It’s potentially the biggest health headline of the week: a new study shows that more women who have developed cancer in one breast are opting for a preventive double mastectomy—even if they’re not at a higher risk for getting the disease in the second breast, and even if that means going against their doctor’s advice.
Much of the coverage of the study, published Wednesday in JAMA Surgery, took on a baffled tone, quoting medical professionals who couldn’t imagine a reason beyond anxiety to explain why patients would request an invasive procedure they didn’t technically need—and one that carries medical risks of its own. But even if this decision doesn’t make a lot of medical sense, decades of behavioral science research can offer clues as to why so many women are making it.
One big culprit here is something psychologists call the availability heuristic, said Harvard Business School behavioral scientist Francesca Gino. The easier it is for us to conjure up an event in our mind, the higher we’ll rank its probability—often leading to bad decisions and incorrect assessments of risk. A classic example is our inflated fear of plane crashes versus car crashes. Plane crashes are much less likely, yet they’re more spectacularly horrible, receiving widespread media coverage and resulting in multiple fatalities. So our minds hang on to the more vivid airplane-disaster scenario, which means we exaggerate its likelihood. In practice, that means some people are driving rather than flying – putting themselves at greater risk.
The same logic holds for cancer. “[C]elebrities developing cancer—made vivid by repeated media exposure—may increase cancer-risk perception and worry,” Gino said. She’s talking about the “Angelina effect”—Angelina Jolie, of course, famously wrote about her decision to have a double mastectomy in a New York Times opinion piece published a year ago this month, greatly boosting the procedure’s visibility. But the actress’s situation was different from what’s described in the new research; Jolie has a genetic mutation that makes it much more likely that she will develop breast cancer. More recently, Good Morning America’s Amy Robach had a double mastectomy after an on-air mammogram revealed that she had breast cancer, though she hasn’t explicitly said whether she has the BRCA genetic mutation. All of this coverage could help explain the study's finding that women who do not have that genetic mutation are still electing to have preventive mastectomies. Moreover, as Gino explained, “having experienced cancer in one breast can make women perceive they are at a higher risk of cancer in the other as well” — even if they aren't.
The availability heuristic ties into our deep, intuitive fear of loss, or what psychologists call loss aversion. The Nobel-prize winning psychologist Daniel Kahneman once wrote that “For most people, the fear of losing $100 is more intense than the hope of gaining $150.” Decades of research now confirm that, for most people in most situations, “losses loom larger than gains,” as he wrote. We easily fixate on the idea of losing something, and it can skew our decision-making.
This may especially apply to cancer patients, said Duke University behavioral scientist Peter Ubel. His research has pointed to a “cancer exceptionalism,” as he puts it—a tendency for people to make medical decisions in a different manner when cancer is involved. “That ‘C’ word has a special power,” Ubel said.
In one study he conducted, “I asked people to imagine they had a virus inside their body, some kind of infection,” he said. “And if it was left in there, it would get bigger and bigger and kill them—but, there was only a 5 percent chance it would ever do that. If you get rid of the infection you’d be cured, but there’s a 10 percent chance the procedure would kill you.” In other words, choosing the invasive surgery would double your risk of dying, compared to just leaving the thing along. Most people, Ubel says, correctly opted against the (hypothetical) surgery. But when the “virus” or “infection” was instead described as a “slow-growing cancer," more people opted for the surgery, even though doing so would double their risk of death.
Finally, there's the powerful human drive to reduce uncertainty whenever possible. “Reducing uncertainty makes us feel in control — in fact, feeling in control is associated with all sorts of good outcomes, such as increased well-being, physical health, and coping ability,” Gino said. “This strong desire to reduce uncertainty can lead to decisions that may not be good for us.” So offered the choice of either having surgery and never having to worry about breast cancer again, or not having surgery and facing creeping worry for the rest of their lives, it's little wonder many women choose the former, even when doctors recommend otherwise.
It’s hard not to emphasize with women who have had one cancer scare and want to do everything in their power to avoid a second; these biases can have a powerful pull on us, and in some cases serve useful purposes. But becoming more aware of them means women will stand a better chance of making medically sound decisions couched in an accurate understanding of the risks they face.