- Question from Marilyn: Is there specific data re: bilateral mastectomy with regard to BRCA patients versus just lumpectomy? If so, what is the difference in having this treatment with first breast cancer diagnosis? Are the chances of metastasis different in BRCA patients with and without bilateral mastectomy?
Beth Baughman DuPree, M.D., F.A.C.S.
Patients who carry the BRCA1 and 2 mutations are at a significant risk for cancers in the opposite breast after the diagnosis of a first malignancy. That risk is far greater than the general population, and the risk of a woman who carries the BRCA1 or 2 mutation of developing a first cancer is approximately 50% by the age of 50 and 87% by the age of 70. The choice of lumpectomy or mastectomy does not play into the risk of systemic recurrence, as tumor size, estrogen, progesterone, and HER2 status as well as axillary lymph node status will dictate the patient's risk of the cancer showing up some place else in the body.
No woman has ever died of breast cancer in her breast, as breast cancer is only lethal when it spreads to distant areas in the body. One of the reasons why women who carry the BRCA1 and 2 mutation choose bilateral mastectomy prophylactically, meaning before a cancer occurs, is that this population of women with increased risk have what is commonly known as a triple-negative breast cancer. These cancers tend to grow very fast and at this point in time, we do not have a specific targeted therapy that can be given to definitely halt any potential tumor cells from continuing to divide. Women who carry the BRCA1 mutation have approximately 56% of those cancers that are considered triple-negative. The choice of lumpectomy and radiation therapy in BRCA patients is a personal decision that a patient will make, and the risk to the opposite breast for developing a primary cancer in that breast is elevated due to the genetic mutation.
Andrew D. Seidman, M.D.
The only thing I will add, which I think the questioner was trying to address, was whether having a specific BRCA mutation implied a greater risk of systemic disease. I think it's just important that a woman understand, as Dr. DuPree noted, that a patient's BRCA status itself is not a prognostic factor for the likelihood of developing distant metastases. The determinants of that event are, again, tumor size, receptor status, nodal status, and perhaps multi-gene tests such as Oncotype DX and MammaPrint.
Editor's note: Since this research was published, new genomic tests have come to market. For the most up-to-date information, visit the Breastcancer.org Breast Cancer Tests page.
The Ask-the-Expert Online Conference called Updates From the 2010 ASCO Annual Meeting featured Andrew Seidman, M.D. and Beth Baughman DuPree, M.D., F.A.C.S. answering your questions about the latest updates on breast cancer risk, screening techniques, treatment options, and more.
Editor's Note: This conference took place in June 2010.
The materials presented in these conferences do not necessarily reflect the views of Breastcancer.org. A qualified healthcare professional should be consulted before using any therapeutic product or regimen discussed. All readers should verify all information and data before employing any therapies described here.
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