Should the Ovaries Be Removed in Patients With Hereditary Breast Cancer (Carrying Mutations in the BRCA1 and BRCA2 Genes)?

Although its incidence is low, "genetic predisposition" is the issue about which breast cancer patients have the most misconceptions. Almost every woman wonders after a breast cancer diagnosis whether her disease is due to a genetic predisposition.

Unless accurately informed, some patients ask their doctor during treatment planning to remove both breasts and even their ovaries. Two genes come to mind when discussing genetic predisposition to breast cancer: BRCA1 and BRCA2. These genes act to prevent tumor formation in our bodies. Structural abnormalities (mutations) in these genes increase the risk of breast and ovarian cancer in carriers to a life-affecting degree. Among all breast cancer patients, the proportion carrying these abnormal genes is approximately %5-6. A family history of breast cancer increases the likelihood of cancer associated with these genes, but without genetic testing it does not mean the cancer is hereditary. Testing only rarely identifies individuals carrying these genes. Nevertheless, identifying carriers among women diagnosed with breast cancer is extremely important, both for themselves and for the future of children to whom they may pass these genes. Studies have shown that their lifetime risk of breast cancer is around %80 and of ovarian cancer around %50.

Several questions have arisen over the years for women with breast cancer who carry this gene. First, should both breasts be removed during surgery? Second, should both ovaries be removed to reduce ovarian cancer risk? Third, does early removal of the ovaries reduce breast cancer recurrence and the risk of death?

Studies conducted to date have answered the first two questions. In patients diagnosed with breast cancer who carry the BRCA1 and BRCA2 genes, surgery on the opposite breast with the patient's consent substantially reduces breast cancer incidence (%90) and correspondingly reduces mortality risk. Similarly, subsequent removal of the ovaries reduces ovarian cancer incidence (%90) and naturally reduces mortality risk. Therefore, removal of the ovaries is recommended for a woman diagnosed with breast cancer if she is near the end of her reproductive years or has had the children she wishes to have.

A combined analysis of numerous studies conducted to date has clarified the answer to the third question. I would like to share the study's result and the lesson we can draw from it.

The study included women carrying a BRCA1 or BRCA2 mutation with early-stage (stage 1 or 2) breast cancer: of 676 women, 345 underwent oophorectomy (removal of the ovaries), while 331 did not. Patients were followed for an average of 12,5 years to assess breast cancer mortality. Women whose ovaries were removed had a %56 lower breast cancer mortality rate. When assessed according to mutation type, breast cancer mortality risk decreased significantly in BRCA1 mutation carriers, while no such effect was seen in BRCA2 mutation carriers. However, because the proportion of patients carrying the BRCA2 gene was low, interpretation regarding BRCA2 may be misleading. Ovary removal also produced a stronger effect in patients with hormone-insensitive (estrogen receptor-negative) breast cancer.

In conclusion; according to this study, removing the ovaries significantly reduces the risk of death from breast cancer in women with breast cancer carrying a BRCA1 mutation, and this effect is particularly pronounced in hormone-insensitive breast cancer. We listed the most commonly asked questions above, and in all cases, if there is no specific contraindication, removal of both breasts and ovaries at an appropriate time appears beneficial for women with hereditary breast cancer. However, many cancer centers in our country do not perform BRCA1 and BRCA2 mutation testing even in high-risk patients.

Who should receive BRCA1 and BRCA2 testing (American Cancer Institute, December 2011)

• Patients with a family history of breast cancer who were diagnosed with breast cancer before the age of fifty 
• Cancer detected in both breasts of the same patient 
• Breast or ovarian cancers detected in the same patient and/or family members
• Multiple breast cancers
• BRCA1- or BRCA2-related cancer in a family member 
• Male breast cancer cases 
• Ashkenazi Jews diagnosed with breast cancer 
• In recent years, patients with breast cancer described as "triple negative," which is hormone-insensitive and does not carry the her2 receptor, have also been recommended for BRCA1 and BRCA2 testing.