Breast cancer treatment sometimes involves removing the cancerous breast. However, an increasing number of women are also having their remaining healthy breast removed to prevent cancer in it as well.

The latest figures show that preventive mastectomies are up 150 percent. A new study might help breast cancer patients with the agonizing decision of whether or not to remove their remaining breast.

Researchers studied the health records of 542 women treated for breast cancer between 2000 and 2007. Doctors identified three distinct risk factors for developing a tumor in the second breast.

• Multiple tumors in the original breast
• An original tumor that started in the milk-producing lobes and spread like seeds.
• High breast cancer risk according to age, race and family history

Some doctors said they are concerned about unnecessary mastectomies, pointing out that chemotherapy combined with  hormone therapy is a good alternative to surgery.

“Fear is definitely a big motivating factor (in getting the second breast removed),” said Dr. Sharon Rosenbaum Smith with St. Luke’s-Roosevelt Hospital in New York City. “They've been through it once. They don't want this to happen again.”

That was the case with Bridget Cochran, a breast cancer patient and mother of three.

“I'm afraid for me, but I'm more afraid for my kids, for they won't have me,” she said.

Three years after having one breast removed, she developed a tumor in the other, which led to another mastectomy.

“If I would have known then what I know now, yes, I would have gotten the second one removed at the same time,” she said.