but these are just raw comparisons between the populations of women who do get screened and those who don't. So any effects of mammograms causing harm are factored in; the net effect on mortality due to breast cancer is an improvement, and a fairly sizeable one.
Moreover, it isn't a randomized study. They note that women who are higher risk are more likely to go for the screening. They don't try to account for the effect--just note it as a limitation of the study--but this would make screenings appear less effective at saving lives than they actually are.
The effect tunnelcat talked about -- radiation during screening -- is also addressed.
Study wrote:No studies directly measure the risk for cancer caused by radiation exposure from mammography screening. Any effect of screening radiation on breast cancer incidence is small and is difficult to separate from the effect of screening on breast cancer detection. Estimates of the risk for radiation from mammography are derived from cohort studies of other forms of radiation exposure, including high-dose exposures (over a short or prolonged period of time) and low-dose exposures from other sources (44–68 ). In general, studies of low-dose exposures have been inconclusive, with some demonstrating a small increase in risk and others finding no association (44, 47, 54, 57). However, studies of high-dose exposures have found that women who were exposed to high levels of radiation have a statistically significantly increased risk for breast cancer, with relative risks ranging from 1.33 to 11.39 for exposures of 0.3 to 43.4 Gy (46, 52, 55, 59, 65, 67, 68 ). High-dose exposures that have been studied include radiation treatment, diagnostic radiography, and atomic bombs. The increase in risk seems to be larger with higher doses of exposure, younger age at exposure, and longer follow-up.
The mean glandular dose from 2-view mammography is approximately 4 to 5 mGy. A recent analysis of radiation dose in the United Kingdom trial of mammography screening in women 40 to 48 years of age found a mean glandular dose of 2.5 mGy for an oblique film and 2.0 mGy for a craniocaudal film (69). However, dosage varies among facilities and increases with breast density. If women 40 to 49 years of age are screened every year and an estimated 20% experience a false-positive test result requiring additional radiographies, the average cumulative exposure from screening during the decade will be around 60 mGy.
The upshot of this is, the radiation received from a mammogram is really not very much. They estimate 60 mGy over a decade; the lowest measurable increase in risk they can find is for .3
Gy -- 5 times as much. So while radiation does cause cancer, there isn't conclusive evidence that the
amount involved even in a decade worth of mammography is enough to cause cancer
at all. And even if it does, how
much it causes would be factored into the general studies on breast cancer mortality rates: given that women who are screened have lower mortality rates, the mammograms must be usefully finding significantly more cancers than they cause.
Sort of like wearing your seatbelt, I suppose. For every accident where it hurts you, there are a hundred (or a thousand or whatever it is) where it saves your life. The radiation does in a single mammogram is tiny. And even if the radiation involved in several decades of screenings might be enough to start pushing up against the statistical margins, the cost is outweighed by the benefits. You're much more likely to find and prevent cancer than you are to cause it.
The cost vs. benefit debate comes up for women in their 40s given that individual risk factors affect how useful mammograms are. Basically, if you don't have significant risk factors, they're a lot less likely to find something before you turn 50:
Study wrote:Women with a history of breast cancer in a first-degree relative are more likely to have screen-detected cancer than are women without a family history of breast cancer (139–141). For women 40 to 49 years of age, 4.7 cases are detected per 1000 examinations among women with a family history compared with 2.7 cases per 1000 examinations among women without a family history. For women 50 to 59 years of age, the rates are 6.6 and 4.6 cases per 1000 examinations, respectively (140, 141). In general, the rate of cancer detection among women with a family history of breast cancer matches that among women without a family history who are a decade older. The incidence of false-positive and false-negative mammograms seems to be slightly higher among women with a family history of breast cancer than among women without a family history of breast cancer (139–141).
It depends on the person. Is the discomfort, cost, and risk of a false positive (carrying with it biopsies and worry and so forth) worth a 0.27% chance they'll find something? Does that change if it's 0.47%? 0.66%? That's a pretty personal question, but given that there's a statistical falloff in effectiveness of mammography for healthy women in their 40s, they conclude:
Study wrote:Current evidence indicates that women 40 to 49 years of age who undergo routine mammography screening will decrease their risk for death due to breast cancer but will increase their risks for undergoing unnecessary procedures, breast cancer–related anxiety, discomfort at the time of screening, and exposure to low-dose radiation. Because the incidence of breast cancer and the effectiveness of mammography are lower among women in their 40s than among women 50 years of age or older, mammography screening results in less absolute benefit and greater absolute risk for women 40 to 49 years of age than for women 50 years of age or older. The proportion of women 50 years of age or older whose risks for mammography outweigh the benefits is widely accepted to be clinically insignificant. However, the evidence suggests that this proportion is higher and may be clinically significant for women 40 to 49 years of age. Given this difference, a woman 40 to 49 years of age who had a lower-than-average risk for breast cancer and higher-than-average concerns about false-positive results might reasonably delay screening. Measuring risks and benefits accurately enough to identify these women remains a challenge.
Given that, the USPTF recommendation of . . .
USPSTF wrote: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 patient context into account, including the patient's values regarding specific benefits and harms.
. . . seems completely sensible to me.
I can't imagine how that could be perceived as rationing. It's a recommendation, and it even specifically leaves open the option of screenings for those in their 40s who want them. It just recommends against employing them for everyone.
I can only imagine that what set off the original post was something along
these lines:
Washington Times wrote:
Leaders of the Republican National Committee say revised recommendations issued by a government-funded panel that say women only need to be screened for breast cancer after the age of 50 could be the beginning of health care rationing by the government.
RNC Chairman Michael Steele and co-chair Jan Larimer wrote a letter to President Obama Thursday, obtained by the Washington Times, that calls the new recommendations a "thinly veiled attempt to save money by limiting mammograms has the effect of placing a dollar value on a human life."
The U.S. Preventative Services Task Force, an independent panel of doctors and scientists that makes health recommendations to the government, issued these guidelines. USPSTF’s decisions are neither binding nor final, but RNC officials say it shows how the government could ration care. “Tomorrow it will be prostate exams,” they warned.
. . .
The full text of the letter is below:
Mr. President:
"We are writing to you today to express our outrage at the insensitivity towards women your White House has shown on the issue of health care. Your Administration's attempt to ration and limit access to potentially life-saving mammograms is profoundly dangerous. This thinly veiled attempt to save money by limiting mammograms has the effect of placing a dollar value on a human life.
Even worse, decisions like this are at the heart of the concern Americans have with a government run healthcare system because they cause the most harm to the least fortunate. Women rely on programs like Medicaid for access to annual mammograms. Limiting access to annual tests unnecessarily jeopardizes the health of women and places an unfair burden on those living near or below the poverty level.
This government panel claims to be concerned with the anxiety caused by mammograms resulting in false positives. That anxiety, however, pales in comparison to the threat posed by an unknown positive. It is clear that this decision is just the first step toward total government rationing of health care. Today it is mammograms. Tomorrow it will be prostate exams. In the future it will be complete government control of the tests we receive, the doctors we see and the care the government decides that we deserve.
. . .
That strikes me as being so blown out of proportion that it falls somewhere between true stupidity and cynical dishonesty. Downright embarrassing.
I'm growing more and more convinced that being out of power actively causes people to go crazy.
- Drak
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P.S., I noticed as I posted this that the USPSTF page has a pretty good study attached to it, too, justifying the recommendations. You can find the links at the bottom of the page. The numbers are in the ballpark of the study I was reading, though they measure something slightly different:
Government Study wrote:Screening biennially from ages 50 to 69 years achieved a median 16.5% (range, 15% to 23%) reduction in breast cancer deaths versus no screening. Initiating biennial screening at age 40 years (vs. 50 years) reduced mortality by an additional 3% (range, 1% to 6%), consumed more resources, and yielded more false-positive results.
