BUFFALO – The number of women going for surgery to remove the healthy breast after cancer diagnosis in one breast, according to a new study of New York State data.

And this was despite a lack of evidence that the surgery can improve survival.

The study also found that despite extensive press coverage of women who choose to have both breasts removed because of a strong family history of cancer, the rate of this surgery is relatively low and has changed little in the last decade.

Prophylactic mastectomy, the removal of a non-cancerous breast, is one method for reducing a woman’s risk of developing breast cancer.

But not much is known about the prevalence of prophylactic mastectomies for preventing breast cancer among high-risk women or on the prevalence of the surgery to prevent tumours in the healthy breast among women whose cancer is limited to one breast.

Led by Dr. Stephen B. Edge, at the Roswell Park Cancer Institute in Buffalo, the researchers examined the frequency of prophylactic mastectomies in New York State between 1995 and 2005 using mandated state-wide hospital discharge data combined with data from the state cancer registry.

They identified 6,275 female New York residents who underwent prophylactic mastectomies.

It was found that 81 percent of the women had been diagnosed with cancer in one breast, while 19 percent had no personal history of breast cancer.

The researchers found that the number of prophylactic mastectomies increased during the time period, particularly among women with cancer in one breast.

Over the 11-year study period, the prevalence of these contralateral mastectomies more than doubled.

The prevalence of bilateral prophylactic mastectomies among women with no personal history of breast cancer increased only slightly.

“These data from New York are the only data on a large population of women that examine the use of bilateral prophylactic mastectomy,” said Edge.

“These data demonstrate that prophylactic mastectomy is an uncommon procedure that is performed most commonly on women with a personal history of breast cancer. Although the total number of prophylactic mastectomies performed per year was small, it appears that the use of the surgery is increasing,” he added.

He also advised that women with breast cancer should have careful counselling regarding benefits and risks before proceeding with prophylactic mastectomy of the other breast.

The study has been published in the journal Cancer.