(NewsNation) — Getting a double mastectomy did not increase the likelihood a woman with cancer in one breast would survive compared to those who got a lumpectomy or a mastectomy, a study published last Thursday in JAMA Oncology found.
Undergoing a double mastectomy did, however, prevent cancer from appearing in the unaffected breast, according to researchers in Canada.
To obtain this result, 661,270 women, each divided into three groups of equal size, were observed for 20 years.
Over a span of two decades, 8.5% of women with lumpectomies, 9% who got mastectomies, and 8.5% with double mastectomies died from breast cancer, the study showed. In total, 3,077 deaths were reported.
“That seems like a paradox,” Dr. Steven Narod, a breast cancer researcher at Women’s College Hospital in Toronto and the lead author of the study, said in STAT. “If you get a contralateral breast cancer, your risk of dying goes up. But preventing it doesn’t improve your survival.”
Narod told STAT that while the study raises key scientific questions about contralateral breast cancers, as well as how breast cancer metastasizes and kills, it should not change the “decision calculus” around receiving a double mastectomy.
Some undergo double mastectomies for anxiety relief, or to reduce the “inconvenience” of breast cancer surveillance, STAT wrote. Laura Esserman, a breast surgeon and cancer researcher at the University of California, said to the publication that these are still sensible reasons as long as people know the procedure won’t necessarily change their chances of survival.
“I’m a big fan of giving people counseling upfront before surgery,” she said in STAT. “I try to give people time to think about it.”
One limitation of the study was that researchers did not have the subjects’ family history of the BRCA1 or BRCA2 variation status of the disease. Experts do recommend a double mastectomy if one has these variations.
