Regular readers of LWON know that I’m fed up with science denialism among breast cancer advocacy groups like Susan G. Komen for the Cure®.
As I write in the Washington Post today, I’m also exasperated with my doctor (one I won’t be going back to).
I’ve been reporting on breast cancer and mammography for more than 12 years now. I’ve read just about every paper that’s been published on mammography during that time, and after reviewing all the evidence, I’ve decided to opt out of mammography.
Whenever I write about this subject, I get letters and comments, and so today I’m going to address some of these objections here at LWON.
You say that the benefits of mammography have been overstated, but I’m a breast cancer survivor and a mammogram saved my life. If I’d skipped that mammogram, I’d be dead.
It’s possible that your mammogram saved your life. But it’s statistically much more likely that you are celebrating survival of a cancer that was never destined to kill you. In that case, the unpleasant treatments you received to save your life were unnecessary. Careful studies over the past decade have shown that mammography is very good at catching indolent cancers, but not very effective at finding the most deadly cancers before they become dangerous.
According to a study published in the Archives of Internal Medicine, the probability that a woman with screen-detected breast cancer avoids a breast cancer death because of mammography is less than 25%, and probably closer to 13%.
Breast cancer mortality has dropped over the last 30 years, but as physician H. Gilbert Welch explains in this New York Times op-ed, it’s not the screening, it’s improvements in treatment that have caused breast cancer deaths to fall.
I’m in my late 30’s, and I just got a baseline mammogram so that my doctor will have something to compare future mammograms to. Isn’t that a good idea — so that if I find a lump later, the radiologist will have something to compare my diagnostic mammogram to?
Nope. According to the National Cancer Institute, “Studies to date have not shown a benefit from regular screening mammography in women under age 40 or from baseline screening mammograms (mammograms used for comparison) taken before age 40.”
Wait — If scientists say baseline mammograms aren’t helpful, why do 34 states mandate that insurance companies pay for them?
Ha ha. You must be Scandinavian. Here in America, we do not practice evidence-based government. Heard of the sequester?
The baseline mammogram mandate is what happens when you let politics govern scientific policy. And we do that a lot over here.
So I should just do monthly breast self-exams then?
No. Two large studies, in China and Russia, found that BSEs did not reduce cancer deaths, but they did increase rates of biopsies.
If I read another women’s magazine article promising that self-exams work, if only you do them right, my head is going to explode. In the China study, women were given intensive instruction on how to the exams. They weren’t doing them wrong. The exams simply don’t help, and if you go back and think about Barnett Kramer’s turtles, birds and bears, it makes sense — it’s not the size or the palpability that determines whether a cancer is curable, it’s tumor biology.
No one is saying stop touching your breasts. But hyper-vigilance is unnecessary. Our bodies are not our enemies.
Are you telling me not to have a mammogram?
No. I’ve decided not to, but you should make your own decision. Screening mammograms do save lives. They’re like a lottery, where your chance of winning is very small. But if it’s your life, you’re glad you played.
As I wrote in Slate last year, “The decision about whether to get mammograms comes down to this: How much harm are you willing to risk in return for a very small chance that you might achieve a very large benefit—that benefit being your life, saved?”
Here’s how the numbers stack up, “Having an annual mammogram during your 50s reduces your risk of dying from breast cancer by less than two-tenths of a percent, increases your risk of being treated for a cancer that would not have harmed you by as much as one percent, and ups your risk of a false alarm by as much as 50 percent.”
If I don’t do mammograms or BSEs, how am I going to find a cancer if I have one?
Through a symptom. You find a lump in the shower. You notice a strange discharge from your nipple. Or, if it’s inflammatory breast cancer, the skin on your breast starts to look red or weird and feels warm.
And men — if you’re still reading — please note that you can get breast cancer too.
Why should I trust you?
Fine. Don’t. Go do your own research. Here are some good places to start.
Begin with this infographic (thanks Ed Yong)
The U.S. Preventative Services Task Force breast screening guidelines
The National Cancer Institute’s breast cancer screening PDQ
Pink Ribbon Blues: How Breast Cancer Culture Undermines Women’s Health by Gayle Suilk
Should I Be Tested for Cancer?: Maybe Not and Here’s Why by H. Gilbert Welch
The Cancer Chronicles: Unlocking Medicine’s Deepest Mystery by George Johnson
Photo by Shutterstock.
Completely agree with this. And my only gripe with a very fine FAQ is that the stats bit at the bottom is a bit confusing, not least because it’s not immediately clear whether we’re dealing with relative percentages or absolute percentage points.
I like the way the info is presented in this infographic (disclosure: my ex-exployers) http://www.cancerresearchuk.org/cancer-info/spotcancerearly/screening/breastcancerscreening/breast-cancer-screening-infographic/
Terrific infographic. Thanks for sharing that Ed.
Thank you for this.
I, too, have decided not to have any further mammograms (unless I find a lump or something).
But I will forward this link to some friends who are wavering.
While fundamentally in agreement, I think it is worth mentioning that this math applies to women at average risk. Screening is more valuable for high risk women and they should have a personalized risk estimate discussion with their doctor or a genetic counselor. I would add that to your excellent FAQ splainer.
I really appreciate this and your Washington Post piece, thank you. You don’t mention increased exposure to radiation as a risk of mammography and I wonder if that was a factor in your decision.