More Women Are Choosing Mastectomies at Mayo Clinic
This color-enhanced slide shows a magnetic resonance image (MRI) of a breast.
More women have been having mastectomies to treat early stage breast cancer at the Mayo Clinic since 2004 than during the previous 6 years, according to an analysis of surgeries done at the clinic between 1997 and 2006. While the reasons for the apparent shift are not known, the rise in mastectomy rates marks a reversal—radical surgery to remove the breast had been in decline in the United States, and at the clinic.
The findings, published online July 27 in the Journal of Clinical Oncology, appear at a time when many in the field are wondering about the role of mastectomy in this disease.
"We're seeing a change in how medicine is practiced, at least at the Mayo Clinic," said Dr. Matthew P. Goetz, a medical oncologist and leader of the study. "As a cancer community, we need to understand why that is happening. And then we need to step back and ask ourselves if this is really a good thing for patients."
One of the changes that occurred in the management of breast cancer during the study period was the introduction of magnetic resonance imaging (MRI). The investigators looked for evidence of a possible link and found that use of MRI was associated with mastectomy, though they could not show cause and effect.
Choosing Mastectomy, But Why?
The vast majority of Asian American women—in particular Vietnamese, Filipinas, and Chinese—who are diagnosed with breast cancer have mastectomies rather than breast-conserving therapy, and researchers in California are asking why. Through surveys of physicians and interviews with patients in the San Francisco Bay Area, the researchers have found that while clinical factors help determine a patient's treatment, cultural beliefs and norms also play a role.
For instance, a belief among some Asian American women that it is not important to preserve the breast after a diagnosis of cancer may have contributed to the pattern of treatment in this population, the researchers reported July 17 in BMC Public Health. In addition, some patients, particularly recent immigrants, may be hesitant to question the recommendation of a physician because to do so would be considered inappropriate.
The NCI-supported pilot study, led by Dr. Scarlett Gomez of the Northern California Cancer Center, aims to better understand the complex decision-making processes behind the high mastectomy rates. The findings could aid physicians in their interactions with patients who share these cultural beliefs, helping them deliver the most appropriate care.
"There is evidence from a number of institutions that MRI may change the management of breast cancer, and we're trying to ask whether using MRI will improve the survival of patients in the long term," said Dr. Goetz. "Right now we just don't have that data."
In the study, women who had a breast MRI were 10 to 15 percent more likely to have a mastectomy than other women. But the biggest increase in mastectomy rate occurred among women who did not have a breast MRI. This suggests that if MRI does play a role, it is certainly not the only factor, the researchers said.
"We cannot say from our study that getting an MRI led women to choose a mastectomy," Dr. Goetz said. "It's really unclear which factors are influencing women in their decisions."
Less-invasive procedures for treating early stage breast cancer came into favor in the early 1990s, when NIH recommended breast-conserving therapy—surgery to remove a tumor followed by radiation—for most women with the disease. The guidelines cited evidence that mastectomy and breast-conserving therapy were similar in terms of survival.
As doctors communicated this message to their patients, mastectomy rates declined throughout the United States during the 1990s. At the Mayo Clinic, rates fell steadily from 45 percent in 1997 to 31 percent in 2003. But between 2004 and 2006, mastectomies increased from 37 percent to 43 percent.
"We have all had the feeling that there are more women with early stage breast cancer having mastectomies, and the Mayo Clinic investigators have documented this in a nice way," said Dr. Monica Morrow, chief of the Breast Service at Memorial Sloan-Kettering Cancer Center.
In an accompanying editorial, she and Dr. Jay R. Harris of the Dana-Farber Cancer Institute stressed the need for more research on how to effectively communicate complex treatment choices to women facing the stress of a new cancer diagnosis.
"We know very clearly from the literature that breast-conserving therapy and mastectomy do not vary in terms of survival," said Dr. Morrow. "So it's a little concerning that more and more women seem to be opting for the more aggressive surgery."
She noted that further evidence of a possible shift in patient views of mastectomy includes a recent study showing increases in double mastectomies as a preventive measure among women diagnosed with cancer in only one breast.
"That report is another piece of evidence that points to a possible pendulum swing in public opinion about how aggressive patients with breast cancer want to be in preventing a recurrence or a contralateral breast cancer," said Dr. Amy Degnim, a breast surgical oncologist at the Mayo Clinic and coauthor of the current Mayo Clinic study.
She believes there may be multiple reasons for this recent change besides the increasing use of MRI. Women, for example, may be better informed about their treatment choices and side effects; attitudes about the risks of radiation treatment may be changing; and there is a greater awareness of breast reconstruction. Shifting attitudes among some physicians is another possibility.
At this point, Dr. Degnim added, it is difficult to know whether the apparent increase in mastectomies is a positive or negative development simply because too little is known about what the patients themselves think.
"Ultimately, if patients who choose mastectomy have equivalent survival and are happy with their treatment choice, then this change is not necessarily bad," she said.
—Edward R. Winstead