MRIs May Drive More Women to Mastectomy

May 16, 2008— -- Women with breast cancer are increasingly opting for mastectomies over lumpectomies, a surgical procedure that removes only the cancerous tumor inside the breast, say researchers at the Mayo Clinic in Rochester, Minn.

The possibility that the growing use of magnetic resonance imaging for diagnosis is partly responsible for this increase is raising new concern over whether women are getting mastectomies needlessly. One leading breast cancer specialist called the MRI-driven boost in mastectomies "alarming."

Mayo Clinic researchers evaluated mastectomy rates at their institution between 1997 and 2006 in relation to the use of preoperative MRI -- a screening tool that is more sensitive than traditional mammography but also more likely to result in false positives for breast cancer.

Researchers sought to answer the question of whether the more sensitive MRI screening test would cause more breast cancer patients, frightened by the lumps and bumps this test picked up inside their breasts, to have the whole breast removed rather than just those lumps that were determined to be cancerous.

They found that among 5,464 women who had surgery for early-stage breast cancer, the mastectomy rates rose between 2003 and 2006, when the number of patients receiving an MRI doubled from 11 percent in 2003 to 22 percent in 2006.

The researchers reported that the number of mastectomies performed at their institution have increased by 13 percent over a period of three years. In 2003, researchers reported that mastectomy accounted for only 30 percent of early-stage breast cancer surgeries. The number rose to account for 43 percent of all breast cancer surgeries in 2006.

Moreover, researchers found that women who received an MRI to screen for breast cancer were significantly more likely to choose a mastectomy than those who did not receive an MRI. More than half of the patients who received an MRI -- 52 percent -- chose to undergo a mastectomy, compared with 38 percent of patients who did not have an MRI.

Technology Influencing Patient Decisions?

Dr. Matthew Goetz, one of the researchers involved in the study and assistant professor of oncology at the Mayo Clinic, said that although the study cannot confirm precisely why so many more women are opting for mastectomies at the Mayo Clinic, it undeniably ties the increase in mastectomy rates to the increased use of MRI.

"New imaging modalities like MRI ... have influenced [the patients'] decision to get a mastectomy," Goetz explained. "For patients who had preoperative MRIs, the mastectomy rate was significantly higher over the whole four-year period."

Many doctors worry that because the MRI test is more sensitive but less specific, it may be responsible for unnecessary surgery to have benign lumps removed and perhaps unnecessary worry.

Dr. Henry Kuerer, professor and director of the Breast Surgical Oncology Training Program at the M.D. Anderson Cancer Center in Houston, said that his own experience has not suggested an increase in mastectomy rates.

"We are not seeing an increase in our mastectomy rates but are seeing increasing women referred to us from the community who are scared to death by frightening MRI reports without appropriate biopsy," Kuerer said.

"The study is alarming, and it has always been our worst fears that breast MRI might result in increasing use of mastectomy for breast cancer," Kuerer added. "However, the key take-home message for women and their doctors is to insist that any suspicious findings on MRI be biopsied before the decision to undergo mastectomy is made."

Moreover, a study published in the January 2008 issue of the Journal of Clinical Oncology showed that use of an MRI did not improve breast cancer recurrence rates.

Traditionally, MRI was used only on women with dense breasts or those in a very high risk bracket for developing breast cancer. But today, many experts say that the use of MRI is on the rise, and is having an undeniably detrimental effect on patient outcomes without having any benefit for disease outcomes.

"I am very concerned about this," said Dr. Michael Sabel, associate professor of surgery in the Division of Surgical Oncology at the University of Michigan. "Here you have doctors ordering MRI on every breast cancer patient, leading to more mastectomies and not decreasing the local recurrences seen in the women having lumpectomy. That means MRI is detrimental."

"As it is being used right now, it is hurting more women than it is helping," Sabel said.

Mastectomy a Growing Choice

Such a trend first entered into the public eye when former first lady Nancy Reagan opted for a full mastectomy over a lumpectomy in 1987 -- a time when nearly every woman with breast cancer wanted nothing more than to conserve her breasts.

Today, more and more women seem to opt for mastectomy over breast conservation. Goetz said he believes one reason for this might be the plethora of new breast reconstruction options that women have available after losing one or both of their breasts with this surgery.

And although there is currently no data to support the idea that this trend in increased mastectomy rates is occurring nationwide, many experts said they have witnessed the increase in their own practice.

"I have definitely seen that trend in my practice," said Dr. Christina Finlayson, director of the Dianne O'Connor Thompson Breast Center at the University of Colorado Hospital.

According to Finlayson, her own experience has lead her to believe that part of the reason for the increase in mastectomy rates is because of the increased use of MRI, but patient preference also accounts for a large part of it.

"I think that 20 years or so ago, when women were given the option of breast conservation, there was a huge interest in not 'having to have a mastectomy,'" Finlayson explained. "Now I think the pendulum is shifting toward -- 'I don't ever want to have to think about this again,' and 'I want to do everything possible'."

Because mastectomy, and particularly bilateral mastectomy -- the removal of both breasts rather than one -- obviates the need for future mammography and biopsies, many more women seem to be choosing mastectomy out of the belief that it will allow them never to have to worry about another breast cancer scare again.

"The problem, however, is that the data doesn't support any improved outcomes with mastectomy over breast conservation," Finlayson said. "It is very hard, however, to alter emotion with data."