“I want to encourage every woman, especially if you have a family history of breast and ovarian cancer, to seek out the information and medical experts who can help you through this aspect of your life, and to make your own informed choices.”
—Angelina Jolie, “My Medical Choices,” The New York Times
A beautiful actress with a famously bountiful chest pens an op-ed in the New York Times to explain that she had her breasts removed to stave off cancer. Writing about her double mastectomy, Angelina Jolie cites patient empowerment as the reason women should see their doctors and, perhaps, get gene tested for breast and ovarian cancers.
There’s no debating the importance of taking responsibility for your own health. However, the idea that every woman should follow Jolie’s lead and seek screening is simply science-ish—another case of celebrity-based medicine gone awry.
Sonia Nanda is a genetic counsellor at Women’s College Hospital in Toronto who spent today fielding emails from worried patients. “People saying, ‘I want the test, where can I get the test, what are the guidelines?'” she explained. Such a spike in public interest would be no different than those recorded after other famous folks endorsed cancer screening. In this case, Nanda asked: “Why would you have this testing if there’s no family history?”
That’s because only a fraction of breast cancers—about five to 10 per cent—are genetic or inherited and screening is indicated for women with a family link. “That’s why everybody doesn’t need to get genetic testing,” Nanda said.
Of the minority of breast cancers caused by a gene defect, BRCA1 (Angelina’s faulty gene) and BRCA2 make up a proportion, so doctors look for these mutations. We all have BRCA genes, which are thought to work as “tumor suppressors” that stop cancerous cells from dividing. But “sometimes people are born with changes or mutations in these genes that can put them at a higher risk of cancer,” Nanda said. “A woman’s risk of developing breast cancer is low in comparison to somebody who has a mutation.” (Interestingly, BRCA mutations seem to have a higher prevalence among French-Canadian women—like Angelina’s mother—and Ashkenazi Jewish women.)
After testing positive for the mutant gene, Jolie chose to undergo a double mastectomy. It’s not necessarily the option Dr. Steven Narod, Canada Research Chair in breast cancer based in Toronto, would recommend. “It’s a drastic procedure,” he told Science-ish. “But I say the only way I can guarantee (a patient) a future without breast cancer is surgery.”
The latest systematic review on mastectomies and breast cancer prevention suggests this radical procedure can decrease the chance of developing breast cancer in high-risk women like Jolie. Still, the authors warned that even for those who have BRCA1 and BRCA2 mutations—the high-risk group—the surgery can end up being unnecessary.
“Women considering (a double mastectomy) should not only understand the risk of breast cancer,” wrote the review authors, “but also understand that many women having (a double mastectomy) would not have died from breast cancer even without having the surgery.”
So the benefits of this drastic operation may not be fully warranted—a message Dr. Gerd Gigerenzer, an expert on risk communication in health, would relay to patients. He cites this retrospective study, still the definitive work on double mastectomies in high-risk women. It looked at 639 patients with a family history of breast cancer. In the women who had the procedure, there was a reduction in the incidence of the condition and death from breast cancer: Out of every 100 women with BRCA1 who opted for the mastectomy, one died from breast cancer within 14 years. Of the 100 who did not get the surgery, five died.
“In other words,” he put it, “the mastectomy saved the lives of 4 per cent, but some 95 per cent lost their breasts without documented benefit.”
Science cannot yet predict which women will get cancer. After Jolie learned she had an 87 per cent risk of developing breast cancer—higher than the some 60 per cent average for women with her genetic defect—she made a choice.
Nanda said women like Jolie with cancer in their families should seek medical advice in order to understand their own risk, not just that of a particular celebrity.
Science-ish is a joint project of Maclean’s, the Medical Post and the McMaster Health Forum. Julia Belluz is the associate editor at the Medical Post. Got a tip? Seen something that’s Science-ish? Message her at firstname.lastname@example.org or on Twitter @juliaoftoronto