By Pamela Jones, M.D., M.P.H.

More women diagnosed with breast cancer in one breast are opting to remove the other breast as well, and a small new study suggests that the decision may be driven by fear rather than the actual risk of dying.

Researchers from the Boston-based Dana-Farber Cancer Institute surveyed 123 women aged 40 or younger, all of whom had cancer in one breast and chose to undergo double mastectomy. A whopping 98 percent of them said their choice to remove the healthy breast was driven by the desire to avoid a cancer recurrence.

But was it medically necessary? For women with early-stage disease and no BRCA gene mutations, the odds of developing breast cancer in the opposite breast are less than one in 100. And while no study has proven that removing a healthy breast extends life, 94 percent of the women surveyed cited "increased survival" as a main reason for their double mastectomy.

Study author Shoshana Rosenberg, a breast cancer epidemiologist at the Harvard School of Public Health, said the findings suggest that women are making "an emotional decision" when they really need information.

"The results show that anxiety, fears, and concerns about recurrence are not being adequately addressed in the decision-making process," she said. "We need a combination of more effective risk communication and also need to address concerns and anxiety early."

But breast cancer experts not involved with the study are split over the findings.

Lillie Shockney, administrative director of the Johns Hopkins Avon Foundation Breast Center and a two-time breast cancer survivor, said having a double mastectomy after being diagnosed with cancer in a single breast can offer peace of mind.

"I have patients say, 'Can you guarantee my breast cancer won't come back?'" Shockney said. "Since there are no absolutes, we have to say, 'No I can't.' Patients want to reduce their chances to the lowest probability."

On the other side of the debate is breast cancer surgeon Dr. Susan Love, who said she feels that many women opt for mastectomies with a false impression of what reconstructive surgery can offer.

"There is a fantasy that you'll have the perfect breasts you always wished you had, and you may or may not be happy with that," said Love, noting also that many women don't realize that reconstructive surgery usually leaves the breast completely numb. "For those of us who started out our careers creating randomized controlled trials to show that lumpectomy and radiation were just as good as mastectomy, it's distressing when people are doing bilateral mastectomies."

Doctor's Take

What are young women facing early-stage breast cancer to do? If this study tells us anything, it's that when it comes to choosing treatment, communication and information are key.

Women can't understand their diagnosis and risk factors for recurrence unless they talk to their doctors about it. Doctors and caregivers have to know their facts and then help guide a patient toward the decision that is best for her.

While breast cancer is a disease that will affect as many as one out of every eight women in the U.S. over their lifetime, it's a disease much more common in older women. But every woman, regardless of age, is an individual, and ultimately her treatment is a personal choice.