A new study shows that great numbers of men with breast cancer are opting to get mastectomies on both breasts and even on the healthy breast as a preventive means of protection.

The study has found that between the years 2004 and 2011, the rates of contralateral prophylactic mastectomies in men nearly doubled. Around 5.6 percent of men with breast cancer have undergone the operation in the year 2011, compared with only 3 percent in 2004.

The study also shows that contralateral prophylactic mastectomy is used at increased rate as an operation to remove a healthy, unaffected breast after a diagnosis of invasive cancer in the other breast. However, the researchers cautioned that this type of mastectomy isn't always necessary. The study was published in the journal JAMA Surgery on Sept 2.

According to Dr. Ahmedin Jemal, the lead researcher on the study and vice president of surveillance and health services research at the American Cancer Society, the surgery is recommended only for a small percent of men. Moreover, Jemal told Live Science that evidence is missing to suggest that such mastectomies can help patients with cancer to live longer.

The researchers analyzed data from the North American Association of Central Cancer Registries for their study. They looked data from 6,332 men with breast cancer in one breast. All of the participants in the study underwent surgery between the years 2004 and 2011.

The findings of the research team suggest that over the study period, the men who opted to remove both breasts were, in general, younger than those who didn't. A total of 1,254 men underwent breast-conserving surgery, 278 men underwent contralateral prophylactic mastectomy and 4,800 men underwent a single-breast mastectomy. The researchers said that the rates of mastectomies decreased with the men's age.

This pattern of increasing in rates of mastectomies has already been observed in women, according to Jamel. Researchers attribute this increase in rates of this type of surgery in both genders to more frequent genetic testing and the use of MRI during diagnosis. The cause of the increase in men is not clear, but researchers believe that it can have the same reasons to those in women.

For men and women with BRCA mutations, the contralateral prophylactic mastectomy procedure is recommended, Jamel said. However, he noted that just a small proportion of people diagnosed with breast cancer have these mutations. Jemal recommended that men diagnosed with breast cancer in one breast consult their doctors about the necessity, the benefits and risks of this type of mastectomy.

According to the American Cancer Society, in women breast cancer is about 100 times more common than in men. For men with breast cancer, mastectomies are the most common type of surgeries, according to the Susan G. Komen Foundation