Double mastectomy significantly lowers death risk for women with BRCA associated breast cancer

Harold Mandel's picture
A woman examining her breasts

Breast cancer can be deadly and a double mastectomy is considered the most extreme form or intervention to preserve life. There has been a great deal of coverage in the press of this surgical procedure for breast cancer ever since Hollywood actress Angelina Jolie had a double mastectomy last year at 37 years old after discovering she had the BRCA gene. Sympathetic support for her decision swelled, with however questions being raised as to whether or not her response to her condition was too extreme. Recent research shows the decision to have a double mastectomy for her condition was rational with increased risks for death from breast cancer associated with the BRCA gene supported by the facts.

Reseachers studied contralateral mastectomy and survival after breast cancer in carriers of BRCA1 and BRCA2 mutations, reported the British Medical Journal on Feb. 11, 2014. The objective of this research was to compare the survival rates of women who were found to have BRCA associated breast cancer who had a contralateral mastectomy versus women who did not undergo mastectomy of the contralateral breast.

The participants included 390 women with a family history of stage I or II breast cancer who were carriers of BRCA1 and BRCA2 mutations and who were initially treated with unilateral or bilateral mastectomy. 181 of these patients had mastectomy of the contralateral breast. The patients were followed for up to 20 years from the time of diagnosis.

During the follow-up period 79 women died of breast cancer, with 18 deaths in the bilateral mastectomy group and 61 in the unilateral mastectomy group. The survival rate for women who had mastectomy of the contralateral breast was 88 percent. For women who did not have mastectomy of the contralateral breast survival was 66 percent. Therefore, contralateral mastectomy was found to be associated with a 48 percent reduction in death from breast cancer.

In consideration of these results the researchers predict that out of 100 women treated with contralateral mastectomy, 87 of these women will be alive in 20 years in comparison with 66 of 100 women who are treated with unilateral mastectomy. It has been suggested by this study that women who are positive for BRCA mutations and who are treated for stage I or II breast cancer with bilateral mastectomy are not as likely to die from breast cancer as women who are treated with unilateral mastectomy. However, the researchers have cautioned further research is necessary to confirm these findings.

There is a lifetime risk of breast cancer of 60-70 percent in women who carry a germline mutation in either the BRCA1 or BRCA2 gene. Once these women are diagnosed with breast cancer they have a high risk of a second primary breast cancer. The primary goal of treating hereditary breast cancer is to lower the likelihood of patients dying from a first breast cancer. However, this is also important to lower the incidence of, and mortality from, a second primary cancer. In North America about 50 percent of women with a BRCA mutation will undergo mastectomy of the contralateral breast in order prevent a second breast cancer.


Previous studies have shown women with breast cancer and BRCA mutations who have mastectomy versus lumpectomy, and mastectomy of the contralateral breast, versus unilateral mastectomy, have large and statistically significant lower risks of ipsilateral and contralateral breast cancer, respectively. It is now known that the reduction in second primary cancers has a positive impact on breast cancer specific mortality. It was observed that the significant mortality benefit which is associated with mastectomy of the contralateral breast becomes most apparent in the second decade of follow-up after the initial diagnosis of breast cancer.

The researchers have concluded that it is reasonable to propose bilateral mastectomy as the initial treatment option for women who are suffering from early stage breast cancer who are carriers of a BRCA1 or BRCA2 mutation. In women with the BRCA1 or BRCA2 mutation who have been treated in the past with unilateral mastectomy or breast conserving surgery, a second surgery should be discussed as a possibility.

This study showing women with BRCA associated breast cancer who have a double mastectomy are nearly 50 per cent less likely to die of breast cancer within 20 years of diagnosis in comparison to women who have a single mastectomy was led by researchers at Women’s College Hospital. In further discussion of BRCA associated breast cancer by the researchers it is pointed out that a double mastectomy may in fact be an effective first line treatment for women with early stage breast cancer who carry a BRCA1 or BRCA2 genetic mutation.

The BRCA1/2 genes are in a class of genes which typically serve to protect people from acquiring cancer. However, women who inherit a mutated form of these genes have a significantly increased risk of developing breast and ovarian cancers. Kelly Metcalfe, an adjunct scientist at Women’s College Research Institute, has said, “Women with a BRCA mutation have a 60 to 70 per cent chance of developing breast cancer in their lifetime, and once diagnosed, a further 34 per cent chance of developing breast cancer in the opposite breast within 15 years.” The importance of providing genetic testing for BRCA1 and BRCA2 at the time of breast cancer diagnosis, if appropriate, is highlighted by this study. The genetic information which is offered could help women make decisions which ultimately may improve their chance of surviving breast cancer.

Last year Hollywood actress Angelina Jolie publicly announced her decision to have a double mastectomy and breast reconstruction surgery after she discovered she had the BRCA1 gene. She said her doctors estimated she had a 50 per cent risk of developing ovarian cancer and an 87 per cent risk of breast cancer due to having the BRCA1 gene. The existing research overall supports the benefit of a double mastectomy in preventing breast cancer in women who have this gene mutation. However, the study’s researchers have cautioned more research is necessary to confirm the benefit of a double mastectomy in lowering the risk of death in women who are diagnosed with BRCA associated breast cancer.

There is at times a great deal of skepticism about the value of genetic testing. However, in some instances, such as in dealing with BRCA associated breast cancer, research seems to confirm there
may very well be a great deal of value to genetic testing. I suggest that when appropriate BRCA gene testing be offered for women. If there are positive test results very careful counseling should follow with an explanation of the possible benefits for increased chances for survival with a double mastectomy.

Photo courtesy of marin/