Anyway, about once a week, a woman asks if she reaaaallllly needs a mammo every year. Until about 2009, there was an official answer for this question, which was “it’s a good idea, yeah.”
But then there was this report (a U.S. Preventive Services Task Force report, to be exact), a huge study of studies that concluded an annual screening mammogram for women ages 40-49 doesn’t do more good than harm. The task force gave a grade “C” to the recommendation for routine annual screening mammograms for women in their forties. In its own words, that’s a recommendation against the every-year mammogram as needless expense, inconvenience and worry for not much benefit.
It’s sort of shocking. The annual mammogram is carved in stone for so many women. It’s common for a woman to schedule her mammogram on her birthday as a way to remember to get those mamms grammed. Walking out of a yearly mammogram feels like getting a clean bill of health.
It’s hard to change a routine that feels safe, so it’s understandable that women and clinicians have been slow to change (although there was a measurable drop in mammography numbers last year, 2014).
The report’s complexity is another speed bump on the road to less rack-smashing. The recommendation is sort of the legal equivalent of saying someting “is not not legal.” It’s full of qualifications and “howevers,” starting with a risk assessment statement: “Applies to women 40 and over who are not at increased risk by virtue of a known genetic mutation or history of chest radiation.” Most women haven’t been tested for the mutation, so they don’t know whether or not to start or continue with annual mammograms.
And this statement, which presumes a woman knows a whole lot about her breasts, her genes and her family’s medical history: “The U.S. Preventive Services Task Force (USPSTF) makes recommendations about preventive care services for patients without recognized signs or symptoms of the target condition.” What is your action step if you don’t know whether you have recognized signs or symptoms? And what the heck is the “target condition”?
And then there is this note that screening does save lives. “The frontier curves for the mortality outcome show only small gains but larger numbers of mammograms required when screening is started at age 40 years versus age 50 years.“ Huh. So there were some small gains in extra years of life. That definitely seems worth it. And this, from a report used by the task force: “Trials of mammography screening for women aged 39 to 49 years indicate a statistically significant 15% reduction in breast cancer mortality for women randomly assigned to screening versus those assigned to controls.” Huh. 15% seems like a lot. So screening women in their forties does actually save some lives.
Also from the subsidiary report: “Our meta-analysis of mammography screening trials indicates breast cancer mortality benefit for all age groups from 39 to 69 years, with insufficient data for older women.”
So the data indicate a small but significant benefit in mammograms in your 40s. If so, why not recommend screening?
How do you interpret that? If we are saving lives, or at least adding years to a very few women’s lives, where’s the downside to that?
The report’s short answer is that the harms, considered as a whole, outweigh the benefits. Breast cancer gets all the ink, while the harms have received very little public attention.
Those funbags filling out your bra are unbelievably complex structures. There’s a lot of stuff in a breast. Some of that stuff can look like stuff that shouldn’t be there. Ten thousand screenings lead to about 500 “positive” findings because of that stuff. Several hundred of those women will get more imaging, which is more radiation, more stress, cost and inconvenience for results that are usually negative. Stress, cost and radiation have real physiological and financial consequences.
The number of true positive—actual cancers–is in the low double digits, less than 40 in 10,000. Many of theses are small, noninvasive cancers like ductal carcinoma in situ (DCIS), which can remain unchanged for years, or grow slowly but not spread. DCIS can result in more mammos and ultrasounds or MRI, needle aspirations, and biopsies. In an overabundance of caution, some doctors and patients opt for treatment. Lumpectomies carry a small risk, and radiation, chemo and hormone therapy have real, lasting physiological consequences. I know women whose treated DCIS led to cellulitis, diminishment of arm function and more.
Throw in the extra stress, anxiety, cost and just the damn inconvenience of overdiagnosis and overtreatment, and the task force concluded that an annual screening isn’t worth it for women under 50.
Plenty of organizations disagreed: The American Cancer Society, American College of Radiology, the Society of Breast Imaging and Mayo Clinic either “support” or recommend annual screening mammograms.
You might think, “I’ll just keep doing breast self-exams and if I feel something, I’ll go get a mammo.” As it turns out, breast self-exams don’t seem to improve outcomes, as shown in two large studies done outside the U.S. No ”mortality benefit” was found, and further, women who do breast self-exams undergo more additional and ineffective imaging and more biopsies than non-feelers. (The American Medical Association and the National Comprehensive Cancer network continue to recommend breast self-exams.)
Yeah, so now we’re back where we were: annual mammogram or not?
Here’s the thing: the individual stories. To say “outcomes aren’t improved” is no comfort to a woman in her 40s who discovers she has a fast-growing lump, or a family who loses a mother-wife-sister in her forties, the 2 to 6 women in 10,000 whose screening mammogram actually did turn up an invasive cancer.
So the task force adds, “The decision to start regular, biennial (every other year) 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.” In other words, if you’re more comfortable having mammograms prior to age 50, then, sure. Peace of mind is worth a lot.
If you’re still figuring it out, here are some reasons you might be more comfortable putting your knockers in the tortilla press before 50: You have a first-degree relative (male or female) with a diagnosis of breast cancer. You have a personal history of any kind of cancer. You have the genetic mutation Brca1 or Brca2. You have extremely dense breast tissue. You are post-menopausal and still have dense breast tissue.
Once you and your melons are 50, breast cancer risk starts to climb, and the advice is more straightforward, with touch of ambiguity. The report recommends a mammogram every other year for this age group. Once the data were crunched, it turns out that screening every other year provides 77% to 99% the same effectiveness as annual screening. Ninety-nine percent seems pretty decisively in favor of a mammo every two years.
But 77%? Like other parts of the report, what do you, you personally, do with that?
Me personally, I got a late start on mammograms, and forget to schedule them regularly. There’s also this awkward thing where I know most of the mammographers in town, so that’s… awkward. I’m comfortable with ambiguity and uncomfortable with overdiagnosis and overtreatment. And really uncomfortable with excess radiation. (And grizzly bears. But more so radiation.) I go every other year.
I read the reports so you don’t have to. If you want to (heaven help you) they’re here: http://annals.org/article.aspx?articleid=745237 and here http://annals.org/article.aspx?articleid=745247 and here http://www.ncbi.nlm.nih.gov/pubmed/7872591.
I’m just one mammographer who reads too much, so weigh your risks, then stir in your level of anxiety about knowing what’s going on in your lady lumps. Then talk it over with your clinician. When guidelines forget how to guide, an expert opinion can help clarify how to relate the swirling mass of data to your tatas.