Health
According to the report, women who had a mastectomy and kept their other breast had as good results as those who had a double mastectomy.
In the Division of Plastic Surgery at Brigham and Women’s Faulkner Hospital, Dr. Matthew Carty reviews plans for additional surgery with a patient who has undergone a double mastectomy. Pat Greenhouse/Globe Staff
For the more than 310,000 women diagnosed with breast cancer each year, no matter how successful their treatment, one fear always lingers. Could the disease reappear, even years later? What if it reappears in the other breast? Could they protect themselves today by having a double mastectomy?
A study has concluded that removing the other breast provides no survival benefit. Women who had a lumpectomy or mastectomy and kept their other breast did as well as those who had a double mastectomy, reported Dr. Steven Narod of Women’s College Hospital in Toronto and colleagues, based on U.S. data from more than 661,000 women with breast cancer on one side.
In the study, published Thursday in JAMA Oncology, the researchers added that most women did very well; the risk of cancer in the other breast was about 7 percent over 20 years.
But the study’s findings may not apply to women who carry a genetic variant, BRCA1 or BRCA2, that significantly increases their cancer risk. For the 1 in 500 American women who carry this variant, cancer researchers agree that a double mastectomy is worth considering.
Narod said the finding that double mastectomy does not protect against death in many cases of breast cancer seems counterintuitive. An accompanying editorial, written by Dr. Seema Ahsan Khan, a breast cancer surgeon at Northwestern University, and Masha Kocherginsky, a biostatistician also at Northwestern, called the finding a puzzle.
Previous smaller studies have reached the same conclusion. But, Narod says, some doctors have questioned the methods used in previous research.
According to Dr. Eric Winer, a breast cancer specialist and director of the Yale Cancer Center, this new study should reassure women. Like previous studies, “it suggests that there is absolutely no difference in survival between a lumpectomy, a mastectomy or a double mastectomy.”
According to Dr. Angela DeMichele, professor of medicine and co-director of the breast cancer program at the University of Pennsylvania, this new study “provides a rigorous analysis.”
Narod said he and his colleagues approached the risk of developing cancer in the other breast “in a very systematic way.” They reported that the 7 percent risk of developing a second cancer was consistent regardless of the stage of the initial cancer when it was detected in the first breast. The researchers calculated that 69 out of 1,000 women with cancer in one breast would develop cancer in the other breast within 20 years.
Such cancer is a worrying sign, which quadruples the risk of death.
Although women who had double mastectomies rarely had a second cancer in the small amount of remaining breast tissue, the study was large enough to include those who did, and their risk of death was also increased fourfold.
“But what’s going on?” Narod asked, noting that it would make sense that if cancer occurring in the second breast could kill, then “preventing it with a double mastectomy would save lives.” But that’s not the case.
He concluded that what killed him was the spread of the first cancer to other parts of the body.
DeMichele said she carefully explains to patients that they have a real choice in treatment; they do not have to have a double mastectomy.
Many women, she said, believe that the more surgery they have, the better their chances of recovery. That’s why they want to have both breasts removed.
She explains that removing the second healthy breast does not prevent cells from the newly diagnosed cancer from spreading to other organs and bones. “That’s why chemotherapy and hormone treatments are so important,” she tells patients. “They’re designed to kill these cells.”
The reason a second breast cancer is a bad sign, DeMichele said, is not that it is more likely to cause death, but that it means the patient has “a greater propensity to develop breast cancer, which may even have spread from the other breast.” The majority of women who never develop cancer in the second breast do not have this propensity, she added.
Winer explained that because cancers in the other breast can occur, it was important for women to be vigilant about screening. “We want to identify these cancers as early as possible,” he said.
Khan also explained that she advises women that double mastectomies are not a panacea. But, she added, some women have reasons for choosing to have them anyway.
They want to avoid the anxiety of screening and additional tests if a screening reveals a suspicious area. And they cannot face the idea of undergoing treatment again for cancer in the second breast.
Other women who have one breast removed and reconstructed choose to do the same for the second breast for aesthetic reasons.
“The decisions are complex,” she said.
“I always warn women that a second cancer could occur in the future,” she said. “But if it does happen, the chances of survival are good.”
This article originally appeared in The New York Times.
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